Draconid meteor shower 2021 will peak October 8


Star chart with set of radial arrows at one end of constellation Draco.
Watch for the short-lived Draconid meteor shower at nightfall and early evening on October 8, 2021. This chart faces northward at nightfall in October. The Big Dipper sits low in the northwest. From the southern U.S. and comparable latitudes, in October, obstructions on your northern horizon might hide the Big Dipper from view. From farther south — say, the Southern Hemisphere — you won’t see the Dipper at all in the evening at this time of year. However, if you can spot it low in the sky, use the Big Dipper to star-hop to the star Polaris. Polaris marks the end star in the handle of the Little Dipper. Got all these stars? Then you should also be able to spot Eltanin and Rastaban, the Draconids’ radiant point, high in the northwest sky at nightfall in early October. Draconid meteors radiate from near these stars, which are known as the Dragon’s Eyes.

Draconid meteor shower 2021

Unlike many meteor showers, the Draconids are short-lived. In 2021, watch these meteors at nightfall and early evening on October 8. You might catch some on the nights before and after, as well. Fortunately, the thin waxing crescent moon sets before nightfall and won’t hinder this year’s Draconid shower. The radiant point for the Draconid meteor shower almost coincides with the head of the constellation Draco the Dragon in the northern sky. That’s why the Draconids are best viewed from the Northern Hemisphere. The Draconid shower is a real oddity, in that the radiant point stands highest in the sky as darkness falls. That means that, unlike many meteor showers, more Draconids are likely to fly in the evening hours than in the morning hours after midnight. This shower is usually a sleeper, producing only a handful of languid meteors per hour in most years. But watch out if the Dragon awakes! In rare instances, fiery Draco has been known to spew forth many hundreds of meteors in a single hour.

October’s Draconid meteor shower is sometimes called the Giacobinids. This shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years. European observers saw over 600 meteors per hour in 2011.

The Draconid shower is active between October 6 and 10. As noted above, the best evening to watch in 2021 is likely October 8. Try the evenings of October 7 and 9 also. Be sure to watch in a dark sky.

Star chart of summer triangle with line pointing to dragon's eyes stars.
Those at southerly latitudes will have a tough time finding the Big Dipper at this time of you. Instead, star-hop from the Summer Triangle to locate Eltanin and Rastaban, near the Draconids’ radiant point. At nightfall in October, look overhead for the Summer Triangle. Draw an imaginary line from Altair through Vega in the Summer Triangle. That line will point to Eltanin and Rastaban.

Where is the radiant point of the Draconid shower?

The Draconid meteors, when traced backward, radiate from the head of Draco the Dragon, near the stars Eltanin and Rastaban. See the two charts above.

The Draconids are best in the evening, instead of before dawn, because the winged Dragon, the shower’s radiant point, flies highest in the October sky at nightfall. As night passes – no matter where you are on Earth – the radiant point sinks lower in your sky.

You don’t have to locate Draco the Dragon to watch the Draconids. These meteors fly every which way through the starry sky. But finding Draco is fun, and relatively easy. The two charts below show you two easy ways to find it. You can star-hop from the Big Dipper. Or you can star-hop from the Summer Triangle.

Thin horizontal white streak in star field with a large bright bluish star toward the center.
Draconid meteor seen from Italy in 2011, flying near the bright star Vega in the constellation Lyra. The stars Eltanin and Rastaban in Draco – near the radiant of the Draconid meteor shower – shine close to Vega. Image via Vittorio Poli.
Shooting stars above desert mountains with tall suguaro cactuses in the foreground.
Composite image of Draconid meteor shower seen near Tucson, Arizona, in 2013, by our friend Sean Parker Photography.

How many Draconids will you see?

In general, the Draconids aren’t a rich shower, unless their parent comet is nearby. They typically produce only about five meteors per hour.

This annual meteor shower happens when Earth in its orbit crosses the orbital path of Comet 21P/Giacobini-Zinner. Debris left behind by this comet collides with the Earth’s upper atmosphere to burn up as Draconid meteors. This comet has an orbital period of about 6.6 years. It’s about six times more distant at its farthest point from the sun than at its nearest point. At aphelion – its most distant point – it’s farther out than the planet Jupiter. At perihelion – its closest point to the sun – it’s about the Earth’s distance from the sun.

