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A Star of Space and Film
Rollie Hawk writes "Three years ago, light from V838 Monocerotis (a star about 20,000 light years from us) reached the Earth that showed the star exploding. The more politically correct term for what happened is "stellar outburst." In the time since, images from a pulse of light released during the outburst have been arriving here on Earth. In October of 2004, Hubble captured a beautiful image of the scene with the pulse lighting up interstellar gasses that encapsulated the area around this red giant (a star 600,000 times brighter than our Sun). The release of this photo just days ago seems rather timely, as it appears that some of Hubble's funding may be cut in the near future. There is also talk of eliminating the program entirely."
Superman escaping from the planet?
Here is NASA's Astronomy picture of the day site Astronomy picture of the day with the same picture and a brief explanation (with hyperlinks).
Enjoy
As I was reading the articles (Hey!, I'm new to Slashdot!!) it occured to me. We always say that the sun will end in billions of years, probably much more years that the human race will be able to exist. But the question I asked myself is, what would be the consequences of the outburst of a "nearby" star. I mean, would the shockwave be big enough to reach earth? Will the gases and radiations be able to reach earth??
If you go to the HST web site, you can see an entire series of images of V838 Mon over the past three years.
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y /i mg_display.php?pic=light_echo_graphic_030326_02,0. jpg
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http://hubblesite.org/newscenter/newsdesk/archi
Although the series _appears_ to show a shell of gas expanding outwards from the star, it does not. Instead, what we see is the expanding echo of light reflecting off gas and dust in the interstellar medium, between V838 Mon and the Earth. It might help to look at a nice diagram of the "light echo" effect provided by space.com:
http://www.space.com/php/multimedia/imagedispla
The European Space Agency also has a good description of the event:
http://www.space.com/scienceastronomy/light_ech
The fact that no material is actually shooting outwards into space as fast as the pictures appear to indicate -- that we are simply seeing a reflection of light as it moves through the gas cloud, like the beam of a flashlight swept through the air in a dusty room -- explains how the shell can _appear_ to expand outwards faster than light.
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Hubble has done exceptionally well. But it is an old horse, and instead of an expensive manned mission to fix it and keep it going for a few more years, I'd rather see the money put into a new telescope that incorporates all the lessons learned from Hubble. Namely, modules that can be replaced without a manned mission. I think we'd get a better value if we did something like that.
Remember, You are unique...just like everyone else.
Is there some ethnic minority exploding stars that will be offended??
A very interesting thing about this stellar outburst is the possibility to get a 3D image of the cloud surrounding the star. Images of this event taken months apart (like this sequence) show the flash of light as it expands, illuminating regions of space that form spherical shells around the star. This gives a unique insight into the actual threedimensional structure of the cloud, a bit like a CAT scan builds a 3D view from a sequence of planar 2D images. Pity we don't have (for all I know) one picture per day: it would have made a stunning movie! No to mention the scientific value...
Nuffsaid
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Don't know about his cat, but Schroedinger is definitely dead.
These images are made from spectral data not visible light(other than the fact the spectral data for the exposure MAY lie in the visible spectrum). The hubble is a digital camera but not like the type you have at home. The WFC3 (wide field planetary camera version 3) or the COS (Cosmic Origins Spectrograph) take the images. Exposure times can be many minutes,and the instruments are very sensitive and highly calibrated. In fact they are calibrated to a known light source and a known dark source before each exposure. There are also filters that can be applied before the light reaches the camera so that only wavelengths in a given spectral range hit the detectors. Then the images are sent to the ground as binary data as groups of spectral frequency bins which are then post-processed (a the Space Science Institute) to give the (false) color images. The colors are pretty close to correct but are not perfect. So, yea they ARE manufactured in some sense by the Gov't ;)
Hubble is nowhere near state of the art (some software in it is 25-30 yrs old) but it works and has exceeded the wildest expectations of it's builders. Kind of a Brooklyn Bridge in space, the first one built but still works great and setting a high standard.