View larger. | November 15, 2015 capture of Comet C/2013 US10 (Catalina) by Ajay Talwar in India. Visit Ajay’s astrophotography pages at ajaytalwar.com and aperturetelescopes.com.
UPDATE NOVEMBER 21, 2015. Comet Catalina was spotted on November 19 from the Indian Himalayas by astrophotographer Ajay Talwar. The comet was closest to the sun on November 15, 2015, so this might be one of the first observations of the celestial visitor after perihelion. Although Comet C/2013 US10 (Catalina) is still difficult to observe because of its closeness to the horizon just before sunrise, observations of the comet may improve in just a few days as it moves higher. A higher position in the sky will provide a better contrast and the next observations may provide a good idea of its brightenss, to see if it’s improving or not. By the end of this month, Comet Catalina might be visible to the eye at a visual magnitude of 5 or 6, which means it would be within the limit for viewing with the unaided eye from dark sky sites. It’ll be in the predawn sky, near the planets and moon in early December. Comets have been shown to be unpredictable, so it may become brighter or fainter. Sometimes comets even disintegrate. But this comet is well worth following! Follow the links below to learn more – and check back to this post periodically. We’ll provide updates.
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. | November 15, 2015 capture of Comet C/2013 US10 (Catalina) by Ajay Talwar in India. Visit Ajay’s astrophotography pages at ajaytalwar.com and aperturetelescopes.com.
View larger. | Comet C/2013 US10 (Catalina) on October 1, 2015 by José J. Chambó (cometografia.es).
View larger. | Photo of Comet C/2013 US10 (Catalina) by Efraín Morales of the Astronomical Society of the Caribbean.
When and where should I begin to look? Between mid-November and the end of the month, Comet Catalina will be located in the direction east – the direction of sunup – before the sun rises.
However, its proximity to the horizon means that the comet is difficult to see at this writing (November 9, 2015). We should have a better view of the comet beginning around the last week of November, and during all December.
When the new year begins, the comet will remain in our skies. Although it’ll be visible in the predawn skies by January 2016, the celestial visitor will gradually become a night sky object.
Remember … the comet is moving slowly across our sky’s dome. Below you’ll find some charts that should help you find it, when it comes into view.
Be sure to go to a dark site, away from city lights. At first, try using binoculars … then remove the binoculars, and try to see the comet with your eye alone.
November 23, 2015, 30 to 45 minutes before sunrise, local time. ‘Local time’ means the time on your clock, in all timezones. Illustration: Eddie Irizarry using Stellarium
November 30, 2015, 30 to 45 minutes before sunrise, local time. Illustration: Eddie Irizarry using Stellarium
What will Comet Catalina look like? Recent observations show the comet has developed a tail some 500,000 miles (800,000 km) long! Thus – in November, 2015 – binoculars are likely to show a short tail of this comet, while small telescopes will provide a nice view.
While observing visually with a telescope, you will not see the green color of the comet, as shown in the photo at the top of this post. 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 November, 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.
December 7, 2015, 30 to 45 minutes before sunrise. Comet Catalina will be close to Venus and the waning moon on this date. Illustration: Eddie Irizarry using Stellarium
December 8, 2015, 30 to 45 minutes before sunrise. Another opportunity to glimpse the comet near the waning moon. No one knows if the comet will be visible to the eye by this date, so binoculars should come in handy. Illustration: Eddie Irizarry using Stellarium
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 is at perihelion or closest to the sun. It will not become as close to the sun as some comets do. At closest approach to our star, the comet will be moving between the orbits of planets Earth and Venus. Its perihelion distance is 0.82 AU from the sun (1 AU = 1 Earth-sun distance). Comet Catalina is 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 starts to become visible for Northern Hemisphere observers.
December 7,2015. Sky show! Comet visible close to Venus and the waning moon. Hopefully, the comet will be visible to the eye by this time, but you never know. Either way … think photo opportunity.
December 31,2015. Comet 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 110 million kilometers (68 million miles) 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.
Meanwhile, C/2013 US10 (Catalina) is our Christmas celestial present for 2015.
The trajectory of this visitor from the Oort cloud suggests that after closest approach to the inner solar system, comet Catalina will be ejected and we will never see this comet again.
Bottom line: Comet C/2013 US10 (Catalina) will be visible in binoculars, and may become visible to the unaided eye in November, 2015. When and where to look, what to expect, some important dates to remember.
from EarthSky http://ift.tt/1NmOSCR
View larger. | November 15, 2015 capture of Comet C/2013 US10 (Catalina) by Ajay Talwar in India. Visit Ajay’s astrophotography pages at ajaytalwar.com and aperturetelescopes.com.
