Is there a North Star for Mars?

North Star for Mars: Sunset on Mars. View full of dust. Tiny sun with dark land in foreground.
As the sun sets over the stark Martian landscape, stars come into view. Is there a North Star for Mars? Image via Spirit Mars rover, 2005/ NASA.

The 2025 EarthSky Lunar Calendar is now available! Makes a great gift. Get yours today!

North Star and South Star

We sometimes get this question. The North Star for Earth is Polaris. Does our next-door neighbor planet, Mars, have the same North Star as Earth? If not, does Mars have a star located more or less above its north pole?

Let’s talk about what we mean by North Star. Every planet in our solar system spins on its axis. Earth’s spin is what defines the length of our day of approximately 24 hours. If you continue the imaginary line of a planet’s axis out into space – in a northern direction as measured from earthly north – it might point to a star that’s visible to the eye. Or it might not. We call such stars pole stars, or North Stars. On Earth, that northern pole star – less than a degree from the north celestial pole – is the beloved star Polaris. Scouts and hikers know you can use Polaris to find the direction north when compasses fail.

Meanwhile, Earth’s Southern Hemisphere doesn’t have a comparable South Star. The nearest visible star to the south celestial pole of Earth is about 9 degrees away.

Illustration of the orbits of Earth and Mars around the sun.
Artist’s illustration of the relative tilts of the orbits of Earth and Mars, Earth doesn’t orbit exactly upright with respect to our orbit around the sun. Instead, Earth’s tilt is about 23 1/2 degrees. Meanwhile, Mars’ tilt is about 25 degrees. What’s more, the rotational axes of the Earth and Mars don’t tilt in the same direction, as in this illustration. For both reasons – different amount of tilt, and different direction of tilt – Mars doesn’t have the same North Star as Earth. Image via NASA.

A North Star for Mars?

So, does Mars have a North or South Star? The answer is … not in any satisfying way. There’s no bright North Star, and only a modestly-bright South Star, for Mars.

In the northern sky as seen from Mars, the best candidate for a North Star is located on Mars’ sky dome about 1/2 degree from Mars’ north celestial pole. That’s closer than Polaris is to Earth’s north celestial pole, but, while Polaris is relatively bright (50th brightest of all stars in the night sky), the star near Mars’ north celestial pole is faint.

In fact, this star is barely within the limit of visibility to the eye alone.

Mars’ north pole points to a spot in the sky that’s about midway between Deneb, the brightest star in the constellation Cygnus the Swan, and Alderamin, the brightest star in the constellation Cepheus the King. See a chart of the position of Mars’ north celestial pole between the constellations Cygnus and Cepheus.

The southern sky view from Mars

Meanwhile, in the southern sky as seen from Mars, Kappa Velorum is only about 3 degrees from the Martian south celestial pole. That’s not as close as Polaris is to Earth’s north celestial pole, plus this star is only modestly bright, not nearly as bright as Polaris.

Future Mars colonists aren’t going to have a bright North Star – like our Polaris – to guide them.

On the other hand, if you were standing outside at night on the surface of Mars, you’d see some other cool stuff!

Dark landscape, greenish sky with tiny dot, and inset showing 2 dots labeled Earth and moon.
Earth and moon, as seen from Mars by the Curiosity rover in 2014. From Mars, you’d see both the Earth and moon with the eye alone. Image via NASA/ Wikimedia Commons (public domain). Read more about this image.

Can you see the moon orbiting the Earth from Mars?

As seen from Mars, you could see Earth’s moon orbiting around Earth once each month. From Earth, we can’t see any other planets’ satellites with the unaided eye, but this amazing sight on Mars would be visible to the eye alone. Both the Earth and the moon would appear starlike.

In general, the Earth as seen from Mars would somewhat mimic our view of Venus as seen from Earth. By that we mean that – like Venus in relationship to Earth – Earth in relationship to Mars is an inner planet. It orbits closer to the sun than Mars. Thus Earth as seen from Mars would be a morning or evening “star” – just as Venus is as seen from our world.

And although both the Earth and moon would appear as stars to the unaided eye, observers on Mars with telescopes would sometimes see them as crescent worlds, just as we see Venus.

So … no North Star for Mars. But Martian stargazers wouldn’t lack for things to see!

Irregular shadow about one fifth the apparent size of the sun crosses a solid white circle.
This series of images shows the Martian moon Phobos as it crossed in front of the sun, as seen by NASA’s Curiosity Mars rover on Tuesday, March 26, 2019 (Sol 2359). Image via NASA/JPL-Caltech.

Bottom line: Does planet Mars have a North Star akin to Earth’s North Star Polaris? No, there is not a Mars North Star. But Martian stargazers wouldn’t lack for things to see!

Read more: Astronomy on Mars

The post Is there a North Star for Mars? first appeared on EarthSky.



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North Star for Mars: Sunset on Mars. View full of dust. Tiny sun with dark land in foreground.
As the sun sets over the stark Martian landscape, stars come into view. Is there a North Star for Mars? Image via Spirit Mars rover, 2005/ NASA.

The 2025 EarthSky Lunar Calendar is now available! Makes a great gift. Get yours today!

North Star and South Star

We sometimes get this question. The North Star for Earth is Polaris. Does our next-door neighbor planet, Mars, have the same North Star as Earth? If not, does Mars have a star located more or less above its north pole?

Let’s talk about what we mean by North Star. Every planet in our solar system spins on its axis. Earth’s spin is what defines the length of our day of approximately 24 hours. If you continue the imaginary line of a planet’s axis out into space – in a northern direction as measured from earthly north – it might point to a star that’s visible to the eye. Or it might not. We call such stars pole stars, or North Stars. On Earth, that northern pole star – less than a degree from the north celestial pole – is the beloved star Polaris. Scouts and hikers know you can use Polaris to find the direction north when compasses fail.

Meanwhile, Earth’s Southern Hemisphere doesn’t have a comparable South Star. The nearest visible star to the south celestial pole of Earth is about 9 degrees away.

Illustration of the orbits of Earth and Mars around the sun.
Artist’s illustration of the relative tilts of the orbits of Earth and Mars, Earth doesn’t orbit exactly upright with respect to our orbit around the sun. Instead, Earth’s tilt is about 23 1/2 degrees. Meanwhile, Mars’ tilt is about 25 degrees. What’s more, the rotational axes of the Earth and Mars don’t tilt in the same direction, as in this illustration. For both reasons – different amount of tilt, and different direction of tilt – Mars doesn’t have the same North Star as Earth. Image via NASA.

A North Star for Mars?

So, does Mars have a North or South Star? The answer is … not in any satisfying way. There’s no bright North Star, and only a modestly-bright South Star, for Mars.

In the northern sky as seen from Mars, the best candidate for a North Star is located on Mars’ sky dome about 1/2 degree from Mars’ north celestial pole. That’s closer than Polaris is to Earth’s north celestial pole, but, while Polaris is relatively bright (50th brightest of all stars in the night sky), the star near Mars’ north celestial pole is faint.

In fact, this star is barely within the limit of visibility to the eye alone.

Mars’ north pole points to a spot in the sky that’s about midway between Deneb, the brightest star in the constellation Cygnus the Swan, and Alderamin, the brightest star in the constellation Cepheus the King. See a chart of the position of Mars’ north celestial pole between the constellations Cygnus and Cepheus.

The southern sky view from Mars

Meanwhile, in the southern sky as seen from Mars, Kappa Velorum is only about 3 degrees from the Martian south celestial pole. That’s not as close as Polaris is to Earth’s north celestial pole, plus this star is only modestly bright, not nearly as bright as Polaris.

Future Mars colonists aren’t going to have a bright North Star – like our Polaris – to guide them.

On the other hand, if you were standing outside at night on the surface of Mars, you’d see some other cool stuff!

Dark landscape, greenish sky with tiny dot, and inset showing 2 dots labeled Earth and moon.
Earth and moon, as seen from Mars by the Curiosity rover in 2014. From Mars, you’d see both the Earth and moon with the eye alone. Image via NASA/ Wikimedia Commons (public domain). Read more about this image.

Can you see the moon orbiting the Earth from Mars?

As seen from Mars, you could see Earth’s moon orbiting around Earth once each month. From Earth, we can’t see any other planets’ satellites with the unaided eye, but this amazing sight on Mars would be visible to the eye alone. Both the Earth and the moon would appear starlike.

In general, the Earth as seen from Mars would somewhat mimic our view of Venus as seen from Earth. By that we mean that – like Venus in relationship to Earth – Earth in relationship to Mars is an inner planet. It orbits closer to the sun than Mars. Thus Earth as seen from Mars would be a morning or evening “star” – just as Venus is as seen from our world.

And although both the Earth and moon would appear as stars to the unaided eye, observers on Mars with telescopes would sometimes see them as crescent worlds, just as we see Venus.

So … no North Star for Mars. But Martian stargazers wouldn’t lack for things to see!

Irregular shadow about one fifth the apparent size of the sun crosses a solid white circle.
This series of images shows the Martian moon Phobos as it crossed in front of the sun, as seen by NASA’s Curiosity Mars rover on Tuesday, March 26, 2019 (Sol 2359). Image via NASA/JPL-Caltech.

Bottom line: Does planet Mars have a North Star akin to Earth’s North Star Polaris? No, there is not a Mars North Star. But Martian stargazers wouldn’t lack for things to see!

Read more: Astronomy on Mars

The post Is there a North Star for Mars? first appeared on EarthSky.



