September guide to the bright planets

View larger. | Our friend Duke Marsh wrote on August 23, 2018: “Four of the five bright planets joined the moon above the riverfront in New Albany, Indiana. Each planet can be see directly below its name at the top. Looks best viewed full-screen on a computer monitor or large tablet.” These worlds will continue to light up the sky at nightfall throughout September, 2018.

Click the name of a planet to learn more about its visibility in September 2018: Venus, Jupiter, Saturn, Mars and Mercury

Circle September 11, 12 and 13 on your calendar, for that’s when the waxing crescent moon goses by Venus and Jupiter. Read more.

Venus is the brightest planet, and – as seen from around the world -lights up in the southwestern or western sky after sunset, and is nearly impossible to miss as the evening “star” – unless you reside at a far northerly outpost, such as Alaska or Scandinavia. That far north, Venus sets very soon after sunset.

Although Venus always ranks as the 3rd-brightest celestial object after the sun and moon, it outdoes itself in September 2018. Look for this dazzling world to shine at its brilliant best in the evening sky around the time of the September equinox.

Read more: Venus at greatest illuminated extent on September 21

At mid-northern latitudes, Venus sets roughly 1 1/2 hours after the sun in early September. By the month’s end, that’ll taper to about an hour after sunset.

What’s interesting is that – as seen from mid-northern latitudes – Venus reached its highest altitude in the evening sky after sunset in June 2018. And yet Venus’ greatest elongation (greatest apparent distance from the setting sun) happened last month, on August 17.

Why? It’s because of the shifting angle of the ecliptic, which marks the annual path of the sun, and the approximate path of the moon and planets across our sky. From our northerly latitudes, the ecliptic falls closer to the horizon and makes an increasingly shallower angle with the sunset horizon as we approach the September autumn equinox. That keeps Venus low in the sky at northerly latitudes.

Venus, the moon – and see the moon’s reflection in Lisbon, Portugal on August 13, 2018. Photo by Henrique Feliciano Silva,

The Southern Hemisphere has the big advantage in seeing Venus because September is a late winter/early spring month in that part of the world. Therefore, day by day, the ecliptic climbs higher in the sky and intersects the sunset horizon at an increasingly steeper angle as the Southern Hemisphere approaches their September spring equinox. That places Venus high above the setting sun (rather than to the side of it as for us northerners). At temperate latitudes in the Southern Hemisphere (South Africa, southern Australia), Venus sets about 3 1/2 hours after sunset in early September and 2 1/2 hours after the sun at the month’s end.

In short, when it comes to the height of the ecliptic in the evening sky, remember the saying “spring up and fall down.” At sunset on the spring equinox, the ecliptic soars highest up for the year. At sunset on the autumn equinox, the ecliptic falls lowest down. That applies to both the Northern and Southern Hemispheres.

Circle September 11, 12 and 13 on your calendar. That’s when the young moon will be sweeping past Venus (and Jupiter) in the evening sky. The western twilight will make the pairing all the more picturesque.

From the Southern Hemisphere, look for Venus to adorn the evening sky from now till nearly the end of October 2018. At middle latitudes in the Northern Hemisphere, it’ll take a diligent effort to catch Venus after sunset in late September and early October 2018.

Watch for the moon to move by the planet Jupiter and the star Antares from September 13 to 15, 2018. Read more.

Jupiter remains bright and beautiful throughout September 2018. Its opposition took place on May 8-9, 2018, and ever since, the planet has been shifting westward, or in the direction of sunset. Around the world, you’ll find Jupiter highest up for the night around dusk or nightfall, appearing rather low in the southwest sky at northerly latitudes; in the Southern Hemisphere, you’ll see Jupiter quite high in the western sky.

Jupiter is brighter than any star, but it’s not brighter than Venus, which beams mightily in the west or southwest after sunset. This month, Jupiter reclaims its spot as the 4th-brightest celestial object, after the sun, moon and Venus. For some two months, from about July 7 to September 7, Mars supplanted Jupiter as the brighter of these two heavenly bodies.

Once again, as with Venus, Jupiter stays out longer after sunset in the Southern Hemisphere. That’s because the ecliptic (pathway of the sun, moon and planets) hits the evening horizon almost straight up and down in the Southern Hemisphere, yet at a shallow angle in the Northern Hemisphere.

For instance, at mid-northern latitudes (United States, mainland Europe, Japan), Jupiter sets about 3 hours after the sun in early September and about 2 hours after at the month’s end.

In contrast, at temperate latitudes in the Southern Hemisphere (Cape Town, South Africa, and southern Australia), Jupiter sets about 5 hours after the sun in early September and about 3 1/2 hours after by the month’s end.

Jupiter shines in front of the constellation Libra the Scales until November 2018. Look for Libra’s brightest stars near Jupiter, Zubenelgenubi and Zubeneschamali (both star names are pronounced with the same rhythm as Obi-Wan Kenobi of “Star Wars”).

If you aim binoculars at Zubenelgenubi, you’ll see this star as two stars. Zubeneschamali, meanwhile, is said to appear green in color, although, astronomers say, stars can’t look green.

Let the moon guide your eye to Jupiter for several evenings, centered on or around September 13.

Watch for the moon to sweep by the planets Saturn and Mars from September 17 to 19. Read more.

Saturn and Mars are ideally placed for viewing around nightfall. Around the world in September, Saturn transits – reaches its highest point in the sky – around dusk or nightfall. Then Mars transits roughly two hours after Saturn does.

Click here for a recommended sky almanac providing you with the transit times for the planets.

From mid-northern latitudes, Saturn stays out until around midnight (1 a.m. daylight saving time) in early September. By the month’s end, Saturn will set around 10 p.m. (11 p.m. daylight saving time). Mars will follow Saturn beneath the western horizon roughly two hours after Saturn does.

From temperate latitudes in the Southern Hemisphere, Saturn and Mars both stay out until well after midnight.

You can tell Mars from Saturn because Mars has a reddish color and Saturn looks golden. Binoculars show their colors better than the eye alone.

Watch for the moon to pair up with Saturn on or near September 17 and with Mars on or near September 19.

At present, both Saturn and Mars shine more brilliantly than a 1st-magnitude star. However, Mars is brighter than Saturn. Saturn’s brilliance peaked at its June 27 opposition, and Mars’ brilliance came to a head at its July 27 opposition.

It’s not often that Mars outshines Jupiter, normally the fourth-brightest celestial object to light up the sky, after the sun, moon and Venus. But, for a couple of months in 2018, Mars outshines Jupiter from about July 7 to September 7, 2018.

