APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21)

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APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21)

Post by APOD Robot » Wed Jan 21, 2015 5:05 am

Image The Complex Ion Tail of Comet Lovejoy

Explanation: What causes the structure in Comet Lovejoy's tail? Comet C/2014 Q2 (Lovejoy), which is currently at naked-eye brightness and near its brightest, has been showing an exquisitely detailed ion tail. As the name implies, the ion tail is made of ionized gas -- gas energized by ultraviolet light from the Sun and pushed outward by the solar wind. The solar wind is quite structured and sculpted by the Sun's complex and ever changing magnetic field. The effect of the variable solar wind combined with different gas jets venting from the comet's nucleus accounts for the tail's complex structure. Following the wind, structure in Comet Lovejoy's tail can be seen to move outward from the Sun even alter its wavy appearance over time. The blue color of the ion tail is dominated by recombining carbon monoxide molecules, while the green color of the coma surrounding the head of the comet is created mostly by a slight amount of recombining diatomic carbon molecules. The featured three-panel mosaic image was taken nine days ago from the IRIDA Observatory in Bulgaria. Comet Lovejoy made its closest pass to the Earth two weeks ago and will be at its closest to the Sun in about ten days. After that, the comet will fade as it heads back into the outer Solar System, to return only in about 8,000 years.

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by HellCat » Wed Jan 21, 2015 8:43 am

... made "its" closest pass ...

Towards the end of the paragraph.

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by starsurfer » Wed Jan 21, 2015 10:23 am

Would the structure of the tail be different is the Sun was going through a solar minimum?

hoohaw

Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by hoohaw » Wed Jan 21, 2015 10:46 am

starsurfer wrote:Would the structure of the tail be different is the Sun was going through a solar minimum?
...if...

yes

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by Boomer12k » Wed Jan 21, 2015 7:30 pm

Carbon monoxide....I guess the EPA will have to ban Comets in the future...

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same old idiot

Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by same old idiot » Wed Jan 21, 2015 7:34 pm

Screw this comet. I have been out in the middle of the desert and cannot see ANYTHING at all that looks like this.
No city lights to effect viewing, and I see nothing that looks like this.

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by Chris Peterson » Wed Jan 21, 2015 7:39 pm

same old idiot wrote:Screw this comet. I have been out in the middle of the desert and cannot see ANYTHING at all that looks like this.
No city lights to effect viewing, and I see nothing that looks like this.
The tail is too dim to see with the naked eye (a very experienced observer might make out some slight distortion of the coma, that's about it). From a dark site, the comet is easily seen with the naked eye. Even from areas with a fair degree of light pollution, it is easy and obvious in binoculars as a big fuzzy blob. Just the coma, though, no tail. And that's the best we're going to get visually, which demonstrates the value of imaging.
Chris

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by ta152h0 » Wed Jan 21, 2015 7:51 pm

" outer solar system " How far is that ?
Wolf Kotenberg

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by BMAONE23 » Wed Jan 21, 2015 8:16 pm

ta152h0 wrote:" outer solar system " How far is that ?
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=c ... ;cad=0#orb

Looks like the Aphelion distance is 1155.7175 AU

Visual_Astronomer

Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by Visual_Astronomer » Wed Jan 21, 2015 11:26 pm

Chris Peterson wrote:
same old idiot wrote:Screw this comet. I have been out in the middle of the desert and cannot see ANYTHING at all that looks like this.
No city lights to effect viewing, and I see nothing that looks like this.
The tail is too dim to see with the naked eye (a very experienced observer might make out some slight distortion of the coma, that's about it). From a dark site, the comet is easily seen with the naked eye. Even from areas with a fair degree of light pollution, it is easy and obvious in binoculars as a big fuzzy blob. Just the coma, though, no tail. And that's the best we're going to get visually, which demonstrates the value of imaging.
I was out at my dark site on Monday night and was able to see it with the naked eye - very faint, but I spotted it with no finder chart and only a vague idea of its location. The tail was easily visible with 11x70 binoculars. In the 20" it had a beautiful green/blue color similar to the APOD picture, and over two degrees of tail. It was quite a sight.

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by geckzilla » Wed Jan 21, 2015 11:28 pm

One dark site the comet is easily visible from is the ISS. https://www.flickr.com/photos/astrosama ... 145421888/
Just call me "geck" because "zilla" is like a last name.

firstmagnitude

Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by firstmagnitude » Thu Jan 22, 2015 1:00 am

Beautiful!

DavidGovett

Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by DavidGovett » Thu Jan 22, 2015 1:27 am

Shouldn't the comet have two tails, one in the diction of travel, the other ionized particles caused by the sun?

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by Chris Peterson » Thu Jan 22, 2015 3:16 am

dmiladinovich wrote:Why does the comet seem to have one larger central blue tail with red streams mixing with it? What is the red or brown gas? It was not mentioned in the description.
I don't see that. I see a very unsaturated blue complex of ion trails, with parts showing a little more blue and most close to gray. No intense colors in the tail at all.
Chris

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by Chris Peterson » Thu Jan 22, 2015 3:18 am

DavidGovett wrote:Shouldn't the comet have two tails, one in the diction of travel, the other ionized particles caused by the sun?
A comet can have two tails, one consisting of ionized atoms and the other of dust. Or it may have just one of these. This comet isn't very active, so it isn't producing a significant amount of dust. Just a weak ion tail.
Chris

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Re: APOD: The Complex Ion Tail of Comet Lovejoy (2015 Jan 21

Post by ta152h0 » Sat Jan 24, 2015 3:17 am

you never know what is in that box of chocolates
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