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Forum » SpaceEngine » Science and Astronomy Discussions » Astrophotography (Post your astrophotos here)
Astrophotography
FastFourierTransformDate: Wednesday, 04.02.2015, 09:13 | Message # 436
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Quote HarbingerDawn ()
Green comets are not very rare. The relatively recent comet Lemmon was also green.


Yes surely. I have seen many green comets. But what I mean is about morphology. The coma and the tail of those comets looks totally different and that should be shown on SE.

For example, this is a comparison of Lovejoy and an Hale Bopp. You can see that they look like totally different objects. The tail of lovejoy is quite awesome by the way, it has structured clumps and is not like a tenous spray (like in hale bopp):





Lovejoy has a very narrow tail/tails - hale bopp has not
lovejoy has a green spherical coma differentciated form the rest of the body - hale bopp doesn't

Credit for the first image: Gerald Rhemann
Credit for the second image: E. Kolmhofer and H. Raab


Edited by FastFourierTransform - Saturday, 07.02.2015, 00:44
 
midtskogenDate: Thursday, 12.02.2015, 20:31 | Message # 437
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A nice fireball this evening.






NIL DIFFICILE VOLENTI
 
WatsisnameDate: Friday, 13.02.2015, 23:49 | Message # 438
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Quote FastFourierTransform ()

For example, this is a comparison of Lovejoy and an Hale Bopp. You can see that they look like totally different objects. The tail of lovejoy is quite awesome by the way, it has structured clumps and is not like a tenous spray (like in hale bopp):


The difference in morphology is simply the presence of a dust tail for Hale-Bopp.

Both comets have an ion tail, which is blue for Hale-Bopp but greenish for Lovejoy because of fluorescing C2. Ion tails are generally more structured than dust tails, and are always aimed more directly away from the sun (dust particles aren't accelerated by the solar wind as much and so they keep more to the orbital path.) That you don't see a spherical coma for Hale-Bopp is also because it is being swamped by the dust emission.





 
TemperateTerraIsBestDate: Saturday, 14.02.2015, 04:27 | Message # 439
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Weird.. the picture and color wont show. cry




Sample Text

Edited by TemperateTerraIsBest - Saturday, 14.02.2015, 04:28
 
WatsisnameDate: Monday, 16.02.2015, 06:24 | Message # 440
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Hooray for clear skies again. Here's an unedited shot I grabbed last night:






 
spacerDate: Tuesday, 17.02.2015, 16:51 | Message # 441
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This is how you see the sky in naked eye?!




"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer
 
DeathStarDate: Tuesday, 17.02.2015, 17:15 | Message # 442
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Quote spacer ()
This is how you see the sky in naked eye?!


Just because it is unedited does not mean that is how the human eye would see it.
 
WatsisnameDate: Wednesday, 18.02.2015, 01:12 | Message # 443
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Quote spacer ()
This is how you see the sky in naked eye?!


No, the camera picks up a lot more light than the eye can, especially with a long (this was 20s) exposure. The limiting visual magnitude here is about 6.0, whereas the faintest stars captured in the shot are about magnitude 9. You can also see comet Lovejoy and M33 (barely), which I've never been able to spot with my eyes.





 
midtskogenDate: Thursday, 19.02.2015, 20:08 | Message # 444
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Last night:


And the night before, another meteor and faint aurora:

Attachments: 9903725.jpg(155Kb)





NIL DIFFICILE VOLENTI


Edited by midtskogen - Thursday, 19.02.2015, 20:12
 
FireintheholeDate: Friday, 20.02.2015, 14:11 | Message # 445
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Beautiful shot, as always Watsisname! smile
Quote spacer ()
This is how you see the sky in naked eye?!

A dark sky looks far more impressive to the naked eye ;)
Quote Watsisname ()
No, the camera picks up a lot more light than the eye can, especially with a long (this was 20s) exposure. The limiting visual magnitude here is about 6.0, whereas the faintest stars captured in the shot are about magnitude 9. You can also see comet Lovejoy and M33 (barely), which I've never been able to spot with my eyes.

Hm, with a NELM of +6 you should be able to distinguish M33. I did it myself under such conditions, with M33 being about 45 degrees over the horizon. Though averted vision was required.





Love SpaceEngine!

Edited by Fireinthehole - Friday, 20.02.2015, 14:11
 
WatsisnameDate: Friday, 20.02.2015, 21:12 | Message # 446
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Quote Fireinthehole ()
A dark sky looks far more impressive to the naked eye ;)


Indeed it does. smile A truly dark sky even gives me an (obviously false) perception of depth to the sky, and I'm always amazed at how it can contain so many stars and yet still be so dark. Good old "Olber's paradox" mathematics for you.

Quote Fireinthehole ()
Hm, with a NELM of +6 you should be able to distinguish M33. I did it myself under such conditions, with M33 being about 45 degrees over the horizon. Though averted vision was required.


If you could spot it from a flat 6 then I'm impressed. smile At magnitude 5.7 the contrast between M33 and the background sky is very low (as evident by the long exposure), and so it is a considered a difficult averted vision target. I've never managed it, but I have a very hard time spotting diffuse objects with such low surface brightnesses in general. A half magnitude or more difference makes it a lot easier.





 
FireintheholeDate: Friday, 20.02.2015, 22:58 | Message # 447
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Quote Fireinthehole ()
Indeed it does. A truly dark sky even gives me an (obviously false) perception of depth to the sky, and I'm always amazed at how it can contain so many stars and yet still be so dark. Good old "Olber's paradox" mathematics for you.

I remember the first time I saw a truly dark sky. The first thing I thought, was that I could not blame those in the middle ages, who believed all the stars were located at the same distance, because that was my impression too! smile
Quote Watsisname ()
If you could spot it from a flat 6 then I'm impressed. At magnitude 5.7 the contrast between M33 and the background sky is very low (as evident by the long exposure), and so it is a considered a difficult averted vision target. I've never managed it, but I have a very hard time spotting diffuse objects with such low surface brightnesses in general. A half magnitude or more difference makes it a lot easier.

I saw a star that I know have an apparent magnitude of about +6.1, and I saw M33 with averted vision. Very hard to see though, I was out for about 20 minutes before my eyes had got used to the darkness.





Love SpaceEngine!

Edited by Fireinthehole - Saturday, 21.02.2015, 11:34
 
SolarLinerDate: Sunday, 22.02.2015, 12:29 | Message # 448
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First capture from a guy on reddit at /r/space, using his new solar telescope. (So not mine unfortunately)



That's hot in all different kinds of ways.





custom landing page to share: http://bit.ly/spaceengine
 
midtskogenDate: Sunday, 22.02.2015, 18:18 | Message # 449
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I noticed a red dot next to Venus tonight. It's Mars (had to look it up). That might create a good picture. Has anyone had a go?




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WatsisnameDate: Monday, 23.02.2015, 05:29 | Message # 450
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I got this one the other day when they formed a trio with the Moon. Had some clouds though.






 
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