Both Mars and Saturn are slowly dimming throughout the month. Because Mars is dimming at a faster rate than Saturn is, Mars will be nearly 10 times brighter than Saturn at the beginning of the month, and some 5 times brighter by the month’s end.

Remember Mars’ historically close opposition of August 28, 2003? That year, it was closer and brighter than it had been in some 60,000 years. The July opposition was the best since 2003, and what’s more, Mars will remain bright and beautiful all through August 2018!

Read more: Mars brighter in 2018 than since 2003

Click here for more about close and far Mars oppositions

Diagram by Roy L. Bishop. Copyright Royal Astronomical Society of Canada. Used with permission. Visit the RASC estore to purchase the Observer’s Handbook, a necessary tool for all skywatchers. Read more about this image.

Mercury, the innermost planet of the solar system, might still be visible before sunrise from the Northern Hemisphere and the southern tropics in early September. But this world is rapidly falling into glare of sunrise throughout the month, and its reign as the morning “star” will officially end on September 21, 2018 (same date that Venus reaches its greatest illuminated extent in the evening sky).

In the last week of August 2018, Mercury formed an equilateral triangle with the bright stars Pollux and Procyon. In the first week of September, Mercury will be farther away from Pollux and Procyon on the sky’s dome, making an isosceles triangle instead.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Bottom line: In September 2018, four planets arc across the sky at dusk and nightfall. Venus lights up the western sky, with Jupiter shining above Venus. Mars and Saturn light up the southern sky at nightfall from northerly latitudes. From the Southern Hemisphere, Mars and Saturn shine high overhead. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

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View larger. | Our friend Duke Marsh wrote on August 23, 2018: “Four of the five bright planets joined the moon above the riverfront in New Albany, Indiana. Each planet can be see directly below its name at the top. Looks best viewed full-screen on a computer monitor or large tablet.” These worlds will continue to light up the sky at nightfall throughout September, 2018.

Click the name of a planet to learn more about its visibility in September 2018: Venus, Jupiter, Saturn, Mars and Mercury

Circle September 11, 12 and 13 on your calendar, for that’s when the waxing crescent moon goses by Venus and Jupiter. Read more.

Venus is the brightest planet, and – as seen from around the world -lights up in the southwestern or western sky after sunset, and is nearly impossible to miss as the evening “star” – unless you reside at a far northerly outpost, such as Alaska or Scandinavia. That far north, Venus sets very soon after sunset.

Although Venus always ranks as the 3rd-brightest celestial object after the sun and moon, it outdoes itself in September 2018. Look for this dazzling world to shine at its brilliant best in the evening sky around the time of the September equinox.

Read more: Venus at greatest illuminated extent on September 21

At mid-northern latitudes, Venus sets roughly 1 1/2 hours after the sun in early September. By the month’s end, that’ll taper to about an hour after sunset.

What’s interesting is that – as seen from mid-northern latitudes – Venus reached its highest altitude in the evening sky after sunset in June 2018. And yet Venus’ greatest elongation (greatest apparent distance from the setting sun) happened last month, on August 17.

Why? It’s because of the shifting angle of the ecliptic, which marks the annual path of the sun, and the approximate path of the moon and planets across our sky. From our northerly latitudes, the ecliptic falls closer to the horizon and makes an increasingly shallower angle with the sunset horizon as we approach the September autumn equinox. That keeps Venus low in the sky at northerly latitudes.

Venus, the moon – and see the moon’s reflection in Lisbon, Portugal on August 13, 2018. Photo by Henrique Feliciano Silva,

The Southern Hemisphere has the big advantage in seeing Venus because September is a late winter/early spring month in that part of the world. Therefore, day by day, the ecliptic climbs higher in the sky and intersects the sunset horizon at an increasingly steeper angle as the Southern Hemisphere approaches their September spring equinox. That places Venus high above the setting sun (rather than to the side of it as for us northerners). At temperate latitudes in the Southern Hemisphere (South Africa, southern Australia), Venus sets about 3 1/2 hours after sunset in early September and 2 1/2 hours after the sun at the month’s end.

In short, when it comes to the height of the ecliptic in the evening sky, remember the saying “spring up and fall down.” At sunset on the spring equinox, the ecliptic soars highest up for the year. At sunset on the autumn equinox, the ecliptic falls lowest down. That applies to both the Northern and Southern Hemispheres.

Circle September 11, 12 and 13 on your calendar. That’s when the young moon will be sweeping past Venus (and Jupiter) in the evening sky. The western twilight will make the pairing all the more picturesque.

From the Southern Hemisphere, look for Venus to adorn the evening sky from now till nearly the end of October 2018. At middle latitudes in the Northern Hemisphere, it’ll take a diligent effort to catch Venus after sunset in late September and early October 2018.

Watch for the moon to move by the planet Jupiter and the star Antares from September 13 to 15, 2018. Read more.

Jupiter remains bright and beautiful throughout September 2018. Its opposition took place on May 8-9, 2018, and ever since, the planet has been shifting westward, or in the direction of sunset. Around the world, you’ll find Jupiter highest up for the night around dusk or nightfall, appearing rather low in the southwest sky at northerly latitudes; in the Southern Hemisphere, you’ll see Jupiter quite high in the western sky.

Jupiter is brighter than any star, but it’s not brighter than Venus, which beams mightily in the west or southwest after sunset. This month, Jupiter reclaims its spot as the 4th-brightest celestial object, after the sun, moon and Venus. For some two months, from about July 7 to September 7, Mars supplanted Jupiter as the brighter of these two heavenly bodies.

Once again, as with Venus, Jupiter stays out longer after sunset in the Southern Hemisphere. That’s because the ecliptic (pathway of the sun, moon and planets) hits the evening horizon almost straight up and down in the Southern Hemisphere, yet at a shallow angle in the Northern Hemisphere.

For instance, at mid-northern latitudes (United States, mainland Europe, Japan), Jupiter sets about 3 hours after the sun in early September and about 2 hours after at the month’s end.

In contrast, at temperate latitudes in the Southern Hemisphere (Cape Town, South Africa, and southern Australia), Jupiter sets about 5 hours after the sun in early September and about 3 1/2 hours after by the month’s end.

Jupiter shines in front of the constellation Libra the Scales until November 2018. Look for Libra’s brightest stars near Jupiter, Zubenelgenubi and Zubeneschamali (both star names are pronounced with the same rhythm as Obi-Wan Kenobi of “Star Wars”).