On rare occasions – when the peak of the shower coincides with the comet’s perihelion – this shower has been known to rain down hundreds or even thousands of meteors in an hour.

The last perihelion of the comet was September 10, 2018. On that same night, Comet 21P/Giacobini-Zinner came closer to Earth than it had in 72 years. Consequently, the Draconids had an outburst in 2018. We posted best pics of the comet as it swept safely past.

Because this comet has an orbital period of nearly seven years, the next perihelion won’t come until 2025. So we’re not expecting any outburst this year. But, then, no one really knows for sure.

For people who enjoy meteor showers, that’s part of the fun! As a wise person once said, meteor showers are like fishing. You go, and sometimes you catch something.

Star field with fuzzy green spot and small slightly oblong cluster of very many stars.
View larger. | Greg Hogan in Kathleen, Georgia, U.S., wrote on September 10, 2018: “I was able to grab a shot of Comet 21P/Giacobini-Zinner (top left), alongside Messier 37 (star cluster, bottom right). The comet looked like a little fuzzy spot through the ‘scope.” Thanks, Greg! See more photos of Comet 21P/Giacobini-Zinner in 2018.

The Draconids have a rich history.

Most meteors in annual showers are named for the constellation from which they appear to radiate, in this case Draco the Dragon.

Draco’s meteors, however, are sometimes called the Giacobinids. That name honors the role this comet played in the history of astronomers’ understanding of meteors.

Michel Giacobini discovered this comet on December 20, 1900. So the comet received his name. Another sighting in 1913 added Zinner to the comet’s name. Thus 21P/Giacobini-Zinner. Astronomers in the early 20th century speculated that meteors and comets were related. So of course they tried to link various comets to the spectacular showers of meteors that sometimes rain down in Earth’s sky.

Comet 21P/Giacobini-Zinner was a particularly tempting object about which to make predictions. Remember, it returns every 6.6 years, and its closest point to the sun is about the same as Earth’s distance.

What’s more, Comet Giacobini-Zinner didn’t disappoint the astronomers.

The Draconid meteor shower produced awesome meteor displays in 1933 and 1946. Observers saw thousands of meteors per hour in those years.

The relationship between 21P/Giacobini-Zinner and its meteors – so studied and discussed among professional astronomers in the early 20th century – probably explains why the Draconid meteor shower sometimes goes by the name Giacobinids.

For a taste of history related to this shower, go to the Astronomy Abstract Service from the Smithsonian and NASA. And find a 1934 article called The Meteors from Giacobini’s Comet by C.C. Wylie. It’s an account of the famed meteor storm of 1933.

Can you see the Draconids from the Southern Hemisphere?

It’s possible. But if you’re so far south that the radiant point in the constellation Draco doesn’t rise above your horizon, or rises only briefly, you won’t catch many.

As seen from the Southern Hemisphere, you would have to be rather close to the equator in order to see Draco’s stars. Suppose you live in northern Australia – say Darwin, Northern Territory, Australia – which is at 12 degrees south latitude. If so, you’d be able to see the stars Rastaban and Eltanin very close to your north-northwest horizon at nightfall in early October (given an unobstructed northern horizon). These stars would set at fairly early evening. And so you wouldn’t see the head of Draco again until nightfall the following evening.

Why early evening? It’s because, no matter where you live worldwide, the head of Draco reaches upper transit (highest point in your sky) at around 5 p.m. local time in early October.

Thus, from latitudes in the Southern Hemisphere – even those as far north as northern Australia – you’d have a very narrow window for seeing meteors. If you’re in the Southern Hemisphere, and you’re really wanting to see a Draconid, try looking as soon as it gets really dark on October 7 and 8. And don’t expect much.

Starry sky with faint Milky Way and short bright streaks.
Photo composite – 5 Draconid meteors in less than an hour – on October 7, 2017, from Stephanie Longo at Pike National Forest in Tarryall, Colorado.

Bottom line: In 2021, the Draconid meteor shower – also called the Giacobinids – will probably produce the most meteors on the evening of October 8.

