Comet Catalina on December 7 by Geraint Smith in New Mexico.
UPDATE DECEMBER 26, 2015: Comet C/2013 US10 (Catalina) has not become the bright comet many hoped for. It still requires optical aid to be seen. But if you received a telescope or binoculars for Christmas, this comet would make a fantastic target. Using binoculars, the comet should appear as a small fuzzy patch of light in your predawn sky.
When and where should I begin to look?
What will Comet Catalina look like?
When is the next predicted comet visible to the eye alone?
View larger. | Comet Catalina caught on December 6, 2015 by Brian D. Ottum in Rancho Hidalgo, New Mexico.
When and where should I begin to look? The comet has been in our predawn sky throughout this past month. Its brightness has been pretty steady. As the New Year begins, it will gradually become a night sky object.
The comet was closest to the sun on November 15, so it is moving away from the sun now. But it’s still drawing closer to the Earth. On January 17, 2016, Comet Catalina will be at its closest point to Earth, about some 68 million miles (110 million km) away. That’s in contrast to the moon’s distance of about a quarter million miles … so you can see the comet is coming nowhere near us. Still, as it passes closest to Earth during mid-January, we might see the comet appearing a bit brighter than now.
By all reports, Comet Catalina has never risen above magnitude 6, the limit of visibility to the unaided eye. But it has hovered just below that limit. The moon was full on December 25, meaning its light is flooding the predawn sky now. But the moon will be waning, becoming smaller in our sky, in the weeks ahead. If you go to a location far from city lights – say, beginning around New Year’s, when the moon is waning in the predawn sky, you might be able to sweep with your binoculars and find the comet.
Remember … the comet is moving slowly across our sky’s dome. Below you’ll find some charts that should help you find it. Or check out this chart from skyandtelescope.com.
Comet Catalina images taken December 4, 2015 by Doug Durig. Here, you can see some detail in the comet’s tail …
What will Comet Catalina look like? The comet’s tail has been some 500,000 miles (800,000 km) long! And it has shown a double tail. Some photos have captured even more detail. With binoculars, though, you’re likely to spot the comet as a small, circular, hazy patch. You might see at most a short tail for this comet. It’s likely you won’t see any color at all.
Telescopes will provide a better view. Even while observing visually with a telescope, you will not see the green color of the comet, as shown some photos. That color is mainly seen in pictures of this comet, and many comets. Cameras are more sensitive than the human eye and after a few seconds or minutes of exposure, they provide very good views of the colors that exist in comets.
But visual observers using telescopes in December, 2015, might be able to glimpse a hint of Comet Catalina’s green coma or cometary atmosphere.
And, by the way, the green color we see in comets is from gases like diatomic carbon.
View larger. | Greg Hogan in Kathleen, Georgia caught this photo on December 7, 2015. He wrote: “So what are the odds? I was going through the images from Dec 7th and noticed that in one of the shots there was two meteors! One was the tail end of a bright one, and one is faint. I saw some large bright ones that morning but was not sure if they were in the frame. It seems part of one was.”
Here are some important dates.
October 31, 2013. The Catalina Sky Survey in Arizona discovered a comet, later called C/2013 US10 (Catalina). At first, astronomers thought it was a rocky or metallic asteroid, but further observations confirmed it as an icy comet.
November 15, 2015. Comet Catalina was at perihelion or closest to the sun. It did not come as close to the sun as some comets do. At closest approach to our star, the comet was moving between the orbits of planets Earth and Venus. Its perihelion distance was 0.82 AU from the sun (1 AU = 1 Earth-sun distance). Comet Catalina was traveling at a speed of 103,000 miles per hour (166,000 km/h) relative to the sun at perihelion.
November 23 to 30,2015. Comet Catalina became visible for Northern Hemisphere observers.
December 7,2015. Sky show! Comet Catalina was visible close to Venus and the waning moon.
December 31,2015. Comet will be approaching the apparent position of the star Arcturus on our sky’s dome. Another good photo opportunity.
January 1,2016. Comet Catalina will be passing very close to star Arcturus. An excellent reference to finding the comet in the sky!
January 17,2016. Comet Catalina will pass some 68 million miles (110 million km) from Earth. That’s very, very far from Earth – hundreds of times farther than the moon’s distance. So there is no danger of a collision. That said, let’s talk about the size of the comet’s nucleus or core. Some estimates indicate the nucleus of Comet Catalina ranges between 4 and 20 kilometers in diameter.
January 1, 2016, from 2 a.m. to sunrise, local time. The comet will be very near the bright star Arcturus in the constellation Bootes. Photo opportunity!
When is the next predicted comet visible to the eye alone? The next predicted comet that may be reach visibility to the unaided eye – and be really easy to spot – is Comet 46P/Wirtanen. It will appear as a sky gift for Christmas of 2018.
Although Comet 46P may show a magnitude of 3 or 4, there is always the possibility that a newly found comet will provide a good celestial show prior to that time.
Bottom line: Comet C/2013 US10 (Catalina) is now visible in binoculars, in December, 2015. When and where to look, what to expect, some important dates to remember.
Look here for a chart from skyandtelescope.com showing the comet on various dates
from EarthSky http://ift.tt/1NmOSCR
Comet Catalina on December 7 by Geraint Smith in New Mexico.