If you aim binoculars at Zubenelgenubi, you’ll see this star as two stars. Zubeneschamali, meanwhile, is said to appear green in color, although, astronomers say, stars can’t look green.

Let the moon guide your eye to Jupiter for several evenings, centered on or around September 13.

Watch for the moon to sweep by the planets Saturn and Mars from September 17 to 19. Read more.

Saturn and Mars are ideally placed for viewing around nightfall. Around the world in September, Saturn transits – reaches its highest point in the sky – around dusk or nightfall. Then Mars transits roughly two hours after Saturn does.

Click here for a recommended sky almanac providing you with the transit times for the planets.

From mid-northern latitudes, Saturn stays out until around midnight (1 a.m. daylight saving time) in early September. By the month’s end, Saturn will set around 10 p.m. (11 p.m. daylight saving time). Mars will follow Saturn beneath the western horizon roughly two hours after Saturn does.

From temperate latitudes in the Southern Hemisphere, Saturn and Mars both stay out until well after midnight.

You can tell Mars from Saturn because Mars has a reddish color and Saturn looks golden. Binoculars show their colors better than the eye alone.

Watch for the moon to pair up with Saturn on or near September 17 and with Mars on or near September 19.

At present, both Saturn and Mars shine more brilliantly than a 1st-magnitude star. However, Mars is brighter than Saturn. Saturn’s brilliance peaked at its June 27 opposition, and Mars’ brilliance came to a head at its July 27 opposition.

It’s not often that Mars outshines Jupiter, normally the fourth-brightest celestial object to light up the sky, after the sun, moon and Venus. But, for a couple of months in 2018, Mars outshines Jupiter from about July 7 to September 7, 2018.

Both Mars and Saturn are slowly dimming throughout the month. Because Mars is dimming at a faster rate than Saturn is, Mars will be nearly 10 times brighter than Saturn at the beginning of the month, and some 5 times brighter by the month’s end.

Remember Mars’ historically close opposition of August 28, 2003? That year, it was closer and brighter than it had been in some 60,000 years. The July opposition was the best since 2003, and what’s more, Mars will remain bright and beautiful all through August 2018!

Read more: Mars brighter in 2018 than since 2003

Click here for more about close and far Mars oppositions

Diagram by Roy L. Bishop. Copyright Royal Astronomical Society of Canada. Used with permission. Visit the RASC estore to purchase the Observer’s Handbook, a necessary tool for all skywatchers. Read more about this image.

Mercury, the innermost planet of the solar system, might still be visible before sunrise from the Northern Hemisphere and the southern tropics in early September. But this world is rapidly falling into glare of sunrise throughout the month, and its reign as the morning “star” will officially end on September 21, 2018 (same date that Venus reaches its greatest illuminated extent in the evening sky).

In the last week of August 2018, Mercury formed an equilateral triangle with the bright stars Pollux and Procyon. In the first week of September, Mercury will be farther away from Pollux and Procyon on the sky’s dome, making an isosceles triangle instead.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Bottom line: In September 2018, four planets arc across the sky at dusk and nightfall. Venus lights up the western sky, with Jupiter shining above Venus. Mars and Saturn light up the southern sky at nightfall from northerly latitudes. From the Southern Hemisphere, Mars and Saturn shine high overhead. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

Don’t miss anything. Subscribe to EarthSky News by email

Get your EarthSky 2018 lunar calendar now, while they last.

Visit EarthSky’s Best Places to Stargaze, and recommend a place we can all enjoy.

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Beluga whales and narwhals go through menopause

A trio of beluga whales. Image via AQUAS Aquarium in Japan.

Although most humans with ovaries go through menopause – marking the end of the child-bearing years – most animals do not. Almost all animals continue reproducing throughout their lives. Now a new study has found two more species – beluga whales and narwhals – that do go through menopause, bringing the total number of known menopausal species to five. Besides humans, the rest are toothed whales, including belugas, narwhals, killer whales (which are actually in the dolphin family) and short-finned pilot whales.

Scientists have long been puzzled about why these few species have evolved in such a way as to stop reproducing, partway through life. Sam Ellis, of the University of Exeter, is lead author of the new study, published August 27, 2018 in the peer-reviewed journal Scientific Reports. Ellis said in a statement:

For menopause to make sense in evolutionary terms, a species needs both a reason to stop reproducing and a reason to live on afterwards.

In killer whales, the reason to stop comes because both male and female offspring stay with their mothers for life – so as a female ages, her group contains more and more of her children and grandchildren.

This increasing relatedness means that, if she keeps having young, they compete with her own direct descendants for resources such as food.

The reason to continue living is that older females are of great benefit to their offspring and grand-offspring. For example, their knowledge of where to find food helps groups survive.

Orcas – killer whales – stay with their mothers for life. Photo via Robert Pitman/UK.Whales.

Menopause in killer whales is well-documented by more than 40 years of study. But because scientists don’t have such detailed information on the lives of belugas and narwhals, the new study used data on dead whales from 16 species The study found dormant ovaries in older beluga and narwhal females.

The findings, said the researchers, suggest belugas and narwhals have social structures which – as with killer whales – mean females find themselves living among more and more close relatives as they age. According to a statement from University of Exeter:

Research on ancestral humans suggests this was also the case for our ancestors. This, combined with the benefits of “late-life helping” – where older females benefit the social group but do not reproduce – may explain why menopause has evolved.

Narwhal. Image via turbosquid.com.

Bottom line: A new study has found that beluga whales and narwhals go through menopause, bringing the total of animals known to experience menopause to five.

Read more from University of Exeter

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A trio of beluga whales. Image via AQUAS Aquarium in Japan.

Although most humans with ovaries go through menopause – marking the end of the child-bearing years – most animals do not. Almost all animals continue reproducing throughout their lives. Now a new study has found two more species – beluga whales and narwhals – that do go through menopause, bringing the total number of known menopausal species to five. Besides humans, the rest are toothed whales, including belugas, narwhals, killer whales (which are actually in the dolphin family) and short-finned pilot whales.

Scientists have long been puzzled about why these few species have evolved in such a way as to stop reproducing, partway through life. Sam Ellis, of the University of Exeter, is lead author of the new study, published August 27, 2018 in the peer-reviewed journal Scientific Reports. Ellis said in a statement:

For menopause to make sense in evolutionary terms, a species needs both a reason to stop reproducing and a reason to live on afterwards.

In killer whales, the reason to stop comes because both male and female offspring stay with their mothers for life – so as a female ages, her group contains more and more of her children and grandchildren.

This increasing relatedness means that, if she keeps having young, they compete with her own direct descendants for resources such as food.