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Leonid meteor shower: All you need to know in 2024

Earth's globe with lines pointing towards the moon, sun and meteors overhead.
The 2024 Leonid meteor shower, seen in earth mode (above the earth’s surface, looking down). Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

In 2024, the famous Leonid meteor shower will compete with moonlight from a waning gibbous moon on the shower’s peak morning, November 18. You might also try watching on the morning of November 17.

Mid-November meteors … the Leonids

Predicted peak: The peak is predicted** for 5 UTC on November 18, 2024.
When to watch: Watch late on the night of November 17 until dawn on November 18. The morning of November 17 might be worthwhile, too.
Duration of shower: November 3 through December 2.
Radiant: Rises around midnight, highest in the sky at dawn.
Nearest moon phase: In 2024, the full moon falls at 21:29 UTC on November 15. So the bright waning gibbous moon will wash out some meteors in 2024. Here are some tips for watching the Leonids in moonlight.
Expected meteors at peak, under ideal conditions: Under a dark sky with no moon, you might see 10 to 15 Leonid meteors per hour.
Note: The famous Leonid meteor shower produced one of the greatest meteor storms in living memory. Rates were as high as thousands of meteors per minute during a 15-minute span on the morning of November 17, 1966. That night, Leonid meteors did, briefly, fall like rain. Some who witnessed it had a strong impression of Earth moving through space, fording the meteor stream. Leonid meteor storms sometimes recur in cycles of 33 to 34 years. But the Leonids around the turn of the century – while wonderful for many observers – did not match the shower of 1966. And, in most years, the Lion whimpers rather than roars.

Report a fireball (very bright meteor) to the American Meteor Society: it’s fun and easy!

Find a place to watch at EarthSky’s Best Places to Stargaze page.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

The parent comet of the Leonid meteor shower

From the late, great Don Machholz (1952-2022), who discovered 12 comets …

Periodic Comet Tempel-Tuttle, officially known as 55P/Temple-Tuttle, is responsible for the Leonid meteor shower. William Tempel of Marseille Observatory in France discovered this comet on the evening of December 19, 1865. He found the comet in the northern sky, located in a part of the sky under the North Star, near the star Beta Ursae Minoris.

Word of the comet discovery became known throughout Europe, but the news had not yet spread to the United States. Horace Tuttle of Harvard College Observatory picked up the comet 17 days later, on the evening of January 5, 1866. Because this was an independent discovery, Tuttle’s name was added to the comet. Based upon the measurements during this visit of the comet, scientists calculated an orbit of 33.17 years. Astronomers quickly realized that the meteor storms and showers which occurred in mid-November of each year were the result of this comet.

One would think that there would be great interest in recovering this comet as it came back to the earth’s vicinity in 1899. But there wasn’t much interest in seeing the comet, everyone wanted to see a meteor storm. So, observers missed the comet in 1899. Also missing was a great meteor shower that year.

Scientists expected the next return in 1932. The observatories, using photographic plates with narrow field-of-view telescopes, missed it then too. And again, a major meteor shower did not materialize.

The comet was recovered in 1965

The comet was finally recovered in 1965. The brightest the comet got that year was 16th magnitude, visible only in very large telescopes. A spectacular meteor storm followed in 1966. On the next return, in early 1998, the comet was bright enough that you could see it in binoculars. This pass produced additional impressive meteor showers in 1999-2001. 55P/Temple-Tuttle is due back in early 2031.

With so much anticipation with the 1998 return and the expected meteor storms, several astronomers calculated the exact time and intensity of the storm. And they were accurate. This was the first instance of correct predictions. It is done by analyzing filaments of material expelled from each trip of the comet through the inner solar system. Quite often, a filament left behind by the comet hundreds of years ago will intersect the earth and produce a fabulous shower.

The Leonids: a meteor shower that revolutionized meteor science.

Note: This article, Leonids 1901-2100, gives specific meteor predictions for each year for this shower from the year 2001 to 2100.

The radiant of the Leonids

Star chart of constellation Leo with radial arrows indicating source of Leonid meteor shower.
Leonids stream from a single point in the sky – their radiant point – in the constellation Leo the Lion. Leo rises just before midnight in mid-November. Regulus, the brightest star in Leo the, dots a backwards question mark of stars known as the Sickle.
Sky chart with radial lines in the constellation Leo, grid lines, and several labeled stars.
The 2024 Leonid meteor shower, seen in sky mode (from the the Earth’s surface, looking up). On the morning of November 17, 2024, the radiant appears to originate inside the Sickle of Leo the Lion. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Which direction should I look to see the Leonid meteor shower?

Meteors in annual showers get their names from the point in the starry sky from which they appear to radiate. This shower’s name comes from the constellation Leo the Lion, because these meteors radiate outward from the vicinity of stars representing the Lion’s Mane.

If you trace the paths of Leonid meteors backward on the sky’s dome, they do seem to stream from near the star Algieba in the constellation Leo. The point in the sky from which they appear to radiate is the radiant point. This radiant point is an optical illusion. It’s like standing on railroad tracks and peering off into the distance to see the tracks converge. The illusion of the radiant point comes from the fact that the meteors – much like the railroad tracks – are moving on parallel paths.

In recent years, people have gotten the mistaken idea that you must know the whereabouts of a meteor shower’s radiant point in order to watch the meteor shower. You don’t need to. The meteors often don’t become visible until they are 30 degrees or so from their radiant point. They are streaking out from the radiant in all directions.

Thus, the Leonid meteors – like meteors in all annual showers – will appear in all parts of the sky.

Etchings of meteors as streaks in the sky over Niagara Falls and a scene with people looking up at meteors.
Old woodcuts depicting the 1833 Leonid meteor storm known as “the night the stars fell.” Image via Wikimedia (public domain).

A history of meteor storms

Scientists don’t expect a Leonid meteor storm this year. Most astronomers say you need more than 1,000 meteors an hour to consider a shower a storm. That’s far from the 10 to 15 meteors per hour the Leonids deliver in average years.

The Leonid shower is famous for producing meteor storms, though. The parent comet, Tempel-Tuttle, completes a single orbit around the sun about once every 33 years. It releases fresh material every time it approaches the sun. Since the 19th century, skywatchers have looked for Leonid meteor storms about every 33 years, beginning with the meteor storm of 1833, which witnesses said produced more than 100,000 meteors an hour.

The next great Leonid storms were about 33 years later, in 1866 and 1867. In 1899, a meteor storm did not materialize. In fact, the anticipation of a great meteor storm was so high, and the results so disappointing, that many astronomers felt it was the worst blow ever suffered by astronomy in the eyes of the public.

12 small objects streaking toward Earth as seen from orbit in black and white.
Leonid meteors viewed from space in 1997. Image via NASA.

Some Leonid meteor storms last century

Not until 1966 did the next spectacular Leonid storm occur, this time over the Americas. In 1966, observers in the southwest United States reported seeing 40 to 50 meteors per second (that’s 2,400 to 3,000 meteors per minute) during a span of 15 minutes on the morning of November 17, 1966.

In 2001, another great Leonid meteor storm occurred (though not as great as 1966). Spaceweather.com reported:

The display began on Sunday morning, November 18, when Earth glided into a dust cloud shed by Comet Tempel-Tuttle in 1766. Thousands of meteors per hour rained over North America and Hawaii. Then, on Monday morning November 19 (local time in Asia), it happened again: Earth entered a second cometary debris cloud from Tempel-Tuttle. Thousands more Leonids then fell over East Asian countries and Australia.

View SpaceWeather’s 2001 Leonid meteor gallery.

Sky filled with very, very many stars with long streaks for each; 1830s people out looking up.
The night the stars fell. Engraving by Adolf Vollmy (1889). Image via Wikimedia Commons (public domain).

The Leonid meteor shower of 1833

Adolf Vollmy produced the famous engraving above of the 1833 Leonid meteor shower for the Adventist book “Bible Readings for the Home Circle.” It’s based on a painting by Swiss artist Karl Jauslin, which, in turn, was based on a first-person account of the 1833 storm by a minister, Joseph Harvey Waggoner, who saw the 1833 shower on his way from Florida to New Orleans.

In that famous shower, hundreds of thousands of meteors per hour fell. It was the first recorded meteor storm of modern times.

Leonid meteors from the EarthSky Community

Two thin green horizontal streaks in dark starry sky.
View larger to see the colors better. | Eliot Herman in Tucson, Arizona, shared this double Leonid meteor photo, captured 2 days before the peak of the shower in 2018. Eliot commented, “The Leonids are the greenest meteors I see.” And he has seen a lot of meteors!

Bottom line: In 2024, watch for Leonids after midnight until dawn on November 18. The radiant point rises around midnight and is highest in the sky at dawn. A waning gibbous moon will interfere with Leonid meteors this year.

**Predicted peak times and dates for meteor showers are from the American Meteor Society. Note that meteor shower peak times can vary.

EarthSky’s meteor shower guide for 2024

EarthSky’s night sky guide: Visible planets and more

Meteor showers: Tips for watching the show

The post Leonid meteor shower: All you need to know in 2024 first appeared on EarthSky.



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Earth's globe with lines pointing towards the moon, sun and meteors overhead.
The 2024 Leonid meteor shower, seen in earth mode (above the earth’s surface, looking down). Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

In 2024, the famous Leonid meteor shower will compete with moonlight from a waning gibbous moon on the shower’s peak morning, November 18. You might also try watching on the morning of November 17.