UPDATE NOVEMBER 21, 2015. Comet Catalina was spotted on November 19 from the Indian Himalayas by astrophotographer Ajay Talwar. The comet was closest to the sun on November 15, 2015, so this might be one of the first observations of the celestial visitor after perihelion. Although Comet C/2013 US10 (Catalina) is still difficult to observe because of its closeness to the horizon just before sunrise, observations of the comet may improve in just a few days as it moves higher. A higher position in the sky will provide a better contrast and the next observations may provide a good idea of its brightenss, to see if it’s improving or not. By the end of this month, Comet Catalina might be visible to the eye at a visual magnitude of 5 or 6, which means it would be within the limit for viewing with the unaided eye from dark sky sites. It’ll be in the predawn sky, near the planets and moon in early December. Comets have been shown to be unpredictable, so it may become brighter or fainter. Sometimes comets even disintegrate. But this comet is well worth following! Follow the links below to learn more – and check back to this post periodically. We’ll provide updates.
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. | November 15, 2015 capture of Comet C/2013 US10 (Catalina) by Ajay Talwar in India. Visit Ajay’s astrophotography pages at ajaytalwar.com and aperturetelescopes.com.
View larger. | Comet C/2013 US10 (Catalina) on October 1, 2015 by José J. Chambó (cometografia.es).
View larger. | Photo of Comet C/2013 US10 (Catalina) by Efraín Morales of the Astronomical Society of the Caribbean.
When and where should I begin to look? Between mid-November and the end of the month, Comet Catalina will be located in the direction east – the direction of sunup – before the sun rises.
However, its proximity to the horizon means that the comet is difficult to see at this writing (November 9, 2015). We should have a better view of the comet beginning around the last week of November, and during all December.
When the new year begins, the comet will remain in our skies. Although it’ll be visible in the predawn skies by January 2016, the celestial visitor will gradually become a night sky object.
Remember … the comet is moving slowly across our sky’s dome. Below you’ll find some charts that should help you find it, when it comes into view.
Be sure to go to a dark site, away from city lights. At first, try using binoculars … then remove the binoculars, and try to see the comet with your eye alone.
November 23, 2015, 30 to 45 minutes before sunrise, local time. ‘Local time’ means the time on your clock, in all timezones. Illustration: Eddie Irizarry using Stellarium
November 30, 2015, 30 to 45 minutes before sunrise, local time. Illustration: Eddie Irizarry using Stellarium
What will Comet Catalina look like? Recent observations show the comet has developed a tail some 500,000 miles (800,000 km) long! Thus – in November, 2015 – binoculars are likely to show a short tail of this comet, while small telescopes will provide a nice view.
While observing visually with a telescope, you will not see the green color of the comet, as shown in the photo at the top of this post. 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 November, 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.
December 7, 2015, 30 to 45 minutes before sunrise. Comet Catalina will be close to Venus and the waning moon on this date. Illustration: Eddie Irizarry using Stellarium
December 8, 2015, 30 to 45 minutes before sunrise. Another opportunity to glimpse the comet near the waning moon. No one knows if the comet will be visible to the eye by this date, so binoculars should come in handy. Illustration: Eddie Irizarry using Stellarium
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 is at perihelion or closest to the sun. It will not become as close to the sun as some comets do. At closest approach to our star, the comet will be moving between the orbits of planets Earth and Venus. Its perihelion distance is 0.82 AU from the sun (1 AU = 1 Earth-sun distance). Comet Catalina is 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 starts to become visible for Northern Hemisphere observers.
December 7,2015. Sky show! Comet visible close to Venus and the waning moon. Hopefully, the comet will be visible to the eye by this time, but you never know. Either way … think photo opportunity.
December 31,2015. Comet 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 110 million kilometers (68 million miles) 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.
Meanwhile, C/2013 US10 (Catalina) is our Christmas celestial present for 2015.
The trajectory of this visitor from the Oort cloud suggests that after closest approach to the inner solar system, comet Catalina will be ejected and we will never see this comet again.
Bottom line: Comet C/2013 US10 (Catalina) will be visible in binoculars, and may become visible to the unaided eye in November, 2015. When and where to look, what to expect, some important dates to remember.
from EarthSky http://ift.tt/1NmOSCR
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