The reason to continue living is that older females are of great benefit to their offspring and grand-offspring. For example, their knowledge of where to find food helps groups survive.

Orcas – killer whales – stay with their mothers for life. Photo via Robert Pitman/UK.Whales.

Menopause in killer whales is well-documented by more than 40 years of study. But because scientists don’t have such detailed information on the lives of belugas and narwhals, the new study used data on dead whales from 16 species The study found dormant ovaries in older beluga and narwhal females.

The findings, said the researchers, suggest belugas and narwhals have social structures which – as with killer whales – mean females find themselves living among more and more close relatives as they age. According to a statement from University of Exeter:

Research on ancestral humans suggests this was also the case for our ancestors. This, combined with the benefits of “late-life helping” – where older females benefit the social group but do not reproduce – may explain why menopause has evolved.

Narwhal. Image via turbosquid.com.

Bottom line: A new study has found that beluga whales and narwhals go through menopause, bringing the total of animals known to experience menopause to five.

Read more from University of Exeter

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Saturn and its rings

View larger. | Photo by Tom Wildoner at the Dark Side Observatory, Weatherly, Pennsylvania. August 28, 2018. Sky-Watcher Esprit 120mmED Triplet Refractor, Celestron CGEM-DX mount, ASI 290MC, and Televue 2.5x Powermate (1.25”). Captured with SharpCap software (best 25% of 30k frames) and processed in Corel Paintshop Pro. Thank you, Tom!

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View larger. | Photo by Tom Wildoner at the Dark Side Observatory, Weatherly, Pennsylvania. August 28, 2018. Sky-Watcher Esprit 120mmED Triplet Refractor, Celestron CGEM-DX mount, ASI 290MC, and Televue 2.5x Powermate (1.25”). Captured with SharpCap software (best 25% of 30k frames) and processed in Corel Paintshop Pro. Thank you, Tom!

from EarthSky https://ift.tt/2C17qPZ

Andromeda galaxy, the nearest large spiral

View larger. | The Andromeda Galaxy with 2 of its satellite galaxies, via Flickr user Adam Evans.

Although several dozen minor galaxies lie closer to our Milky Way, the Andromeda galaxy is the closest large spiral galaxy to ours. Excluding the Large and Small Magellanic Clouds, which can’t be seen from northerly latitudes, the Andromeda galaxy – also known as M31 – is the brightest galaxy you can see. At 2.5 million light-years, it’s also the most distant thing visible to your unaided eye.

To the eye, this galaxy appears as a smudge of light larger than a full moon.

Josh Blash captured this image of the Andromeda galaxy. It’s big, bigger than a full moon. If you know approximately where to look for this hazy smudge in your night sky – and your sky is very dark – you might pick out the galaxy just by looking for it.

When to look for the Andromeda Galaxy. From mid-northern latitudes, you can see M31 – also called the Andromeda galaxy – for at least part of every night, all year long. But most people see the galaxy first around northern autumn, when it’s high enough in the sky to be seen from nightfall until daybreak.

In late August and early September, begin looking for the galaxy in mid-evening, about midway between your local nightfall and midnight.

In late September and early October, the Andromeda galaxy shines in your eastern sky at nightfall, swings high overhead in the middle of the night, and stands rather high in the west at the onset of morning dawn.

Winter evenings are also good for viewing the Andromeda galaxy.

If you are far from city lights, and it’s a moonless night – and you’re looking on a late summer, autumn or winter evening – it’s possible you’ll simply notice the galaxy in your night sky. It’s looks like a hazy patch in the sky, as wide across as a full moon.

But if you look, and don’t see the galaxy – yet you know you’re looking at a time when it’s above the horizon – you can star-hop to find the galaxy in one of two ways. The easiest way is to use the constellation Cassiopeia. You can also use the Great Square of Pegasus.

Most people use the M- or W-shaped constellation Cassiopeia to find the Andromeda galaxy. See how the star Schedar points to the galaxy?

Find the Andromeda galaxy using the constellation Cassiopeia. The constellation Cassiopeia the Queen is one of the easiest constellations to recognize. It’s shaped like the letter M or W. Look generally northward on the sky’s dome to find this constellation. If you can recognize the North Star, Polaris – and if you know how to find the Big Dipper – be aware that the Big Dipper and Cassiopeia move around Polaris like the hands of a clock, always opposite each other.

To find the Andromeda galaxy via Cassiopeia, look for the star Schedar. In the illustration above, see how the star Schedar points to the galaxy?

Most people use the Cassiopeia to find the Andromeda galaxy, because Cassiopeia itself is so easy to spot.

Use the Great Square of Pegasus to find the Andromeda Galaxy. A line between Mirach and Mu Andromedae points to the galaxy.

Find the Andromeda galaxy using the Great Square of Pegasus. Here’s another way to find the galaxy. It’s a longer route, but, in many ways, more beautiful.

You’ll be hopping to the Andromeda galaxy from the Great Square of Pegasus. In autumn, the Great Square of Pegasus looks like a great big baseball diamond in the eastern sky. Envision the bottom star of the Square’s four stars as home plate, then draw an imaginary line from the “first base” star though the “third base” star to locate two streamers of stars flying away from the Great Square. These stars belong to the constellation Andromeda the Princess.

On each streamer, go two stars north (left) of the third base star, locating the stars Mirach and Mu Andromedae. Draw a line from Mirach through Mu Andromedae, going twice the Mirach/Mu Andromedae distance. You’ve just landed on the Andromeda galaxy, which looks like a smudge of light to the unaided eye.

If you can’t see the Andromeda galaxy with the eye alone, by all means use binoculars.

The Great Andromeda Nebula, photographed in the year 1900. At this point, astronomers could not discern individual stars in the galaxy. Many thought it was a cloud of gas within our Milky Way – a place where new stars were forming.Image via Wikimedia Commons.

History of our knowledge of the Andromeda galaxy. At one time, the Andromeda galaxy was called the Great Andromeda Nebula. Astronomers thought this patch of light was composed of glowing gases, or was perhaps a solar system in the process of formation.

It wasn’t until the 20th century that astronomers were able to resolve the Andromeda spiral nebula into individual stars. This discovery lead to a controversy about whether the Andromeda spiral nebula and other spiral nebulae lie within or outside the Milky Way.

In the 1920s Edwin Hubble finally put the matter to rest, when he used Cepheid variable stars within the Andromeda galaxy to determine that it is indeed an island universe residing beyond the bounds of our Milky Way galaxy.