Mid-November meteors … the Leonids

Predicted peak: The peak is predicted** for 5 UTC on November 18, 2024.
When to watch: Watch late on the night of November 17 until dawn on November 18. The morning of November 17 might be worthwhile, too.
Duration of shower: November 3 through December 2.
Radiant: Rises around midnight, highest in the sky at dawn.
Nearest moon phase: In 2024, the full moon falls at 21:29 UTC on November 15. So the bright waning gibbous moon will wash out some meteors in 2024. Here are some tips for watching the Leonids in moonlight.
Expected meteors at peak, under ideal conditions: Under a dark sky with no moon, you might see 10 to 15 Leonid meteors per hour.
Note: The famous Leonid meteor shower produced one of the greatest meteor storms in living memory. Rates were as high as thousands of meteors per minute during a 15-minute span on the morning of November 17, 1966. That night, Leonid meteors did, briefly, fall like rain. Some who witnessed it had a strong impression of Earth moving through space, fording the meteor stream. Leonid meteor storms sometimes recur in cycles of 33 to 34 years. But the Leonids around the turn of the century – while wonderful for many observers – did not match the shower of 1966. And, in most years, the Lion whimpers rather than roars.

Report a fireball (very bright meteor) to the American Meteor Society: it’s fun and easy!

Find a place to watch at EarthSky’s Best Places to Stargaze page.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

The parent comet of the Leonid meteor shower

From the late, great Don Machholz (1952-2022), who discovered 12 comets …

Periodic Comet Tempel-Tuttle, officially known as 55P/Temple-Tuttle, is responsible for the Leonid meteor shower. William Tempel of Marseille Observatory in France discovered this comet on the evening of December 19, 1865. He found the comet in the northern sky, located in a part of the sky under the North Star, near the star Beta Ursae Minoris.

Word of the comet discovery became known throughout Europe, but the news had not yet spread to the United States. Horace Tuttle of Harvard College Observatory picked up the comet 17 days later, on the evening of January 5, 1866. Because this was an independent discovery, Tuttle’s name was added to the comet. Based upon the measurements during this visit of the comet, scientists calculated an orbit of 33.17 years. Astronomers quickly realized that the meteor storms and showers which occurred in mid-November of each year were the result of this comet.

One would think that there would be great interest in recovering this comet as it came back to the earth’s vicinity in 1899. But there wasn’t much interest in seeing the comet, everyone wanted to see a meteor storm. So, observers missed the comet in 1899. Also missing was a great meteor shower that year.

Scientists expected the next return in 1932. The observatories, using photographic plates with narrow field-of-view telescopes, missed it then too. And again, a major meteor shower did not materialize.

The comet was recovered in 1965

The comet was finally recovered in 1965. The brightest the comet got that year was 16th magnitude, visible only in very large telescopes. A spectacular meteor storm followed in 1966. On the next return, in early 1998, the comet was bright enough that you could see it in binoculars. This pass produced additional impressive meteor showers in 1999-2001. 55P/Temple-Tuttle is due back in early 2031.

With so much anticipation with the 1998 return and the expected meteor storms, several astronomers calculated the exact time and intensity of the storm. And they were accurate. This was the first instance of correct predictions. It is done by analyzing filaments of material expelled from each trip of the comet through the inner solar system. Quite often, a filament left behind by the comet hundreds of years ago will intersect the earth and produce a fabulous shower.

The Leonids: a meteor shower that revolutionized meteor science.

Note: This article, Leonids 1901-2100, gives specific meteor predictions for each year for this shower from the year 2001 to 2100.

The radiant of the Leonids

Star chart of constellation Leo with radial arrows indicating source of Leonid meteor shower.
Leonids stream from a single point in the sky – their radiant point – in the constellation Leo the Lion. Leo rises just before midnight in mid-November. Regulus, the brightest star in Leo the, dots a backwards question mark of stars known as the Sickle.
Sky chart with radial lines in the constellation Leo, grid lines, and several labeled stars.
The 2024 Leonid meteor shower, seen in sky mode (from the the Earth’s surface, looking up). On the morning of November 17, 2024, the radiant appears to originate inside the Sickle of Leo the Lion. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Which direction should I look to see the Leonid meteor shower?

Meteors in annual showers get their names from the point in the starry sky from which they appear to radiate. This shower’s name comes from the constellation Leo the Lion, because these meteors radiate outward from the vicinity of stars representing the Lion’s Mane.

If you trace the paths of Leonid meteors backward on the sky’s dome, they do seem to stream from near the star Algieba in the constellation Leo. The point in the sky from which they appear to radiate is the radiant point. This radiant point is an optical illusion. It’s like standing on railroad tracks and peering off into the distance to see the tracks converge. The illusion of the radiant point comes from the fact that the meteors – much like the railroad tracks – are moving on parallel paths.

In recent years, people have gotten the mistaken idea that you must know the whereabouts of a meteor shower’s radiant point in order to watch the meteor shower. You don’t need to. The meteors often don’t become visible until they are 30 degrees or so from their radiant point. They are streaking out from the radiant in all directions.

Thus, the Leonid meteors – like meteors in all annual showers – will appear in all parts of the sky.

Etchings of meteors as streaks in the sky over Niagara Falls and a scene with people looking up at meteors.
Old woodcuts depicting the 1833 Leonid meteor storm known as “the night the stars fell.” Image via Wikimedia (public domain).

A history of meteor storms

Scientists don’t expect a Leonid meteor storm this year. Most astronomers say you need more than 1,000 meteors an hour to consider a shower a storm. That’s far from the 10 to 15 meteors per hour the Leonids deliver in average years.

The Leonid shower is famous for producing meteor storms, though. The parent comet, Tempel-Tuttle, completes a single orbit around the sun about once every 33 years. It releases fresh material every time it approaches the sun. Since the 19th century, skywatchers have looked for Leonid meteor storms about every 33 years, beginning with the meteor storm of 1833, which witnesses said produced more than 100,000 meteors an hour.

The next great Leonid storms were about 33 years later, in 1866 and 1867. In 1899, a meteor storm did not materialize. In fact, the anticipation of a great meteor storm was so high, and the results so disappointing, that many astronomers felt it was the worst blow ever suffered by astronomy in the eyes of the public.

12 small objects streaking toward Earth as seen from orbit in black and white.
Leonid meteors viewed from space in 1997. Image via NASA.

Some Leonid meteor storms last century

Not until 1966 did the next spectacular Leonid storm occur, this time over the Americas. In 1966, observers in the southwest United States reported seeing 40 to 50 meteors per second (that’s 2,400 to 3,000 meteors per minute) during a span of 15 minutes on the morning of November 17, 1966.

In 2001, another great Leonid meteor storm occurred (though not as great as 1966). Spaceweather.com reported:

The display began on Sunday morning, November 18, when Earth glided into a dust cloud shed by Comet Tempel-Tuttle in 1766. Thousands of meteors per hour rained over North America and Hawaii. Then, on Monday morning November 19 (local time in Asia), it happened again: Earth entered a second cometary debris cloud from Tempel-Tuttle. Thousands more Leonids then fell over East Asian countries and Australia.

View SpaceWeather’s 2001 Leonid meteor gallery.

Sky filled with very, very many stars with long streaks for each; 1830s people out looking up.
The night the stars fell. Engraving by Adolf Vollmy (1889). Image via Wikimedia Commons (public domain).

The Leonid meteor shower of 1833

Adolf Vollmy produced the famous engraving above of the 1833 Leonid meteor shower for the Adventist book “Bible Readings for the Home Circle.” It’s based on a painting by Swiss artist Karl Jauslin, which, in turn, was based on a first-person account of the 1833 storm by a minister, Joseph Harvey Waggoner, who saw the 1833 shower on his way from Florida to New Orleans.

In that famous shower, hundreds of thousands of meteors per hour fell. It was the first recorded meteor storm of modern times.

Leonid meteors from the EarthSky Community

Two thin green horizontal streaks in dark starry sky.
View larger to see the colors better. | Eliot Herman in Tucson, Arizona, shared this double Leonid meteor photo, captured 2 days before the peak of the shower in 2018. Eliot commented, “The Leonids are the greenest meteors I see.” And he has seen a lot of meteors!

Bottom line: In 2024, watch for Leonids after midnight until dawn on November 18. The radiant point rises around midnight and is highest in the sky at dawn. A waning gibbous moon will interfere with Leonid meteors this year.

**Predicted peak times and dates for meteor showers are from the American Meteor Society. Note that meteor shower peak times can vary.

EarthSky’s meteor shower guide for 2024

EarthSky’s night sky guide: Visible planets and more

Meteor showers: Tips for watching the show

The post Leonid meteor shower: All you need to know in 2024 first appeared on EarthSky.



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1st intentional signal to space sent by Arecibo 50 years ago

Signal to space: Many small figures made up of little squares.
On November 16, 1974, the Arecibo Observatory beamed the 1st intentional signal to space. Image via Wikimedia Commons. Click here for an explanation of each part of the message.

1st intentional signal to space in 1974

On November 16, 1974, astronomers used the Arecibo telescope in Puerto Rico to beam out the most powerful broadcast ever deliberately sent to space. They said the goal was to contact alien life. And some applauded it, but others didn’t. On the plus side, it reminded people that Earth likely isn’t the only planet in the Milky Way where intelligent life has evolved. But others felt – if alien civilizations do exist out there – we shouldn’t call attention to ourselves.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

The message in our signal to space

The message was designed by Cornell astronomy professor Frank Drake with input from other scientists including Carl Sagan. So, the final result was a simple and elegant broadcast. Basically, it consisted of a pattern of binary numbers. This message contained information about the basic chemicals of life and the structure of DNA. Plus, it included Earth’s place in our solar system and even a stick figure of a human.

Large dish in the ground with 3 towers and cables leading to receiver above middle of dish.
The Arecibo radio telescope in Puerto Rico broadcast the 1st intentional radio signal into space in 1974. Image via Wikimedia Commons.