UPDATE DECEMBER 26, 2015: Comet C/2013 US10 (Catalina) has not become the bright comet many hoped for. It still requires optical aid to be seen. But if you received a telescope or binoculars for Christmas, this comet would make a fantastic target. Using binoculars, the comet should appear as a small fuzzy patch of light in your predawn sky.
When and where should I begin to look?
What will Comet Catalina look like?
When is the next predicted comet visible to the eye alone?
View larger. | Comet Catalina caught on December 6, 2015 by Brian D. Ottum in Rancho Hidalgo, New Mexico.
When and where should I begin to look? The comet has been in our predawn sky throughout this past month. Its brightness has been pretty steady. As the New Year begins, it will gradually become a night sky object.
The comet was closest to the sun on November 15, so it is moving away from the sun now. But it’s still drawing closer to the Earth. On January 17, 2016, Comet Catalina will be at its closest point to Earth, about some 68 million miles (110 million km) away. That’s in contrast to the moon’s distance of about a quarter million miles … so you can see the comet is coming nowhere near us. Still, as it passes closest to Earth during mid-January, we might see the comet appearing a bit brighter than now.
By all reports, Comet Catalina has never risen above magnitude 6, the limit of visibility to the unaided eye. But it has hovered just below that limit. The moon was full on December 25, meaning its light is flooding the predawn sky now. But the moon will be waning, becoming smaller in our sky, in the weeks ahead. If you go to a location far from city lights – say, beginning around New Year’s, when the moon is waning in the predawn sky, you might be able to sweep with your binoculars and find the comet.
Remember … the comet is moving slowly across our sky’s dome. Below you’ll find some charts that should help you find it. Or check out this chart from skyandtelescope.com.
Comet Catalina images taken December 4, 2015 by Doug Durig. Here, you can see some detail in the comet’s tail …
What will Comet Catalina look like? The comet’s tail has been some 500,000 miles (800,000 km) long! And it has shown a double tail. Some photos have captured even more detail. With binoculars, though, you’re likely to spot the comet as a small, circular, hazy patch. You might see at most a short tail for this comet. It’s likely you won’t see any color at all.
Telescopes will provide a better view. Even while observing visually with a telescope, you will not see the green color of the comet, as shown some photos. That color is mainly seen in pictures of this comet, and many comets. Cameras are more sensitive than the human eye and after a few seconds or minutes of exposure, they provide very good views of the colors that exist in comets.
But visual observers using telescopes in December, 2015, might be able to glimpse a hint of Comet Catalina’s green coma or cometary atmosphere.
And, by the way, the green color we see in comets is from gases like diatomic carbon.
View larger. | Greg Hogan in Kathleen, Georgia caught this photo on December 7, 2015. He wrote: “So what are the odds? I was going through the images from Dec 7th and noticed that in one of the shots there was two meteors! One was the tail end of a bright one, and one is faint. I saw some large bright ones that morning but was not sure if they were in the frame. It seems part of one was.”
Here are some important dates.
October 31, 2013. The Catalina Sky Survey in Arizona discovered a comet, later called C/2013 US10 (Catalina). At first, astronomers thought it was a rocky or metallic asteroid, but further observations confirmed it as an icy comet.
November 15, 2015. Comet Catalina was at perihelion or closest to the sun. It did not come as close to the sun as some comets do. At closest approach to our star, the comet was moving between the orbits of planets Earth and Venus. Its perihelion distance was 0.82 AU from the sun (1 AU = 1 Earth-sun distance). Comet Catalina was traveling at a speed of 103,000 miles per hour (166,000 km/h) relative to the sun at perihelion.
November 23 to 30,2015. Comet Catalina became visible for Northern Hemisphere observers.
December 7,2015. Sky show! Comet Catalina was visible close to Venus and the waning moon.
December 31,2015. Comet will be approaching the apparent position of the star Arcturus on our sky’s dome. Another good photo opportunity.
January 1,2016. Comet Catalina will be passing very close to star Arcturus. An excellent reference to finding the comet in the sky!
January 17,2016. Comet Catalina will pass some 68 million miles (110 million km) from Earth. That’s very, very far from Earth – hundreds of times farther than the moon’s distance. So there is no danger of a collision. That said, let’s talk about the size of the comet’s nucleus or core. Some estimates indicate the nucleus of Comet Catalina ranges between 4 and 20 kilometers in diameter.
January 1, 2016, from 2 a.m. to sunrise, local time. The comet will be very near the bright star Arcturus in the constellation Bootes. Photo opportunity!
When is the next predicted comet visible to the eye alone? The next predicted comet that may be reach visibility to the unaided eye – and be really easy to spot – is Comet 46P/Wirtanen. It will appear as a sky gift for Christmas of 2018.
Although Comet 46P may show a magnitude of 3 or 4, there is always the possibility that a newly found comet will provide a good celestial show prior to that time.
Bottom line: Comet C/2013 US10 (Catalina) is now visible in binoculars, in December, 2015. When and where to look, what to expect, some important dates to remember.
Look here for a chart from skyandtelescope.com showing the comet on various dates
from EarthSky http://ift.tt/1NmOSCR
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