Artist’s illustration of our Local Group via Chandra X-Ray Observatory.

Andromeda and Milky Way in context. The Andromeda galaxy and our Milky Way galaxy reign as the two most massive and dominant galaxies within the Local Group of Galaxies. The Andromeda Galaxy is the largest galaxy of the Local Group, which, in addition to the Milky Way, also contains the Triangulum Galaxy, and about 30 other smaller galaxies.

Both the Milky Way and the Andromeda galaxies lay claim to about a dozen satellite galaxies. Both are some 100,000 light-years across, containing enough mass to make billions of stars.

Astronomers have discovered that our Local Group is on the outskirts of a giant cluster of several thousand galaxies – which astronomers call the Virgo Cluster.

We also know of an irregular supercluster of galaxies, which contains the Virgo Cluster, which in turn contains our Local Group, which in turn contains our Milky Way galaxy and the nearby and Andromeda galaxy. At least 100 galaxy groups and clusters are located within this Virgo Supercluster. Its diameter is thought to be about 110 million light-years.

The Virgo Supercluster is thought to be one of millions of superclusters in the observable universe.

View larger. | View zoomable image. | A portion of the Andromeda galaxy via NASA/ESA.

Bottom line: At 2.5 million light-years, the Great Andromeda galaxy (Messier 31) rates as one of the most distant objects you can see with the unaided eye.

The Andromeda galaxy (M31) is at RA: 0h 42.7m; Dec: 41^o 16′ north

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View larger. | The Andromeda Galaxy with 2 of its satellite galaxies, via Flickr user Adam Evans.

Although several dozen minor galaxies lie closer to our Milky Way, the Andromeda galaxy is the closest large spiral galaxy to ours. Excluding the Large and Small Magellanic Clouds, which can’t be seen from northerly latitudes, the Andromeda galaxy – also known as M31 – is the brightest galaxy you can see. At 2.5 million light-years, it’s also the most distant thing visible to your unaided eye.

To the eye, this galaxy appears as a smudge of light larger than a full moon.

Josh Blash captured this image of the Andromeda galaxy. It’s big, bigger than a full moon. If you know approximately where to look for this hazy smudge in your night sky – and your sky is very dark – you might pick out the galaxy just by looking for it.

When to look for the Andromeda Galaxy. From mid-northern latitudes, you can see M31 – also called the Andromeda galaxy – for at least part of every night, all year long. But most people see the galaxy first around northern autumn, when it’s high enough in the sky to be seen from nightfall until daybreak.

In late August and early September, begin looking for the galaxy in mid-evening, about midway between your local nightfall and midnight.

In late September and early October, the Andromeda galaxy shines in your eastern sky at nightfall, swings high overhead in the middle of the night, and stands rather high in the west at the onset of morning dawn.

Winter evenings are also good for viewing the Andromeda galaxy.

If you are far from city lights, and it’s a moonless night – and you’re looking on a late summer, autumn or winter evening – it’s possible you’ll simply notice the galaxy in your night sky. It’s looks like a hazy patch in the sky, as wide across as a full moon.

But if you look, and don’t see the galaxy – yet you know you’re looking at a time when it’s above the horizon – you can star-hop to find the galaxy in one of two ways. The easiest way is to use the constellation Cassiopeia. You can also use the Great Square of Pegasus.

Most people use the M- or W-shaped constellation Cassiopeia to find the Andromeda galaxy. See how the star Schedar points to the galaxy?

Find the Andromeda galaxy using the constellation Cassiopeia. The constellation Cassiopeia the Queen is one of the easiest constellations to recognize. It’s shaped like the letter M or W. Look generally northward on the sky’s dome to find this constellation. If you can recognize the North Star, Polaris – and if you know how to find the Big Dipper – be aware that the Big Dipper and Cassiopeia move around Polaris like the hands of a clock, always opposite each other.

To find the Andromeda galaxy via Cassiopeia, look for the star Schedar. In the illustration above, see how the star Schedar points to the galaxy?

Most people use the Cassiopeia to find the Andromeda galaxy, because Cassiopeia itself is so easy to spot.

Use the Great Square of Pegasus to find the Andromeda Galaxy. A line between Mirach and Mu Andromedae points to the galaxy.

Find the Andromeda galaxy using the Great Square of Pegasus. Here’s another way to find the galaxy. It’s a longer route, but, in many ways, more beautiful.

You’ll be hopping to the Andromeda galaxy from the Great Square of Pegasus. In autumn, the Great Square of Pegasus looks like a great big baseball diamond in the eastern sky. Envision the bottom star of the Square’s four stars as home plate, then draw an imaginary line from the “first base” star though the “third base” star to locate two streamers of stars flying away from the Great Square. These stars belong to the constellation Andromeda the Princess.

On each streamer, go two stars north (left) of the third base star, locating the stars Mirach and Mu Andromedae. Draw a line from Mirach through Mu Andromedae, going twice the Mirach/Mu Andromedae distance. You’ve just landed on the Andromeda galaxy, which looks like a smudge of light to the unaided eye.

If you can’t see the Andromeda galaxy with the eye alone, by all means use binoculars.

The Great Andromeda Nebula, photographed in the year 1900. At this point, astronomers could not discern individual stars in the galaxy. Many thought it was a cloud of gas within our Milky Way – a place where new stars were forming.Image via Wikimedia Commons.

History of our knowledge of the Andromeda galaxy. At one time, the Andromeda galaxy was called the Great Andromeda Nebula. Astronomers thought this patch of light was composed of glowing gases, or was perhaps a solar system in the process of formation.

It wasn’t until the 20th century that astronomers were able to resolve the Andromeda spiral nebula into individual stars. This discovery lead to a controversy about whether the Andromeda spiral nebula and other spiral nebulae lie within or outside the Milky Way.

In the 1920s Edwin Hubble finally put the matter to rest, when he used Cepheid variable stars within the Andromeda galaxy to determine that it is indeed an island universe residing beyond the bounds of our Milky Way galaxy.

Artist’s illustration of our Local Group via Chandra X-Ray Observatory.

Andromeda and Milky Way in context. The Andromeda galaxy and our Milky Way galaxy reign as the two most massive and dominant galaxies within the Local Group of Galaxies. The Andromeda Galaxy is the largest galaxy of the Local Group, which, in addition to the Milky Way, also contains the Triangulum Galaxy, and about 30 other smaller galaxies.

Both the Milky Way and the Andromeda galaxies lay claim to about a dozen satellite galaxies. Both are some 100,000 light-years across, containing enough mass to make billions of stars.