Sending the Arecibo message

It took three minutes to send 1,679 bits of information, a snail’s pace compared to modern computer modems. And according to the SETI Institute:

The broadcast was particularly powerful because it used Arecibo’s megawatt transmitter attached to its 1,000 feet (305 meter) antenna. The latter concentrates the transmitter energy by beaming it into a very small patch of sky. The emission was equivalent to a 20 trillion-watt omnidirectional broadcast, and would be detectable by a SETI experiment just about anywhere in the galaxy, assuming a receiving antenna similar in size to Arecibo’s.

In fact, the 1974 signal went out in the direction of M13, a globular star cluster orbiting the center of our Milky Way galaxy. Basically, it was chosen because it’s a large collection of stars and was available in the sky at the time and place of the ceremony.

Also, globular star clusters are very far away. For instance, M13 is about 25,000 light-years from Earth.

And now, the 1974 signal is 50 light-years away from us.

By the way, the Arecibo radio telescope collapsed in 2020 when its 900-ton receiver platform came loose from its cables and fell onto the reflector dish more than 400 feet (120 meters) below.

Read more: Video shows Arecibo telescope crash

Bottom line: Iconic Arecibo telescope is no longer operational, but its legacy lives on. Fifty years ago, on November 16, 1974, Arecibo sent our first intentional signal to space. What do you think? Should we be advertising our presence in space?

The post 1st intentional signal to space sent by Arecibo 50 years ago first appeared on EarthSky.



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Signal to space: Many small figures made up of little squares.
On November 16, 1974, the Arecibo Observatory beamed the 1st intentional signal to space. Image via Wikimedia Commons. Click here for an explanation of each part of the message.

1st intentional signal to space in 1974

On November 16, 1974, astronomers used the Arecibo telescope in Puerto Rico to beam out the most powerful broadcast ever deliberately sent to space. They said the goal was to contact alien life. And some applauded it, but others didn’t. On the plus side, it reminded people that Earth likely isn’t the only planet in the Milky Way where intelligent life has evolved. But others felt – if alien civilizations do exist out there – we shouldn’t call attention to ourselves.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

The message in our signal to space

The message was designed by Cornell astronomy professor Frank Drake with input from other scientists including Carl Sagan. So, the final result was a simple and elegant broadcast. Basically, it consisted of a pattern of binary numbers. This message contained information about the basic chemicals of life and the structure of DNA. Plus, it included Earth’s place in our solar system and even a stick figure of a human.

Large dish in the ground with 3 towers and cables leading to receiver above middle of dish.
The Arecibo radio telescope in Puerto Rico broadcast the 1st intentional radio signal into space in 1974. Image via Wikimedia Commons.

Sending the Arecibo message

It took three minutes to send 1,679 bits of information, a snail’s pace compared to modern computer modems. And according to the SETI Institute:

The broadcast was particularly powerful because it used Arecibo’s megawatt transmitter attached to its 1,000 feet (305 meter) antenna. The latter concentrates the transmitter energy by beaming it into a very small patch of sky. The emission was equivalent to a 20 trillion-watt omnidirectional broadcast, and would be detectable by a SETI experiment just about anywhere in the galaxy, assuming a receiving antenna similar in size to Arecibo’s.

In fact, the 1974 signal went out in the direction of M13, a globular star cluster orbiting the center of our Milky Way galaxy. Basically, it was chosen because it’s a large collection of stars and was available in the sky at the time and place of the ceremony.

Also, globular star clusters are very far away. For instance, M13 is about 25,000 light-years from Earth.

And now, the 1974 signal is 50 light-years away from us.

By the way, the Arecibo radio telescope collapsed in 2020 when its 900-ton receiver platform came loose from its cables and fell onto the reflector dish more than 400 feet (120 meters) below.

Read more: Video shows Arecibo telescope crash

Bottom line: Iconic Arecibo telescope is no longer operational, but its legacy lives on. Fifty years ago, on November 16, 1974, Arecibo sent our first intentional signal to space. What do you think? Should we be advertising our presence in space?

The post 1st intentional signal to space sent by Arecibo 50 years ago first appeared on EarthSky.



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Some tropical mammals shy away from the full moon

Full moon rising over a misty rainforest. Some tropical mammals, like those in the Indonesian rainforest, avoid the moonlight.
View at EarthSky Community Photos. | Roosevelt Silva captured this setting full moon over a misty rainforest in Brazil on May 26, 2021. Thank you, Roosevelt! Scientists recently discovered that some tropical mammals, like those in Brazilian tropical forests, avoid the moonlight.
  • Many mammals in tropical forests adjust their behavior based on moon phases, with some species becoming less active during the full moon.
  • Using wildlife cameras, researchers observed that about 30% of mammals in these habitats are less active when the moon is full, while 20% are drawn to the moonlight.
  • The study highlights concerns about how increasing artificial light and forest canopy loss may disrupt animal behavior and interactions in tropical ecosystems.
  • The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Some tropical mammals avoid the full moon

    On a night like tonight – when there’s a full moon in the sky – the landscape is lit by bright moonlight. And you might think mammals living on the floor of tropical forests would welcome the moonlight. After all, it helps them see better. But scientists at the Norwegian University of Life Sciences studied the behavior of animals in the tropics under varying conditions of moonlight. They said on October 15, 2024, that – while some tropical mammals do appear more active under bright moonlight – an even larger percentage is less active when the moon is full.

    The researchers published their findings in the peer-reviewed Proceedings of the Royal Society B on October 16, 2024.

    Nighttime lighting affects tropical mammals

    Scientists don’t know a lot about how tropical mammals behave under different levels of moonlight. Their habitat – the floors of tropical forests under a thick canopy of leaves – are some of the darkest places on the planet at night.

    So scientists used automatic wildlife cameras to observe how mammals behaved during the night under different phases of the moon. They found at least half of the mammal species altered their activity around the full moon. Some became less active, in an effort to be inconspicuous and avoid predators.

    Richard Bischof of the Norwegian University of Life Sciences said:

    Imagine playing hide-and-seek in a dark room, and then somebody lights a candle. The light, even if it is weak, may make it easier for you to find your way around the room. But if you are the one hiding, you suddenly become a lot easier to detect.

    A large rodent with body stripes on the forest floor in a black and white image.
    Some tropical mammals, such as this paca, avoid the full moon and are less active when there is more moonlight. This image is from a wildlife camera. Image via Tropical Ecology Assessment and Monitoring Network/ Norwegian University of Life Sciences.

    Studying wild mammals in the dark

    The researchers studied 2.1 million wildlife camera images collected by the Tropical Ecology Assessment and Monitoring Network. The data came from 17 protected forests in Asia, Central America, South America and Africa.

    Of the 86 tropical mammal species they observed, the scientists found 12 of them strongly avoided moonlight at night. Just three species were drawn to moonlight.

    Bischof commented:

    These were the species with the most pronounced reactions. However, half of all the species responded to lunar phases. Either by changing their nocturnal habits, altering their overall activity levels, or both.

    Of the mammals that changed their behavior, the scientists discovered about 30% of them kept a low profile during the full moon. This was especially the case for nocturnal rodents. And about 20% of mammal species were drawn to the full moon.

    A dark image showing an armadillo on the forest floor.
    A nine-banded armadillo captured on a wildlife camera in the Caxiuana National Forest, Brazil. These armadillos are not fans of the full moon and are less active when there is more moonlight. This image is from a wildlife camera. Image via Tropical Ecology Assessment and Monitoring Network/ Norwegian University of Life Sciences.

    Why does this study matter?

    Tropical forests hold a significant portion of Earth’s biological diversity. These wild places are being increasingly fragmented and cleared. Logging reduces the forest canopy, allowing more light through. Artificial light from streetlamps and buildings can also influence animal activity.

    Bischof explained:

    The key takeaway from our research is that light affects animal behavior. It raises further questions about how changes in illumination affect species activity.

    The effect of increasing light on wild tropical mammals

    About 30% of tropical mammal species avoid the full moon, in part by becoming less active. A degraded tropical forest that lets in more light does not bode well for these species and could upset a delicate ecological balance.

    Bischof said:

    If these results extend to artificial light, loss of dark nights could curtail the amount of time animals invest into foraging and other important activities.

    There is a risk that we are fundamentally altering both species composition and species interactions in tropical forest communities through light conditions alone.

    Bottom line: Scientists have found that half of all mammal species in tropical forests change their behavior based on phases of the moon. About 1/3 of them avoid the full moon.

    Source: The moon’s influence on the activity of tropical forest mammals

    Via Norwegian University of Life Sciences

    Read more: Light pollution causes insects to lose track of the sky

    The post Some tropical mammals shy away from the full moon first appeared on EarthSky.



    from EarthSky https://ift.tt/JNmHf94
    Full moon rising over a misty rainforest. Some tropical mammals, like those in the Indonesian rainforest, avoid the moonlight.
    View at EarthSky Community Photos. | Roosevelt Silva captured this setting full moon over a misty rainforest in Brazil on May 26, 2021. Thank you, Roosevelt! Scientists recently discovered that some tropical mammals, like those in Brazilian tropical forests, avoid the moonlight.
  • Many mammals in tropical forests adjust their behavior based on moon phases, with some species becoming less active during the full moon.
  • Using wildlife cameras, researchers observed that about 30% of mammals in these habitats are less active when the moon is full, while 20% are drawn to the moonlight.
  • The study highlights concerns about how increasing artificial light and forest canopy loss may disrupt animal behavior and interactions in tropical ecosystems.
  • The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Some tropical mammals avoid the full moon

    On a night like tonight – when there’s a full moon in the sky – the landscape is lit by bright moonlight. And you might think mammals living on the floor of tropical forests would welcome the moonlight. After all, it helps them see better. But scientists at the Norwegian University of Life Sciences studied the behavior of animals in the tropics under varying conditions of moonlight. They said on October 15, 2024, that – while some tropical mammals do appear more active under bright moonlight – an even larger percentage is less active when the moon is full.

