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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
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.
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??
I think it's most impressive when seen in a time-lapse. Not sure if there's any site that has all the images or a month-by-month or something, but I had this image :2 003/20030326-HST-Light-echo-from-star-V838-Mon.jpg
http://www.gothard.hu/astronomy/astronews/images/
: bookmarked for a long time now - just killed it this morning(!)
You have to see it to really appreciate both the beauty and the sheer vastness and speed.
If anybody has better images, or more images of different points in time, please do reply!
If you go to the HST web site, you can see an entire series of images of V838 Mon over the past three years.
v e/ releases/2005/02/image/a
y /i mg_display.php?pic=light_echo_graphic_030326_02,0. jpg
o _0 30326.html
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
Is there some ethnic minority exploding stars that will be offended??
What's interesting, at least when you first think about it, is how the sphere of influence spans 14 light-years less than 3 years after we detected its "flash".
Of course, it's not really going faster-than-light, it's just a matter of perespective. The event happened 20,000 years ago, and the portion of the 14 ly radius sphere that's approximately 11 ly closer to us than the star should now be visible. That is, it took ~20,000 years for the flash to reach us, and ~(20,000+14-11) = ~(20,000+3) years for that portion of the echo to reach us.
Ben Hocking
Need a professional organizer?
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
________
Don't know about his cat, but Schroedinger is definitely dead.
It's not really *that* detailed- each pixel is at the very least a few hundred thousand kilometers across. And it's so sharp because the light is traveling through space, so there's nothing to blur the image or attenuate its intensity (besides the inverse-square law).
As a very *amateur* backyard astronomer,
I think there is nothing wrong with the question. You actually get this kind of reaction almost all the time when people peer through a telescope for the first time expecting to see the types of images that appear on telescope boxes, in books, and in the media. Fabulous images of space that look nothing like that to the naked eye. People then get very skeptical (out of dissapointment) that space isn't like they thought it was gonna be. Obviously, looking through a telescope in your backyard shows nothing like what we see in pictures like the one referenced in this article.
With that said, the technology available in light gathering (in terms of sensitivity, especially in space where there is a lot less matter to block light) and the ability to apply filters to so many different wavelengths can really enhance interstellar phenomena. And actually, even the technology available to the amateur is nothing short of amazing. Just take a look the back of Sky and Telescope or Astronomy magazine to see amateur astrophotography.
I guess the important thing to keep in mind is that these pictures are enhanced. It doesn't mean the phenomena doesn't exist. Light is shooting out from the star, and it is passing clouds of interstellar medium that reflect that light, at all different wavelengths. People then just spend a ton of time, money, and computing power to enhance those images so that people can appreciate what goes on in our own backyard.
In the end, i guess you do have to trust that the base data itself is not "manufactured" by the government, but the data is certainly enhanced once its collected.
jeff
I was reading an informative article about the mistakes of Hubble yesterday.
It's time for Hubble-2 [google cache cause site down]
He seems agrees with the parent post but with a much longer explanation. The public has an emotional attachment to Hubble, but it costs too much, stares at the earth 50% of the time, has some communication problems, can only use one of it's instruments at a time and requires multiple billion dollar shuttle rescue/maintenance missions.
He even speculates that space telescopes could have been built for the price of Hubble.
As a Canadian I love looking at the pretty pictures you guys paid for. But the machine looks too much like a Stanley cup for my comfort.
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
And the 3 came from 2005-2002 (after re-reading the site, I should have chosen 2 (and hence 12 instead of 11) since the picture comes from 2004, but that doesn't change the explanation).
Imagine this: I'm blind and deaf, so the only way I can get communication from you is when you throw me a braille ball. Now, I know that all braille balls travel at 1 m/s, and I (somehow) know that you're 20,000 meters away (you're a really strong thrower), so when I catch your ball I know that you threw it 20,000 seconds ago. Now, there's a wall 14 meters from you that you simultaneously throw a second ball towards, and amazingly it reaches me after only 20,002 seconds! Well, since I know that it took 14 seconds for that ball to reach the wall, I subtract 14 from 20,002 to get 19,988. I now conclude that the wall is only 19,988 meters from me (i.e., it's 12 meters closer to me than you are), without needing to conclude that the ball has broken its "law" of traveling at 1 m/s.
I hope that helps.
Ben Hocking
Need a professional organizer?
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.
IIRC, the "flare" is diffraction from the secondary mirror supports, with the "shape" determined by the shape of the support (I think a cross in this case). A very long exposure makes it more obvious.
It's been a long time since optics, and not long enough since coffee.
These are the so-called "diffraction spikes." They come from the light of bright stars diffracting around the telescope's spider. The spider is the system of supports that holds the secondary mirror in place.
Sometimes you do see bleeding from saturated stars, but diffraction around the spider is usually the explanation.
I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.