Astronomers have discovered that our Local Group is on the outskirts of a giant cluster of several thousand galaxies – which astronomers call the Virgo Cluster.

We also know of an irregular supercluster of galaxies, which contains the Virgo Cluster, which in turn contains our Local Group, which in turn contains our Milky Way galaxy and the nearby and Andromeda galaxy. At least 100 galaxy groups and clusters are located within this Virgo Supercluster. Its diameter is thought to be about 110 million light-years.

The Virgo Supercluster is thought to be one of millions of superclusters in the observable universe.

View larger. | View zoomable image. | A portion of the Andromeda galaxy via NASA/ESA.

Bottom line: At 2.5 million light-years, the Great Andromeda galaxy (Messier 31) rates as one of the most distant objects you can see with the unaided eye.

The Andromeda galaxy (M31) is at RA: 0h 42.7m; Dec: 41^o 16′ north

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Great Square of Pegasus points to Andromeda galaxy

Tonight, look for the nearest large spiral galaxy to our Milky Way. It’s becoming well placed for evening viewing from Northern Hemisphere locations. The Great Square of Pegasus is a great jumping off point for finding the famous Andromeda galaxy, also known to astronomers as Messier 31.

As seen from mid-northern latitudes, the Great Square of Pegasus looks like a … well … a big square. Go figure. The Great Square of Pegasus sparkles over the eastern horizon at about 9 p.m. daylight-saving time in late August and early September. Some two weeks from now – around mid-September – the Great Square will return to the same place in the sky about an hour earlier. By autumn, people at northerly latitudes will see the Great Square of Pegasus at nightfall.

For some idea of the Great Square’s size, extend your hand an arm length from your eye. You’ll see that any two Great Square stars are farther apart than the width of your hand.

Now let’s find the Andromeda galaxy. To get your bearings, locate the Great Square of Pegasus in your eastern sky this evening (or on the chart at the top of this post). But instead of thinking of the Great Square as a square, think of it as a baseball diamond. Now imagine the farthest star to the left – Alpheratz – as the third-base star. A line drawn from the first-base star through Alpheratz points in the general direction of the Andromeda galaxy.

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View larger. | Many people find the Andromeda galaxy from the two streamers of stars extending from the Great Square (they are the constellation Andromeda). Or they find the galaxy via the constellation Cassiopeia. This photo via EarthSky Facebook friend Cattleya Flores Viray.

Now let’s get more specific. If it’s dark enough, you’ll see two streamers of stars flying to the north (or left) of the star Alpheratz on August and September evenings. To me, these two streamers make a pattern much like a bugle or a cornucopia. They are actually another constellation, the constellation Andromeda the Princess. Along the bottom streamer, star-hop from Alpheratz to the star Mirach. Draw a line from Mirach through the upper streamer star – which is called Mu Andromedae – and go about the same distance again as that between Mirach and Mu. You’ve just located the Andromeda galaxy!

View larger. | The Andromeda galaxy (right side of photo) as seen by EarthSky Facebook friend Ted Van at a Montana campsite in mid-August 2012.

What does the Andromeda galaxy look like the eye alone? It looks like a fuzzy patch in a dark sky. If you can’t see this fuzzy patch of light with the unaided eye, maybe your sky isn’t dark enough. Try binoculars! Don’t worry if you miss it tonight, for the Andromeda galaxy will be in the evening sky from now until spring.

The Andromeda galaxy and two satellite galaxies as seen through a powerful telescope. To the eye, the galaxy looks like a fuzzy patch. It’s an island of stars in space, much like our Milky Way. Image via NOAO

Bottom line: The Andromeda galaxy can be seen somewhere in our sky for much of every year. Every August, it’s ascending in the sky during the evening hours. To the eye, it looks like a fuzzy patch.

Help support EarthSky! Visit the EarthSky store for to see the great selection of educational tools and team gear we have to offer.

Mirach: Guide star to three galaxies

Cassiopeia the Queen also points to the Andromeda galaxy

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Tonight, look for the nearest large spiral galaxy to our Milky Way. It’s becoming well placed for evening viewing from Northern Hemisphere locations. The Great Square of Pegasus is a great jumping off point for finding the famous Andromeda galaxy, also known to astronomers as Messier 31.

As seen from mid-northern latitudes, the Great Square of Pegasus looks like a … well … a big square. Go figure. The Great Square of Pegasus sparkles over the eastern horizon at about 9 p.m. daylight-saving time in late August and early September. Some two weeks from now – around mid-September – the Great Square will return to the same place in the sky about an hour earlier. By autumn, people at northerly latitudes will see the Great Square of Pegasus at nightfall.

For some idea of the Great Square’s size, extend your hand an arm length from your eye. You’ll see that any two Great Square stars are farther apart than the width of your hand.

Now let’s find the Andromeda galaxy. To get your bearings, locate the Great Square of Pegasus in your eastern sky this evening (or on the chart at the top of this post). But instead of thinking of the Great Square as a square, think of it as a baseball diamond. Now imagine the farthest star to the left – Alpheratz – as the third-base star. A line drawn from the first-base star through Alpheratz points in the general direction of the Andromeda galaxy.

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View larger. | Many people find the Andromeda galaxy from the two streamers of stars extending from the Great Square (they are the constellation Andromeda). Or they find the galaxy via the constellation Cassiopeia. This photo via EarthSky Facebook friend Cattleya Flores Viray.

Now let’s get more specific. If it’s dark enough, you’ll see two streamers of stars flying to the north (or left) of the star Alpheratz on August and September evenings. To me, these two streamers make a pattern much like a bugle or a cornucopia. They are actually another constellation, the constellation Andromeda the Princess. Along the bottom streamer, star-hop from Alpheratz to the star Mirach. Draw a line from Mirach through the upper streamer star – which is called Mu Andromedae – and go about the same distance again as that between Mirach and Mu. You’ve just located the Andromeda galaxy!

View larger. | The Andromeda galaxy (right side of photo) as seen by EarthSky Facebook friend Ted Van at a Montana campsite in mid-August 2012.

What does the Andromeda galaxy look like the eye alone? It looks like a fuzzy patch in a dark sky. If you can’t see this fuzzy patch of light with the unaided eye, maybe your sky isn’t dark enough. Try binoculars! Don’t worry if you miss it tonight, for the Andromeda galaxy will be in the evening sky from now until spring.

The Andromeda galaxy and two satellite galaxies as seen through a powerful telescope. To the eye, the galaxy looks like a fuzzy patch. It’s an island of stars in space, much like our Milky Way. Image via NOAO

Bottom line: The Andromeda galaxy can be seen somewhere in our sky for much of every year. Every August, it’s ascending in the sky during the evening hours. To the eye, it looks like a fuzzy patch.