    The researchers published their findings in the peer-reviewed Proceedings of the Royal Society B on October 16, 2024.

    Nighttime lighting affects tropical mammals

    Scientists don’t know a lot about how tropical mammals behave under different levels of moonlight. Their habitat – the floors of tropical forests under a thick canopy of leaves – are some of the darkest places on the planet at night.

    So scientists used automatic wildlife cameras to observe how mammals behaved during the night under different phases of the moon. They found at least half of the mammal species altered their activity around the full moon. Some became less active, in an effort to be inconspicuous and avoid predators.

    Richard Bischof of the Norwegian University of Life Sciences said:

    Imagine playing hide-and-seek in a dark room, and then somebody lights a candle. The light, even if it is weak, may make it easier for you to find your way around the room. But if you are the one hiding, you suddenly become a lot easier to detect.

    A large rodent with body stripes on the forest floor in a black and white image.
    Some tropical mammals, such as this paca, avoid the full moon and are less active when there is more moonlight. This image is from a wildlife camera. Image via Tropical Ecology Assessment and Monitoring Network/ Norwegian University of Life Sciences.

    Studying wild mammals in the dark

    The researchers studied 2.1 million wildlife camera images collected by the Tropical Ecology Assessment and Monitoring Network. The data came from 17 protected forests in Asia, Central America, South America and Africa.

    Of the 86 tropical mammal species they observed, the scientists found 12 of them strongly avoided moonlight at night. Just three species were drawn to moonlight.

    Bischof commented:

    These were the species with the most pronounced reactions. However, half of all the species responded to lunar phases. Either by changing their nocturnal habits, altering their overall activity levels, or both.

    Of the mammals that changed their behavior, the scientists discovered about 30% of them kept a low profile during the full moon. This was especially the case for nocturnal rodents. And about 20% of mammal species were drawn to the full moon.

    A dark image showing an armadillo on the forest floor.
    A nine-banded armadillo captured on a wildlife camera in the Caxiuana National Forest, Brazil. These armadillos are not fans of the full moon and are less active when there is more moonlight. This image is from a wildlife camera. Image via Tropical Ecology Assessment and Monitoring Network/ Norwegian University of Life Sciences.

    Why does this study matter?

    Tropical forests hold a significant portion of Earth’s biological diversity. These wild places are being increasingly fragmented and cleared. Logging reduces the forest canopy, allowing more light through. Artificial light from streetlamps and buildings can also influence animal activity.

    Bischof explained:

    The key takeaway from our research is that light affects animal behavior. It raises further questions about how changes in illumination affect species activity.

    The effect of increasing light on wild tropical mammals

    About 30% of tropical mammal species avoid the full moon, in part by becoming less active. A degraded tropical forest that lets in more light does not bode well for these species and could upset a delicate ecological balance.

    Bischof said:

    If these results extend to artificial light, loss of dark nights could curtail the amount of time animals invest into foraging and other important activities.

    There is a risk that we are fundamentally altering both species composition and species interactions in tropical forest communities through light conditions alone.

    Bottom line: Scientists have found that half of all mammal species in tropical forests change their behavior based on phases of the moon. About 1/3 of them avoid the full moon.

    Source: The moon’s influence on the activity of tropical forest mammals

    Via Norwegian University of Life Sciences

    Read more: Light pollution causes insects to lose track of the sky

    The post Some tropical mammals shy away from the full moon first appeared on EarthSky.



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    Uranus at opposition on November 16-17, 2024

    Uranus at opposition: Green sphere that is a little lighter in the middle. Black background.
    View at EarthSky Community Photos. | Nancy Ricigliano in Long Island, New York, captured this image on November 13, 2023, and wrote: “When I found out Uranus was at opposition I figured I would give it a try. I was able to capture it in an eyepiece but had a difficult time finding it with my camera. It took me about an hour but I finally found it and was thrilled to capture this planet that is the 7th planet from the sun. The ice giant is surrounded by 13 faint rings and 27 small moons as it rotates at a nearly 90-degree angle from the plane of its orbit.” Thank you! When is Uranus at opposition in 2024? See below.

    Our planet Earth will swing between the sun and the 7th planet – Uranus – at 3 UTC on November 17, 2024. That means we’re now smack in the middle of the best time of year to see this outer planet. Have you ever spotted Uranus? Indeed, it’s theoretically possible to see with the eye alone. But, in practice, Uranus is tough to locate without optical aid. Still, it’s easier with Uranus opposite the sun. It’s rising in the east as the sun sets in the west, highest in the sky at midnight.

    The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Uranus at opposition

    When and where to watch in 2024: Uranus is theoretically visible to the unaided eye – assuming you have good eyesight – and you are under a dark sky. The planet is easily visible in good binoculars or a telescope, however. By the time of its November 17 opposition, Uranus is rising in the east at sunset and is visible all night. It’ll remain in the evening sky through April of 2025.
    Opposition for Uranus will fall at 3 UTC on November 17, 2024. That’s 10 p.m. CDT on November 16.
    Brightness at opposition: The 7th planet shines most brightly for 2024, at magnitude +5.6. In fact, Uranus shines at this brightness from about mid-October to mid-December. So, it should be possible to glimpse Uranus with the unaided eye, if you have dark-sky conditions. Find printable finder charts for Uranus here.
    Distance from Earth: Uranus is at its least distance from Earth for 2024, 2.6 light-hours or 18.6 AU from Earth.
    Constellation at opposition: At this 2024 opposition, Uranus is in front of the constellation Taurus the Bull.
    Through a telescope: Uranus appears as a tiny, greenish disk 3.8 arcseconds across. In addition, look for up to four moons of Uranus as well.
    Note: William Herschel discovered Uranus in 1781. It was the first planet to be discovered in modern times, and the first to be discovered with a telescope. It expanded the known limits of our solar system. Herschel called the new planet “the Georgium Sidus” (the Georgian Planet) in honor of King George III of England. However, the other planets were named from classical mythology. So the German astronomer Johann Elert Bode later suggested Uranus, in order to bring Uranus into conformity with the other planets’ names. In mythology, Uranus is the ancient Greek deity of the heavens, the earliest supreme god. His mythological granddaughter, Urania, is the goddess of astronomy. The name Uranus for this planet didn’t come into common use, however, until 1850.

    Quick facts about oppositions

    Opposition marks the middle of the best time of year to see an outer planet.

    Think of us on Earth, sweeping between the sun and Uranus in our smaller, faster orbit. Around the same time as Uranus reaches opposition, it is also making its closest approach to Earth.

    Read more about opposition

    Simple diagram of orbits of Earth and a superior planet.
    Opposition happens when Earth flies between an outer planet, like Uranus, and the sun. Illustration via Heavens-Above. Used with permission.

    For precise sun and Uranus rising times at your location:

    Old Farmer’s Almanac (U.S. and Canada)

    timeanddate.com (worldwide).

    Stellarium (online planetarium program)

    In-the-sky information and finder chart from your location

    How often is Uranus at opposition?

    Uranus is the 7th planet from our sun. A year on Uranus is 84.4 Earth-years long. So, because Uranus’s orbit around the sun is so gigantic, and because Earth whips around the sun so quickly in comparison, Uranus’s opposition date falls about four days later each year.

    2023 Uranus opposition – November 13
    2024 Uranus opposition – November 16
    2025 Uranus opposition – November 21
    2026 Uranus opposition – November 25

    Smooth, featureless pale blue ball on black background.
    Uranus as seen by Voyager 2 on January 14, 1986. Image via NASA/ JPL-Caltech.

    View from above the solar system, November 2024

    Circle with sun at center, planets around, and zodiac names on outer edge.
    Heliocentric view of solar system, November 2024. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

    Earth and Uranus at opposition

    Our planet Earth swings between the sun and Uranus on November 17, 2024, placing us squarely in the middle of the best time of year to see this outer planet. Why? Because in November 2024, Uranus is opposite the sun in our sky. It rises in the east as the sun sets in the west. November 17, 2024, is when Uranus reaches its yearly opposition.

    And because Uranus is opposite the sun in November 2024, it climbs highest for the night at midnight (midway between sunset and sunrise). So, Uranus stays out all night long. Also, around the time of opposition, Earth’s motion brings Uranus closest to Earth for 2024. The planet shines at its brightest in our sky. How bright is that? Not very bright.

    The fact is, even at its brightest, Uranus is still quite faint. Indeed, it’s barely perceptible as a dim speck of light to the unaided eye, even under dark skies. At a magnitude +5.6, Uranus shines no more brilliantly than the sky’s faintest visible stars. Given a dark sky free of light pollution, you might see Uranus with the eye alone. But you’ll need to have a good finder chart to know right where to look for this distant world in the constellation Taurus.

    Distance to Uranus

    At its closest point to Earth, Uranus is still twice as far away from us as its next-door neighbor, Saturn. At opposition, Uranus will be just shy of 19 astronomical units AU away from Earth and 20 AU from the sun. (One astronomical unit equals the average distance of Earth from the sun). Visit Heavens-Above to find out the present distance of Uranus and the other solar system planets.

    Other Uranus observing opportunities

    While opposition is mathematically the best time to view Uranus due to its nearness and brightness, another great opportunity is when the dim planet is near a brighter, closer planet, or near the moon. For example, when Venus or Mars passes close to distant Uranus as seen from our point of view, we get an easy guidepost to point us to the gas giant. The moon will be near Uranus on November 15 and 16, 2024, with the planet Jupiter nearby. And later, the moon will visit Uranus again on December 13, 2024.

