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New Supernova

In the video, he shows some pictures of stars in the area. Some of the dots were green. Are these chlorophyll stars? I didn't know there were green -- and Kelly green to boot -- stars.
 
11? Blurgh. There's so much light pollution where I am (it's even worse since the new highway and some exchanges were completed) that I can't even see 2.5-3.0 satellites like I used to. It would be so cool to watch an SN slowly brighten over time.

Oh well, maybe we'll have another SN 1006 some time.
http://en.wikipedia.org/wiki/SN_1006
 
marplots said:
In the video, he shows some pictures of stars in the area. Some of the dots were green. Are these chlorophyll stars? I didn't know there were green -- and Kelly green to boot -- stars.
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They may (I'd say very likely are) false colors photos. A green star is hard to imagine given the way black body radiation works. As a black body gets hotter, the peak of the radiation rises from the infrared into the red, then through the colors until it moves into the UV. The visible color that we see isn't the peak color, though, it is the sum of colors that are combined under the radiation curve. Red, orange, and yellow are pretty straight forward, because the brighter can override the dimmer; as the peak moves into green, though, there's both green and red combined mixed with it, even a little blue, and the result is "soft" white. As the peak moves into blue, the color becomes cold, or blue, white, and that's the way it appears as the peak progresses into the UV band (in fact, even getting a little colder, more bluish, but still white). That's why one sees red-hot iron, yellow-hot, then white-hot, and never anything in a pure green or blue color.

The green coloration might indicate some IR or UV band we cannot see directly ourselves, or it might be a temperature encoding.
 
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I just got in from observing it tonight - took three tries over a four hour period, but finally got it and the attendant galaxy
 
UnrepentantSinner said:
11? Blurgh. There's so much light pollution where I am (it's even worse since the new highway and some exchanges were completed) that I can't even see 2.5-3.0 satellites like I used to. It would be so cool to watch an SN slowly brighten over time.
Click to expand...

Just want to add that while I don't have a decent (or one at all for that matter) telescope and love all aspects of astronomy, I'm partial to naked eye and would love to be able to take friends, neighbors and coworkers outside at a particular time and say "look up".
 
shadron said:
They may (I'd say very likely are) false colors photos. A green star is hard to imagine given the way black body radiation works. As a black body gets hotter, the peak of the radiation rises from the infrared into the red, then through the colors until it moves into the UV. The visible color that we see isn't the peak color, though, it is the sum of colors that are combined under the radiation curve. Red, orange, and yellow are pretty straight forward, because the brighter can override the dimmer; as the peak moves into green, though, there's both green and red combined mixed with it, even a little blue, and the result is "soft" white. As the peak moves into blue, the color becomes cold, or blue, white, and that's the way it appears as the peak progresses into the UV band (in fact, even getting a little colder, more bluish, but still white). That's why one sees red-hot iron, yellow-hot, then white-hot, and never anything in a pure green or blue color.

The green coloration might indicate some IR or UV band we cannot see directly ourselves, or it might be a temperature encoding.
Click to expand...
No, man--It's cot a copper plating instead of iron!
 
shadron: The video is labelled with the instruments and filters - it's Hubble's WFPC2, filters F439W, F555W and F814W. Each number is broadly the wavelength in nm of the filter - it's basically a blue filter, one roughly equivalent to green, but the red is into the near IR rather than visual.
 
MG1962 said:
A nice new supernova is brightening in the galaxy M95. The current magnitude is about 13.2 and the star should get into the high 11s. M95 is very easy to find in the night sky at the moment due to its proximity to Mars - The downside is the galaxy's light is getting a little done over by the glare from Mars
http://blogs.discovermagazine.com/badastronomy/2012/03/23/more-m95-supernova-news-progenitor-found/
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Hilite by Daylightstar
M95 is nearly 10th magnitude, so no naked eye object. The SN even less so at 13th magnitude.
Both require a telescope to see and as such the glare of Mars at about three degrees of arc away plays no role. :)
 
UnrepentantSinner said:
Just want to add that while I don't have a decent (or one at all for that matter) telescope and love all aspects of astronomy, I'm partial to naked eye and would love to be able to take friends, neighbors and coworkers outside at a particular time and say "look up".
Click to expand...

Iridium flares.
I like to amuse my children by pointing to a certain position in the sky, and count down to the event (having an accurate time reference is important) and sure enough, there is a bright flash. It only lasts a few seconds, but gets a good 'Wow' response.
Pass predictions available here; among other places: http://www.heavens-above.com/

V.
 
Verde said:
Iridium flares.
I like to amuse my children by pointing to a certain position in the sky, and count down to the event (having an accurate time reference is important) and sure enough, there is a bright flash. It only lasts a few seconds, but gets a good 'Wow' response.
Pass predictions available here; among other places: http://www.heavens-above.com/

V.
Click to expand...

After I spotted an amazing Iridium flare in 2008 and couldn't identify it, I learned of that site and have done just as I/you have described with co-workers. Even had a ISS overpass at shift change and there was 5 of us standing around outside watching it.

:thumbsup:
 
edd said:
shadron: The video is labelled with the instruments and filters - it's Hubble's WFPC2, filters F439W, F555W and F814W. Each number is broadly the wavelength in nm of the filter - it's basically a blue filter, one roughly equivalent to green, but the red is into the near IR rather than visual.
Click to expand...

I would presume than that the green star is really a green or near green star (surface temp around 4500 degrees C). The red filter is keeping a large amount of the complimentary light from being visible, since it tends toward the infrared, so green is showing up.

Thanks for the info, edd.
 
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