Help support EarthSky! Visit the EarthSky store for to see the great selection of educational tools and team gear we have to offer.

Mirach: Guide star to three galaxies

Cassiopeia the Queen also points to the Andromeda galaxy

from EarthSky https://ift.tt/1LddC1R

How tiny metal beads could make chemotherapy more effective for brain tumours

Treatments for brain tumours aren’t good enough. Only around 1 in 7 people will survive their disease for a decade or longer. And those in this small but fortunate fraction may also be left with lifelong reminders of their cancer in the form of side effects from their treatment.

But coming up with better ways to tackle these diseases is fraught with difficulty. This stems from the fact that brain tumours are hard to study in the lab. And their complex biology has held back the progress seen with treatments for other cancers.

For example, aggressive brain tumours, such as glioblastoma, quickly spread throughout the brain. This means surgery often won’t be enough to treat the disease, because the operation can’t remove all the cancer cells. It’s then only a matter of time before these invasive cells seed the tumour’s return, and from there the person’s outlook sadly becomes exceedingly bleak.

So, what’s needed to turn this harrowing situation around? Our scientists are on the case. And they’ve come up with an innovative idea that they believe could be a game changer for these patients.

A masked attacker

One way that doctors try to deal with the rogue tumour cells left behind after surgery is chemotherapy, often with the drug temozolomide. But chemotherapy drugs aren’t specific to cancer cells – they target any cell that’s growing quickly in the body. They can therefore cause serious side effects that limit how much of the drug can be given, and that limits their effectiveness.

Researchers at the Cancer Research UK Edinburgh Centre have come up with an idea to solve this issue – and we gave them one of our Pioneer Awards to get it off the ground.

Blending their complementary scientific skills, neurosurgeon Dr Paul Brennan and chemist Professor Asier Unciti-Broceta are developing a new way to make chemotherapy more targeted, and therefore hopefully more effective.

Their two-pronged approach involves modifying the chemotherapy drug temozolomide and creating a harmless implant to be inserted into the brain. The modified drug and implant eventually work together at the tumour site to essentially become a mini drug-making factory.

They’re tweaking the drug so that it’s inactive when given to the patient. They essentially give it a ‘mask’, which means it can travel around the body without causing any unwanted harm to growing healthy cells that it meets.

That’s until the drug reaches the implant: tiny beads made from the metal palladium. These would be placed inside the brain around the area where the tumour was removed during surgery. When the drug encounters the metal, it gets switched on in the perfect place to potentially kill any cancerous cells that might be left in the brain.

To find out more, we visited the team in Edinburgh. Watch the video below to see what they’ve been up to.

Beyond brains

By creating a localised attack, the scientists hope that side effects from the chemotherapy will be greatly reduced. That means more chemotherapy could be given, and hopefully that could mean a longer life for the patient.

It’s early days and this approach is still being developed in the lab, so it could be some time before reaching patients. But the results from cancer cells in Petri dishes so far have been encouraging, and the scientists now have their sights set further than brain tumours. Radioactive implants are sometimes used for prostate cancer, for example, so they’ve already started research in mice to explore its potential for this disease too.

While there’s still much to be done, hopefully one day this bright idea will become something meaningful for patients.

Justine

from Cancer Research UK – Science blog https://ift.tt/2BYCv6N

Treatments for brain tumours aren’t good enough. Only around 1 in 7 people will survive their disease for a decade or longer. And those in this small but fortunate fraction may also be left with lifelong reminders of their cancer in the form of side effects from their treatment.

But coming up with better ways to tackle these diseases is fraught with difficulty. This stems from the fact that brain tumours are hard to study in the lab. And their complex biology has held back the progress seen with treatments for other cancers.

For example, aggressive brain tumours, such as glioblastoma, quickly spread throughout the brain. This means surgery often won’t be enough to treat the disease, because the operation can’t remove all the cancer cells. It’s then only a matter of time before these invasive cells seed the tumour’s return, and from there the person’s outlook sadly becomes exceedingly bleak.

So, what’s needed to turn this harrowing situation around? Our scientists are on the case. And they’ve come up with an innovative idea that they believe could be a game changer for these patients.

A masked attacker

One way that doctors try to deal with the rogue tumour cells left behind after surgery is chemotherapy, often with the drug temozolomide. But chemotherapy drugs aren’t specific to cancer cells – they target any cell that’s growing quickly in the body. They can therefore cause serious side effects that limit how much of the drug can be given, and that limits their effectiveness.

Researchers at the Cancer Research UK Edinburgh Centre have come up with an idea to solve this issue – and we gave them one of our Pioneer Awards to get it off the ground.

Blending their complementary scientific skills, neurosurgeon Dr Paul Brennan and chemist Professor Asier Unciti-Broceta are developing a new way to make chemotherapy more targeted, and therefore hopefully more effective.

Their two-pronged approach involves modifying the chemotherapy drug temozolomide and creating a harmless implant to be inserted into the brain. The modified drug and implant eventually work together at the tumour site to essentially become a mini drug-making factory.

They’re tweaking the drug so that it’s inactive when given to the patient. They essentially give it a ‘mask’, which means it can travel around the body without causing any unwanted harm to growing healthy cells that it meets.

That’s until the drug reaches the implant: tiny beads made from the metal palladium. These would be placed inside the brain around the area where the tumour was removed during surgery. When the drug encounters the metal, it gets switched on in the perfect place to potentially kill any cancerous cells that might be left in the brain.

To find out more, we visited the team in Edinburgh. Watch the video below to see what they’ve been up to.

Beyond brains

By creating a localised attack, the scientists hope that side effects from the chemotherapy will be greatly reduced. That means more chemotherapy could be given, and hopefully that could mean a longer life for the patient.

It’s early days and this approach is still being developed in the lab, so it could be some time before reaching patients. But the results from cancer cells in Petri dishes so far have been encouraging, and the scientists now have their sights set further than brain tumours. Radioactive implants are sometimes used for prostate cancer, for example, so they’ve already started research in mice to explore its potential for this disease too.

While there’s still much to be done, hopefully one day this bright idea will become something meaningful for patients.