    Deep blue sky with scattered stars, small circled dot labeled Uranus, and larger dot labeled Venus.
    View at EarthSky Community Photos. | Jim Bruzek of Dayton, Maryland, captured this image on March 30, 2023, and wrote: “Venus and Uranus at dusk from Dayton, Maryland.” Thank you, Jim!

    Bottom line: Uranus reaches opposition on November 16-17, 2024. At this time, it’s brightest for the year and visible to the eye under optimum observing conditions. Here’s how to see it.

    Read more: Seasons of Uranus, a sideways world with strange seasons

    Read more: Uranus discovered by accident in 1781

    The post Uranus at opposition on November 16-17, 2024 first appeared on EarthSky.



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    Uranus at opposition: Green sphere that is a little lighter in the middle. Black background.
    View at EarthSky Community Photos. | Nancy Ricigliano in Long Island, New York, captured this image on November 13, 2023, and wrote: “When I found out Uranus was at opposition I figured I would give it a try. I was able to capture it in an eyepiece but had a difficult time finding it with my camera. It took me about an hour but I finally found it and was thrilled to capture this planet that is the 7th planet from the sun. The ice giant is surrounded by 13 faint rings and 27 small moons as it rotates at a nearly 90-degree angle from the plane of its orbit.” Thank you! When is Uranus at opposition in 2024? See below.

    Our planet Earth will swing between the sun and the 7th planet – Uranus – at 3 UTC on November 17, 2024. That means we’re now smack in the middle of the best time of year to see this outer planet. Have you ever spotted Uranus? Indeed, it’s theoretically possible to see with the eye alone. But, in practice, Uranus is tough to locate without optical aid. Still, it’s easier with Uranus opposite the sun. It’s rising in the east as the sun sets in the west, highest in the sky at midnight.

    The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Uranus at opposition

    When and where to watch in 2024: Uranus is theoretically visible to the unaided eye – assuming you have good eyesight – and you are under a dark sky. The planet is easily visible in good binoculars or a telescope, however. By the time of its November 17 opposition, Uranus is rising in the east at sunset and is visible all night. It’ll remain in the evening sky through April of 2025.
    Opposition for Uranus will fall at 3 UTC on November 17, 2024. That’s 10 p.m. CDT on November 16.
    Brightness at opposition: The 7th planet shines most brightly for 2024, at magnitude +5.6. In fact, Uranus shines at this brightness from about mid-October to mid-December. So, it should be possible to glimpse Uranus with the unaided eye, if you have dark-sky conditions. Find printable finder charts for Uranus here.
    Distance from Earth: Uranus is at its least distance from Earth for 2024, 2.6 light-hours or 18.6 AU from Earth.
    Constellation at opposition: At this 2024 opposition, Uranus is in front of the constellation Taurus the Bull.
    Through a telescope: Uranus appears as a tiny, greenish disk 3.8 arcseconds across. In addition, look for up to four moons of Uranus as well.
    Note: William Herschel discovered Uranus in 1781. It was the first planet to be discovered in modern times, and the first to be discovered with a telescope. It expanded the known limits of our solar system. Herschel called the new planet “the Georgium Sidus” (the Georgian Planet) in honor of King George III of England. However, the other planets were named from classical mythology. So the German astronomer Johann Elert Bode later suggested Uranus, in order to bring Uranus into conformity with the other planets’ names. In mythology, Uranus is the ancient Greek deity of the heavens, the earliest supreme god. His mythological granddaughter, Urania, is the goddess of astronomy. The name Uranus for this planet didn’t come into common use, however, until 1850.

    Quick facts about oppositions

    Opposition marks the middle of the best time of year to see an outer planet.

    Think of us on Earth, sweeping between the sun and Uranus in our smaller, faster orbit. Around the same time as Uranus reaches opposition, it is also making its closest approach to Earth.

    Read more about opposition

    Simple diagram of orbits of Earth and a superior planet.
    Opposition happens when Earth flies between an outer planet, like Uranus, and the sun. Illustration via Heavens-Above. Used with permission.

    For precise sun and Uranus rising times at your location:

    Old Farmer’s Almanac (U.S. and Canada)

    timeanddate.com (worldwide).

    Stellarium (online planetarium program)

    In-the-sky information and finder chart from your location

    How often is Uranus at opposition?

    Uranus is the 7th planet from our sun. A year on Uranus is 84.4 Earth-years long. So, because Uranus’s orbit around the sun is so gigantic, and because Earth whips around the sun so quickly in comparison, Uranus’s opposition date falls about four days later each year.

    2023 Uranus opposition – November 13
    2024 Uranus opposition – November 16
    2025 Uranus opposition – November 21
    2026 Uranus opposition – November 25

    Smooth, featureless pale blue ball on black background.
    Uranus as seen by Voyager 2 on January 14, 1986. Image via NASA/ JPL-Caltech.

    View from above the solar system, November 2024

    Circle with sun at center, planets around, and zodiac names on outer edge.
    Heliocentric view of solar system, November 2024. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

    Earth and Uranus at opposition

    Our planet Earth swings between the sun and Uranus on November 17, 2024, placing us squarely in the middle of the best time of year to see this outer planet. Why? Because in November 2024, Uranus is opposite the sun in our sky. It rises in the east as the sun sets in the west. November 17, 2024, is when Uranus reaches its yearly opposition.

    And because Uranus is opposite the sun in November 2024, it climbs highest for the night at midnight (midway between sunset and sunrise). So, Uranus stays out all night long. Also, around the time of opposition, Earth’s motion brings Uranus closest to Earth for 2024. The planet shines at its brightest in our sky. How bright is that? Not very bright.

    The fact is, even at its brightest, Uranus is still quite faint. Indeed, it’s barely perceptible as a dim speck of light to the unaided eye, even under dark skies. At a magnitude +5.6, Uranus shines no more brilliantly than the sky’s faintest visible stars. Given a dark sky free of light pollution, you might see Uranus with the eye alone. But you’ll need to have a good finder chart to know right where to look for this distant world in the constellation Taurus.

    Distance to Uranus

    At its closest point to Earth, Uranus is still twice as far away from us as its next-door neighbor, Saturn. At opposition, Uranus will be just shy of 19 astronomical units AU away from Earth and 20 AU from the sun. (One astronomical unit equals the average distance of Earth from the sun). Visit Heavens-Above to find out the present distance of Uranus and the other solar system planets.

    Other Uranus observing opportunities

    While opposition is mathematically the best time to view Uranus due to its nearness and brightness, another great opportunity is when the dim planet is near a brighter, closer planet, or near the moon. For example, when Venus or Mars passes close to distant Uranus as seen from our point of view, we get an easy guidepost to point us to the gas giant. The moon will be near Uranus on November 15 and 16, 2024, with the planet Jupiter nearby. And later, the moon will visit Uranus again on December 13, 2024.

    Deep blue sky with scattered stars, small circled dot labeled Uranus, and larger dot labeled Venus.
    View at EarthSky Community Photos. | Jim Bruzek of Dayton, Maryland, captured this image on March 30, 2023, and wrote: “Venus and Uranus at dusk from Dayton, Maryland.” Thank you, Jim!

    Bottom line: Uranus reaches opposition on November 16-17, 2024. At this time, it’s brightest for the year and visible to the eye under optimum observing conditions. Here’s how to see it.

    Read more: Seasons of Uranus, a sideways world with strange seasons

    Read more: Uranus discovered by accident in 1781

    The post Uranus at opposition on November 16-17, 2024 first appeared on EarthSky.



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    The strange seasons of Uranus, a sideways world

    Seasons of Uranus: A light-blue shaded sphere with bright spot on it, plus white concentric rings around it.
    NASA released this Uranus image on April 6, 2023. It’s from the mighty Webb space telescope. In this zoomed-in view, you can see Uranus’ dusty rings and dynamic atmosphere. Notice anything strange about the rings? Yep. Uranus’ rings lie sideways with respect to the ring-and-moon planes of the other planets. Uranus is our solar system’s sideways planet. And that means its the seasons of Uranus are strange! Read more about them below. Image via NASA/ ESA/ CSA/ STScI/ J. DePasquale (STScI).

    The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Strange seasons of Uranus

    Uranus has bizarre seasons, at least from our earthly perspective. As we explore distant exoplanets – or think about moons or rocky asteroids in this solar system – who knows what range of differences we’ll find? But for the moment we do know this. Uranus has unusual seasons, in contrast to Earth and the other major known planets. It’s because Uranus’ spin axis lies nearly sideways with respect to the plane of its orbit around the sun. Compared to Mercury, Venus, Earth, Mars, Jupiter, Saturn and Neptune – all of which spin elegantly, nearly upright, as they orbit our local star – Uranus seems almost as if it’s rolling around the sun, like a rolling ball.

    Earth’s axis is tilted 23.5 degrees from perpendicular with respect to the plane of our orbit around the sun. Uranus’s axis is tilted at 98 degrees! So Uranus is tilted nearly sideways to the plane of the solar system, the single flat sheet of space in which nearly all the planets and moons orbit.

    And, speaking of its orbit, Uranus orbits 1.8 billion miles (2.9 billion km) from the sun. Therefore, Uranus takes a long time to orbit the sun once. Its year is 84 Earth-years long. That makes each of its four seasons 21 years long. That’s another reason we on Earth think of Uranus’ seasons as strange.

