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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."
I find it sad that while allocating over $100 billion on war, Bush denies $1 billion for hubble.
Images like this are a lot more beautiful than the carnage of another car bomb.
Anyways, before our Sun could go supernova, it would have to swell to red giant so large that it would engulf the Earth, so it's a moot point.
In that regard though, the explosion would be more than enough to destroy Pluto without slowing down. The Sun makes up 99.9% of the mass in our solar system, and so the planets wouldn't really have much of a defense.
Fnord.
In all of the discussions over the cost of a manned vs. robotic mission to upgrade Hubble, one question I haven't heard anyone ask is what would it cost to replace it with a new telescope?
I've seen articles with cost estimates ranging from $1 - $2 Billion for a service mission. Given what we've learned with Hubble about the true costs of operating a space based telescope, couldn't we build a new telescope for relatively less than we originally spent on Hubble?
Given the choice of fixing Hubble for say $1-$2 Billion, or replacing it with a telescope with more capability and servicability for say $2-$3 Billion, I'd go for the replacement.
Todd
For instance our Sun outputs 3.8e26 watts per second. This object is much more luminous. In space, there is no atmosphere. However, there is dust, but it tends to stick together in clouds, and not scatter itself all around. In fact, the picture you're looking at is a great part dust (see all the dark marbling?) What media there is between stars is not very dense (on the order of one atom per cm^3!) and does not cause a lot of interference. As far as gravitational lensing, that is only a factor when there is a large object between the source and the destination, and this is a pretty straight shot.
The image does degrade by a factor of 1/r^2, however this can be accounted for by using a very long exposure time (weeks if necessary) that is why the other stars look so bright.
HTH
Fnord.
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.