EarthSky meteor shower guide for 2021

The post Draconid meteor shower 2021 will peak October 8 first appeared on EarthSky.



from EarthSky https://ift.tt/3mhrIsc
Star chart with set of radial arrows at one end of constellation Draco.
Watch for the short-lived Draconid meteor shower at nightfall and early evening on October 8, 2021. This chart faces northward at nightfall in October. The Big Dipper sits low in the northwest. From the southern U.S. and comparable latitudes, in October, obstructions on your northern horizon might hide the Big Dipper from view. From farther south — say, the Southern Hemisphere — you won’t see the Dipper at all in the evening at this time of year. However, if you can spot it low in the sky, use the Big Dipper to star-hop to the star Polaris. Polaris marks the end star in the handle of the Little Dipper. Got all these stars? Then you should also be able to spot Eltanin and Rastaban, the Draconids’ radiant point, high in the northwest sky at nightfall in early October. Draconid meteors radiate from near these stars, which are known as the Dragon’s Eyes.

Draconid meteor shower 2021

Unlike many meteor showers, the Draconids are short-lived. In 2021, watch these meteors at nightfall and early evening on October 8. You might catch some on the nights before and after, as well. Fortunately, the thin waxing crescent moon sets before nightfall and won’t hinder this year’s Draconid shower. The radiant point for the Draconid meteor shower almost coincides with the head of the constellation Draco the Dragon in the northern sky. That’s why the Draconids are best viewed from the Northern Hemisphere. The Draconid shower is a real oddity, in that the radiant point stands highest in the sky as darkness falls. That means that, unlike many meteor showers, more Draconids are likely to fly in the evening hours than in the morning hours after midnight. This shower is usually a sleeper, producing only a handful of languid meteors per hour in most years. But watch out if the Dragon awakes! In rare instances, fiery Draco has been known to spew forth many hundreds of meteors in a single hour.

October’s Draconid meteor shower is sometimes called the Giacobinids. This shower produced awesome meteor displays in 1933 and 1946, with thousands of meteors per hour seen in those years. European observers saw over 600 meteors per hour in 2011.

The Draconid shower is active between October 6 and 10. As noted above, the best evening to watch in 2021 is likely October 8. Try the evenings of October 7 and 9 also. Be sure to watch in a dark sky.

Star chart of summer triangle with line pointing to dragon's eyes stars.
Those at southerly latitudes will have a tough time finding the Big Dipper at this time of you. Instead, star-hop from the Summer Triangle to locate Eltanin and Rastaban, near the Draconids’ radiant point. At nightfall in October, look overhead for the Summer Triangle. Draw an imaginary line from Altair through Vega in the Summer Triangle. That line will point to Eltanin and Rastaban.

Where is the radiant point of the Draconid shower?

The Draconid meteors, when traced backward, radiate from the head of Draco the Dragon, near the stars Eltanin and Rastaban. See the two charts above.

The Draconids are best in the evening, instead of before dawn, because the winged Dragon, the shower’s radiant point, flies highest in the October sky at nightfall. As night passes – no matter where you are on Earth – the radiant point sinks lower in your sky.

You don’t have to locate Draco the Dragon to watch the Draconids. These meteors fly every which way through the starry sky. But finding Draco is fun, and relatively easy. The two charts below show you two easy ways to find it. You can star-hop from the Big Dipper. Or you can star-hop from the Summer Triangle.

Thin horizontal white streak in star field with a large bright bluish star toward the center.
Draconid meteor seen from Italy in 2011, flying near the bright star Vega in the constellation Lyra. The stars Eltanin and Rastaban in Draco – near the radiant of the Draconid meteor shower – shine close to Vega. Image via Vittorio Poli.
Shooting stars above desert mountains with tall suguaro cactuses in the foreground.
Composite image of Draconid meteor shower seen near Tucson, Arizona, in 2013, by our friend Sean Parker Photography.

How many Draconids will you see?

In general, the Draconids aren’t a rich shower, unless their parent comet is nearby. They typically produce only about five meteors per hour.

This annual meteor shower happens when Earth in its orbit crosses the orbital path of Comet 21P/Giacobini-Zinner. Debris left behind by this comet collides with the Earth’s upper atmosphere to burn up as Draconid meteors. This comet has an orbital period of about 6.6 years. It’s about six times more distant at its farthest point from the sun than at its nearest point. At aphelion – its most distant point – it’s farther out than the planet Jupiter. At perihelion – its closest point to the sun – it’s about the Earth’s distance from the sun.