    Like Earth, Uranus has a nearly circular orbit, so it always remains at roughly the same distance from the sun. Unlike Mars – whose orbit is more elliptical than that of Earth or Uranus – Uranus’ distance from the sun isn’t a factor in its seasonal change.

    Instead, as on Earth, the planet’s tilt is what gives Uranus its four seasons.

    Extreme tilt means extreme seasons

    So think about how Uranus’ tilt affects its seasons, in contrast to earthly seasons. Here’s one difference. Earth’s tilt means our north and south polar regions have a midnight sun in summer and a long polar night in winter. Since Earth’s axis tilt is relatively small, those dark and bright times at Earth’s poles affect a relatively small part of our planet.

    But the tilt of Uranus’ spin axis – 98 degrees – is huge. As a result, in summer, one pole of Uranus plus a large section of that pole’s hemisphere faces the sun continuously for 21 years. Meanwhile, the other half of Uranus – the winter half – is in darkness for 21 years. That’s a long polar night, and a long midnight sun!

    Bizarre spring and fall on Uranus

    Spring and fall on Uranus are equally bizarre. Around the equinoxes on Uranus, sunlight strikes the equatorial region of the planet. During those seasons, the length of a day on Uranus plays an important role in its climate. Uranus spins on its axis about every 17 hours, 14 minutes. So its day-night cycle lasts that long.

    So, for much of the planet’s spring and fall, a large percentage of the planet has day and night about every 17 hours. It’s quite a contrast to the summer and winter seasons when half the planet is either in darkness or daylight.

    Seasons of Uranus: Diagram: Uranus at 4 positions in its orbit with axis pointing toward sun and parallel to orbit at different seasons.
    This diagram shows Uranus at four locations in its orbit. When Voyager 2 passed by in 1986, the planet’s south pole was facing the sun and the atmosphere did not show much activity. In 2007, the sun was shining over the planet’s equator, resulting in 17-hour day-night cycles. Earth- and space-based observatories revealed more activity in Uranus’ atmosphere, such as cloud features and atmospheric bands. Image via NASA/ ESA/ SETI/ M. Showalter.

    Smooth, featureless pale blue ball on black background.
    A blue and featureless Uranus, as seen by Voyager 2 in 1986. Voyager encountered Uranus during the planet’s southern hemisphere summer season. Image via NASA PhotoJournal.

    What we see from Earth and spacecraft

    The extreme seasonal changes cause dramatic shifts in Uranus’ cloud patterns. Earth- and space-based observatories have observed this change over decades of Uranus-watching. The Voyager 2 spacecraft is the only craft from Earth that has ever flown past Uranus. That was in 1986. Voyager 2 encountered this world during its southern hemisphere summer. The spacecraft saw Uranus as blue and featureless.

    In the years since Voyager 2’s flyby of Uranus, astronomical observing technologies have become more powerful. As Uranus moved in its 84-year orbit around the sun, we’ve seen the seasons on Uranus change.

    Since the Voyager 2 observations, Uranus has emerged from the grip of its decades-long winter/summer season. Its southern hemisphere autumn equinox occurred in 2007; that’s when the sun was shining above Uranus’ equator. Sunlight reached some latitudes for the first time in years. Light and warmth in the atmosphere triggered gigantic storms comparable in size to North America (but with temperatures of -300 Fahrenheit/-184 Celsius), visible as bright spots in the planet’s atmosphere.

    Following seasons of Uranus from Earth

    Around that time, Earth- and space-based telescopes revealed more clouds in the atmosphere of Uranus. Bands encircling the planet changed in size and brightness as sunlight struck parts of the planet for the first time in decades. Plus, a dark spot appeared – and more bright spots – which observers were able to follow for years.

    What more will we see in the decades and years ahead as Uranus moves toward the long winter/summer portion of its orbit once more?

    Blue striped planet with inset showing enlarged dark spot.
    The dark spot on Uranus, which appeared as the planet’s northern hemisphere approached its autumn equinox, was large enough to engulf 2/3 of the United States. Image via NASA/ ESA/ L. Sromovsky and P. Fry.
    Planet in space with thin ring and several moons. Planet has colorful bands and small red spots.
    This 2004 image of Uranus was taken using filters designed to isolate very specific wavelengths of light to bring out features – in this case, variations in the altitude and thickness of clouds – that would otherwise not be visible. Images of the area around the planet were enhanced to show the rings and some of the planet’s moons. Image via NASA/ Erich Karkoschka.

    Bottom line: The rotation axis of Uranus has a very large tilt that causes extreme seasonal changes. This results in increased activity in its atmosphere during the planet’s spring and fall seasons.

    Read more: Uranus at opposition on November 16-17, 2024

    Read more: Uranus discovered by accident in 1781

    The post The strange seasons of Uranus, a sideways world first appeared on EarthSky.



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    Seasons of Uranus: A light-blue shaded sphere with bright spot on it, plus white concentric rings around it.
    NASA released this Uranus image on April 6, 2023. It’s from the mighty Webb space telescope. In this zoomed-in view, you can see Uranus’ dusty rings and dynamic atmosphere. Notice anything strange about the rings? Yep. Uranus’ rings lie sideways with respect to the ring-and-moon planes of the other planets. Uranus is our solar system’s sideways planet. And that means its the seasons of Uranus are strange! Read more about them below. Image via NASA/ ESA/ CSA/ STScI/ J. DePasquale (STScI).

    The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Keep up with all phases of the moon every night of the year.

    Strange seasons of Uranus

    Uranus has bizarre seasons, at least from our earthly perspective. As we explore distant exoplanets – or think about moons or rocky asteroids in this solar system – who knows what range of differences we’ll find? But for the moment we do know this. Uranus has unusual seasons, in contrast to Earth and the other major known planets. It’s because Uranus’ spin axis lies nearly sideways with respect to the plane of its orbit around the sun. Compared to Mercury, Venus, Earth, Mars, Jupiter, Saturn and Neptune – all of which spin elegantly, nearly upright, as they orbit our local star – Uranus seems almost as if it’s rolling around the sun, like a rolling ball.

    Earth’s axis is tilted 23.5 degrees from perpendicular with respect to the plane of our orbit around the sun. Uranus’s axis is tilted at 98 degrees! So Uranus is tilted nearly sideways to the plane of the solar system, the single flat sheet of space in which nearly all the planets and moons orbit.

    And, speaking of its orbit, Uranus orbits 1.8 billion miles (2.9 billion km) from the sun. Therefore, Uranus takes a long time to orbit the sun once. Its year is 84 Earth-years long. That makes each of its four seasons 21 years long. That’s another reason we on Earth think of Uranus’ seasons as strange.

    Like Earth, Uranus has a nearly circular orbit, so it always remains at roughly the same distance from the sun. Unlike Mars – whose orbit is more elliptical than that of Earth or Uranus – Uranus’ distance from the sun isn’t a factor in its seasonal change.

    Instead, as on Earth, the planet’s tilt is what gives Uranus its four seasons.

    Extreme tilt means extreme seasons

    So think about how Uranus’ tilt affects its seasons, in contrast to earthly seasons. Here’s one difference. Earth’s tilt means our north and south polar regions have a midnight sun in summer and a long polar night in winter. Since Earth’s axis tilt is relatively small, those dark and bright times at Earth’s poles affect a relatively small part of our planet.

    But the tilt of Uranus’ spin axis – 98 degrees – is huge. As a result, in summer, one pole of Uranus plus a large section of that pole’s hemisphere faces the sun continuously for 21 years. Meanwhile, the other half of Uranus – the winter half – is in darkness for 21 years. That’s a long polar night, and a long midnight sun!

    Bizarre spring and fall on Uranus

    Spring and fall on Uranus are equally bizarre. Around the equinoxes on Uranus, sunlight strikes the equatorial region of the planet. During those seasons, the length of a day on Uranus plays an important role in its climate. Uranus spins on its axis about every 17 hours, 14 minutes. So its day-night cycle lasts that long.

    So, for much of the planet’s spring and fall, a large percentage of the planet has day and night about every 17 hours. It’s quite a contrast to the summer and winter seasons when half the planet is either in darkness or daylight.

    Seasons of Uranus: Diagram: Uranus at 4 positions in its orbit with axis pointing toward sun and parallel to orbit at different seasons.
    This diagram shows Uranus at four locations in its orbit. When Voyager 2 passed by in 1986, the planet’s south pole was facing the sun and the atmosphere did not show much activity. In 2007, the sun was shining over the planet’s equator, resulting in 17-hour day-night cycles. Earth- and space-based observatories revealed more activity in Uranus’ atmosphere, such as cloud features and atmospheric bands. Image via NASA/ ESA/ SETI/ M. Showalter.

    Smooth, featureless pale blue ball on black background.
    A blue and featureless Uranus, as seen by Voyager 2 in 1986. Voyager encountered Uranus during the planet’s southern hemisphere summer season. Image via NASA PhotoJournal.

    What we see from Earth and spacecraft

    The extreme seasonal changes cause dramatic shifts in Uranus’ cloud patterns. Earth- and space-based observatories have observed this change over decades of Uranus-watching. The Voyager 2 spacecraft is the only craft from Earth that has ever flown past Uranus. That was in 1986. Voyager 2 encountered this world during its southern hemisphere summer. The spacecraft saw Uranus as blue and featureless.

    In the years since Voyager 2’s flyby of Uranus, astronomical observing technologies have become more powerful. As Uranus moved in its 84-year orbit around the sun, we’ve seen the seasons on Uranus change.

    Since the Voyager 2 observations, Uranus has emerged from the grip of its decades-long winter/summer season. Its southern hemisphere autumn equinox occurred in 2007; that’s when the sun was shining above Uranus’ equator. Sunlight reached some latitudes for the first time in years. Light and warmth in the atmosphere triggered gigantic storms comparable in size to North America (but with temperatures of -300 Fahrenheit/-184 Celsius), visible as bright spots in the planet’s atmosphere.