Justine

from Cancer Research UK – Science blog https://ift.tt/2BYCv6N

New Horizons has Ultima Thule in view

There are 2 highly processed images here, acquired by New Horizons on August 16, 2018. At left, a composite, produced by adding together 48 different exposures, each with an exposure time of 29.967 seconds. The predicted position of the Kuiper Belt object nicknamed Ultima Thule is indicated by the yellow crosshairs. At right, a magnified view of the region in the yellow box, after subtraction of background stars. There it is! Image via NASA/ Johns Hopkins University/ Southwest Research Institute.

The New Horizons spacecraft will remain forever in our hearts as the craft that provided our first glimpses of tiny Pluto and its system of moons, in 2015. Now New Horizons is headed toward its next target, a Kuiper Belt Object (KBO) called 2014 MU69, nicknamed Ultima Thule. New Horizons is moving fast. But space is vast, and distances in the outer solar system are great. So the New Horizons team was reassured earlier this month when the craft returned its first images of Ultima, showing the little KBO is very close to where scientists predicted it would be.

That’s good! It means New Horizons is being targeted in the right direction.

And so New Horizons will continue on its course toward this object, due to make its closest encounter on New Year’s Day, 2019.

Just how fast is New Horizons, by the way? At its launch on January 19, 2006, it was said to be the fastest spacecraft ever to leave Earth orbit. Since then, other craft have been determined to be faster. For example, the Parker Solar Probe, which launched earlier this month (August 12, 2018) is faster. Still, New Horizons is very fast, about 100 times faster than an earthly jet The tweet below, from 2015, is a great illustration.

Flying at 37k feet, this is what it would be like to look out the window of a 747 vs. an SR-71 vs. a New Horizons. pic.twitter.com/ChVsgK77Rl

— Clay Bavor (@claybavor) July 17, 2015

And now New Horizons has its first images of its next target, Ultima Thule, an object that had not been discovered yet when this craft was launched. The set of 48 images were transmitted home through NASA’s Deep Space Network.

NASA said the New Horizons team was thrilled – if not a little surprised – that New Horizons’ telescopic Long Range Reconnaissance Imager (LORRI) was able to see the small, dim object while still more than 100 million miles (160 million km) away, and against a dense background of stars. Hal Weaver, New Horizons project scientist, said in a statement:

The image field is extremely rich with background stars, which makes it difficult to detect faint objects. It really is like finding a needle in a haystack. In these first images, Ultima appears only as a bump on the side of a background star that’s roughly 17 times brighter, but Ultima will be getting brighter – and easier to see – as the spacecraft gets closer.

This first detection is important, NASA said, because the observations New Horizons makes of Ultima over the next four months will help the mission team refine the spacecraft’s course toward a closest approach to Ultima, at 12:33 a.m. EST on January 1, 2019.

The Ultima flyby will be the first-ever close-up exploration of a small Kuiper Belt object and the farthest exploration of any planetary body in history.

Ultima is clearly detected in this image, very close to where scientists predicted, indicating to the team that New Horizons is being targeted in the right direction. At the time of this observation, Ultima Thule was 107 million miles (172 million km) from the New Horizons spacecraft and 4 billion miles (6.5 billion km) from our sun. Image via NASA/ Johns Hopkins University/ Southwest Research Institute.

Bottom line: The New Horizons spacecraft acquired its first images of its next target – the Kuiper Belt Object called 2014 MU69, nicknamed Ultima Thule – on August 16, 2018.

Via Johns Hopkins University

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There are 2 highly processed images here, acquired by New Horizons on August 16, 2018. At left, a composite, produced by adding together 48 different exposures, each with an exposure time of 29.967 seconds. The predicted position of the Kuiper Belt object nicknamed Ultima Thule is indicated by the yellow crosshairs. At right, a magnified view of the region in the yellow box, after subtraction of background stars. There it is! Image via NASA/ Johns Hopkins University/ Southwest Research Institute.

The New Horizons spacecraft will remain forever in our hearts as the craft that provided our first glimpses of tiny Pluto and its system of moons, in 2015. Now New Horizons is headed toward its next target, a Kuiper Belt Object (KBO) called 2014 MU69, nicknamed Ultima Thule. New Horizons is moving fast. But space is vast, and distances in the outer solar system are great. So the New Horizons team was reassured earlier this month when the craft returned its first images of Ultima, showing the little KBO is very close to where scientists predicted it would be.

That’s good! It means New Horizons is being targeted in the right direction.

And so New Horizons will continue on its course toward this object, due to make its closest encounter on New Year’s Day, 2019.

Just how fast is New Horizons, by the way? At its launch on January 19, 2006, it was said to be the fastest spacecraft ever to leave Earth orbit. Since then, other craft have been determined to be faster. For example, the Parker Solar Probe, which launched earlier this month (August 12, 2018) is faster. Still, New Horizons is very fast, about 100 times faster than an earthly jet The tweet below, from 2015, is a great illustration.

Flying at 37k feet, this is what it would be like to look out the window of a 747 vs. an SR-71 vs. a New Horizons. pic.twitter.com/ChVsgK77Rl

— Clay Bavor (@claybavor) July 17, 2015

And now New Horizons has its first images of its next target, Ultima Thule, an object that had not been discovered yet when this craft was launched. The set of 48 images were transmitted home through NASA’s Deep Space Network.

NASA said the New Horizons team was thrilled – if not a little surprised – that New Horizons’ telescopic Long Range Reconnaissance Imager (LORRI) was able to see the small, dim object while still more than 100 million miles (160 million km) away, and against a dense background of stars. Hal Weaver, New Horizons project scientist, said in a statement:

The image field is extremely rich with background stars, which makes it difficult to detect faint objects. It really is like finding a needle in a haystack. In these first images, Ultima appears only as a bump on the side of a background star that’s roughly 17 times brighter, but Ultima will be getting brighter – and easier to see – as the spacecraft gets closer.

This first detection is important, NASA said, because the observations New Horizons makes of Ultima over the next four months will help the mission team refine the spacecraft’s course toward a closest approach to Ultima, at 12:33 a.m. EST on January 1, 2019.

The Ultima flyby will be the first-ever close-up exploration of a small Kuiper Belt object and the farthest exploration of any planetary body in history.

Ultima is clearly detected in this image, very close to where scientists predicted, indicating to the team that New Horizons is being targeted in the right direction. At the time of this observation, Ultima Thule was 107 million miles (172 million km) from the New Horizons spacecraft and 4 billion miles (6.5 billion km) from our sun. Image via NASA/ Johns Hopkins University/ Southwest Research Institute.

Bottom line: The New Horizons spacecraft acquired its first images of its next target – the Kuiper Belt Object called 2014 MU69, nicknamed Ultima Thule – on August 16, 2018.

Via Johns Hopkins University

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