On rare occasions – when the peak of the shower coincides with the comet’s perihelion – this shower has been known to rain down hundreds or even thousands of meteors in an hour.

The last perihelion of the comet was September 10, 2018. On that same night, Comet 21P/Giacobini-Zinner came closer to Earth than it had in 72 years. Consequently, the Draconids had an outburst in 2018. We posted best pics of the comet as it swept safely past.

Because this comet has an orbital period of nearly seven years, the next perihelion won’t come until 2025. So we’re not expecting any outburst this year. But, then, no one really knows for sure.

For people who enjoy meteor showers, that’s part of the fun! As a wise person once said, meteor showers are like fishing. You go, and sometimes you catch something.

Star field with fuzzy green spot and small slightly oblong cluster of very many stars.
View larger. | Greg Hogan in Kathleen, Georgia, U.S., wrote on September 10, 2018: “I was able to grab a shot of Comet 21P/Giacobini-Zinner (top left), alongside Messier 37 (star cluster, bottom right). The comet looked like a little fuzzy spot through the ‘scope.” Thanks, Greg! See more photos of Comet 21P/Giacobini-Zinner in 2018.

The Draconids have a rich history.

Most meteors in annual showers are named for the constellation from which they appear to radiate, in this case Draco the Dragon.

Draco’s meteors, however, are sometimes called the Giacobinids. That name honors the role this comet played in the history of astronomers’ understanding of meteors.

Michel Giacobini discovered this comet on December 20, 1900. So the comet received his name. Another sighting in 1913 added Zinner to the comet’s name. Thus 21P/Giacobini-Zinner. Astronomers in the early 20th century speculated that meteors and comets were related. So of course they tried to link various comets to the spectacular showers of meteors that sometimes rain down in Earth’s sky.

Comet 21P/Giacobini-Zinner was a particularly tempting object about which to make predictions. Remember, it returns every 6.6 years, and its closest point to the sun is about the same as Earth’s distance.

What’s more, Comet Giacobini-Zinner didn’t disappoint the astronomers.

The Draconid meteor shower produced awesome meteor displays in 1933 and 1946. Observers saw thousands of meteors per hour in those years.

The relationship between 21P/Giacobini-Zinner and its meteors – so studied and discussed among professional astronomers in the early 20th century – probably explains why the Draconid meteor shower sometimes goes by the name Giacobinids.

For a taste of history related to this shower, go to the Astronomy Abstract Service from the Smithsonian and NASA. And find a 1934 article called The Meteors from Giacobini’s Comet by C.C. Wylie. It’s an account of the famed meteor storm of 1933.

Can you see the Draconids from the Southern Hemisphere?

It’s possible. But if you’re so far south that the radiant point in the constellation Draco doesn’t rise above your horizon, or rises only briefly, you won’t catch many.

As seen from the Southern Hemisphere, you would have to be rather close to the equator in order to see Draco’s stars. Suppose you live in northern Australia – say Darwin, Northern Territory, Australia – which is at 12 degrees south latitude. If so, you’d be able to see the stars Rastaban and Eltanin very close to your north-northwest horizon at nightfall in early October (given an unobstructed northern horizon). These stars would set at fairly early evening. And so you wouldn’t see the head of Draco again until nightfall the following evening.

Why early evening? It’s because, no matter where you live worldwide, the head of Draco reaches upper transit (highest point in your sky) at around 5 p.m. local time in early October.

Thus, from latitudes in the Southern Hemisphere – even those as far north as northern Australia – you’d have a very narrow window for seeing meteors. If you’re in the Southern Hemisphere, and you’re really wanting to see a Draconid, try looking as soon as it gets really dark on October 7 and 8. And don’t expect much.

Starry sky with faint Milky Way and short bright streaks.
Photo composite – 5 Draconid meteors in less than an hour – on October 7, 2017, from Stephanie Longo at Pike National Forest in Tarryall, Colorado.

Bottom line: In 2021, the Draconid meteor shower – also called the Giacobinids – will probably produce the most meteors on the evening of October 8.

EarthSky meteor shower guide for 2021

The post Draconid meteor shower 2021 will peak October 8 first appeared on EarthSky.



from EarthSky https://ift.tt/3mhrIsc

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