    Following seasons of Uranus from Earth

    Around that time, Earth- and space-based telescopes revealed more clouds in the atmosphere of Uranus. Bands encircling the planet changed in size and brightness as sunlight struck parts of the planet for the first time in decades. Plus, a dark spot appeared – and more bright spots – which observers were able to follow for years.

    What more will we see in the decades and years ahead as Uranus moves toward the long winter/summer portion of its orbit once more?

    Blue striped planet with inset showing enlarged dark spot.
    The dark spot on Uranus, which appeared as the planet’s northern hemisphere approached its autumn equinox, was large enough to engulf 2/3 of the United States. Image via NASA/ ESA/ L. Sromovsky and P. Fry.
    Planet in space with thin ring and several moons. Planet has colorful bands and small red spots.
    This 2004 image of Uranus was taken using filters designed to isolate very specific wavelengths of light to bring out features – in this case, variations in the altitude and thickness of clouds – that would otherwise not be visible. Images of the area around the planet were enhanced to show the rings and some of the planet’s moons. Image via NASA/ Erich Karkoschka.

    Bottom line: The rotation axis of Uranus has a very large tilt that causes extreme seasonal changes. This results in increased activity in its atmosphere during the planet’s spring and fall seasons.

    Read more: Uranus at opposition on November 16-17, 2024

    Read more: Uranus discovered by accident in 1781

    The post The strange seasons of Uranus, a sideways world first appeared on EarthSky.



    from EarthSky https://ift.tt/jYEQpMv

    Galaxy’s south window looks into intergalactic space

    Galaxy's south window: Star chart outlining a blob-like shape with 1 star, Fomalhaut, labeled.
    Piscis Austrinus the Southern Fish is notable for its one bright star, Fomalhaut. When you look toward Fomalhaut, you are looking out our galaxy’s south window and into intergalactic space. By the way, the rest of the stars making up Piscis Austrinus are faint and difficult to see unless you have a dark sky. Chart via EarthSky.

    The 2025 EarthSky Lunar Calendar makes a great gift. Get yours today!

    Gazing toward our galaxy’s south window into Intergalactic space

    As you gaze toward the bright star Fomalhaut, you’ll be looking in the direction toward our galaxy’s south window. In other words, you’ll be looking away from the flat plane of our Milky Way, where most of our galaxy’s stars reside. And you’ll be looking in the direction toward one of the poles of our galaxy. Because, that’s where there are fewer stars, and beyond the Milky Way’s stars, there is intergalactic space.

    As a matter of fact, you might say we’re looking out the south window of the galaxy.

    Fomalhaut is the brightest star in the constellation Piscis Austrinus the Southern Fish.

    Beware, though. The other bright “star” in the area in 2024 is the planet Saturn. However, Saturn will be a creamy golden color and shining with a steady light.

    For more sky events, visit EarthSky’s night sky guide.

    To see a precise view from your location, try Stellarium Online.

    Saturn and Fomalhaut in the November evening sky.
    Saturn and the bright star Fomalhaut are the only 2 bright objects in that area of the sky. Chart via EarthSky.

    The Milky Way’s south galactic pole

    Sky chart showing 6 constellations. Constellation Sculptor (triangle shape) is in the middle, and the South Galactic Pole (circle with tick marks) is at the top left of Sculptor.
    The circle with tick marks indicates the position of the south galactic pole, just above the triangle shape of Sculptor. Chart via EarthSky.

    Why to find Fomalhaut? When you look at this star – sometimes called the Loneliest Star – you are looking some 90 degrees from the plane of our galaxy’s equator.

    Our Milky Way galaxy is round and flat, like a pancake. When you look toward Fomalhaut, you’re looking away from the pancake, and out the south window of the galaxy. In other words, we’re looking away from the star-packed disk of the galaxy, into intergalactic space and the realm of galaxies.

    Want the exact location of the south galactic pole? It lies east of Fomalhaut, in the faint constellation Sculptor. See the chart above.

    Finding Fomalhaut

    Fomalhaut is a very noticeable star because it’s in a region of the heavens where there are few stars bright enough to be seen with the eye. That’s why Fomalhaut is often said to be the loneliest star. If you’re not sure, try using the Great Square of Pegasus to confirm the star you see is Fomalhaut. See the chart below. By the way, in 2024, Saturn will lie between the Great Square and Fomalhaut.

    Our galaxy’s south window from the Northern Hemisphere:

    The Great Square of Pegasus appears high in the south to overhead by around 7 to 8 p.m. local time in late November and early December. This large asterism really does look like a large square pattern, with four medium-bright stars marking the corners. Draw a line through the Great Square’s two westernmost (or right-hand) stars, and extend that line southward to land on Fomalhaut.

    From the Southern Hemisphere:

    The Great Square of Pegasus appears low in the northern sky. Then draw a line from the two westernmost stars upward to Fomalhaut. So, just take the chart below, and turn it upside-down!

    hart showing Great Square of Pegasus (at the top of the chart) in relationship to Fomalhaut (bottom right) and Sculptor (bottom left).
    The 4 stars making up the Great Square of Pegasus. You can use the Great Square to find the star Fomalhaut. Chart via EarthSky.

    Bottom line: Use the Great Square of Pegasus to locate Fomalhaut. And once you’ve found Fomalhaut, you’re on your way to looking out our galaxy’s south window into intergalactic space.

    Easily locate stars and constellations during any day and time with EarthSky’s Planisphere.

    The post Galaxy’s south window looks into intergalactic space first appeared on EarthSky.



    from EarthSky https://ift.tt/cn0w3Xx
    Galaxy's south window: Star chart outlining a blob-like shape with 1 star, Fomalhaut, labeled.
    Piscis Austrinus the Southern Fish is notable for its one bright star, Fomalhaut. When you look toward Fomalhaut, you are looking out our galaxy’s south window and into intergalactic space. By the way, the rest of the stars making up Piscis Austrinus are faint and difficult to see unless you have a dark sky. Chart via EarthSky.

    The 2025 EarthSky Lunar Calendar makes a great gift. Get yours today!

    Gazing toward our galaxy’s south window into Intergalactic space

    As you gaze toward the bright star Fomalhaut, you’ll be looking in the direction toward our galaxy’s south window. In other words, you’ll be looking away from the flat plane of our Milky Way, where most of our galaxy’s stars reside. And you’ll be looking in the direction toward one of the poles of our galaxy. Because, that’s where there are fewer stars, and beyond the Milky Way’s stars, there is intergalactic space.

    As a matter of fact, you might say we’re looking out the south window of the galaxy.

    Fomalhaut is the brightest star in the constellation Piscis Austrinus the Southern Fish.

    Beware, though. The other bright “star” in the area in 2024 is the planet Saturn. However, Saturn will be a creamy golden color and shining with a steady light.

    For more sky events, visit EarthSky’s night sky guide.

    To see a precise view from your location, try Stellarium Online.

    Saturn and Fomalhaut in the November evening sky.
    Saturn and the bright star Fomalhaut are the only 2 bright objects in that area of the sky. Chart via EarthSky.

    The Milky Way’s south galactic pole

    Sky chart showing 6 constellations. Constellation Sculptor (triangle shape) is in the middle, and the South Galactic Pole (circle with tick marks) is at the top left of Sculptor.
    The circle with tick marks indicates the position of the south galactic pole, just above the triangle shape of Sculptor. Chart via EarthSky.

    Why to find Fomalhaut? When you look at this star – sometimes called the Loneliest Star – you are looking some 90 degrees from the plane of our galaxy’s equator.

    Our Milky Way galaxy is round and flat, like a pancake. When you look toward Fomalhaut, you’re looking away from the pancake, and out the south window of the galaxy. In other words, we’re looking away from the star-packed disk of the galaxy, into intergalactic space and the realm of galaxies.

    Want the exact location of the south galactic pole? It lies east of Fomalhaut, in the faint constellation Sculptor. See the chart above.

    Finding Fomalhaut

    Fomalhaut is a very noticeable star because it’s in a region of the heavens where there are few stars bright enough to be seen with the eye. That’s why Fomalhaut is often said to be the loneliest star. If you’re not sure, try using the Great Square of Pegasus to confirm the star you see is Fomalhaut. See the chart below. By the way, in 2024, Saturn will lie between the Great Square and Fomalhaut.

    Our galaxy’s south window from the Northern Hemisphere:

    The Great Square of Pegasus appears high in the south to overhead by around 7 to 8 p.m. local time in late November and early December. This large asterism really does look like a large square pattern, with four medium-bright stars marking the corners. Draw a line through the Great Square’s two westernmost (or right-hand) stars, and extend that line southward to land on Fomalhaut.

    From the Southern Hemisphere:

    The Great Square of Pegasus appears low in the northern sky. Then draw a line from the two westernmost stars upward to Fomalhaut. So, just take the chart below, and turn it upside-down!

    hart showing Great Square of Pegasus (at the top of the chart) in relationship to Fomalhaut (bottom right) and Sculptor (bottom left).
    The 4 stars making up the Great Square of Pegasus. You can use the Great Square to find the star Fomalhaut. Chart via EarthSky.

    Bottom line: Use the Great Square of Pegasus to locate Fomalhaut. And once you’ve found Fomalhaut, you’re on your way to looking out our galaxy’s south window into intergalactic space.

    Easily locate stars and constellations during any day and time with EarthSky’s Planisphere.

    The post Galaxy’s south window looks into intergalactic space first appeared on EarthSky.



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