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First Science From A Virtual Observatory
mindpixel writes "I first mentioned Virtual Observatories in my July 2000 Slashdot interview. Now, nearly four years later, Spacetelescope.org is reporting a European team has used the Astrophysical Virtual Observatory (AVO) to find 30 supermassive black holes that had previously escaped detection behind masking dust clouds. The identification of this large population of long-sought 'hidden' black holes is the first scientific discovery to emerge from a Virtual Observatory. The result suggests that astronomers may have underestimated the number of powerful supermassive black holes by as much as a factor of five."
It's a frickin' database!!
No, the ones detected were in the centre of galaxies...
Also the effects of their gravity are not invisible they have entire galaxies in their grasp.
Jeroen
Secure messaging: http://quickmsg.vreeken.net/
No. What you're talking about is the motions of distant galaxies.
What the article is talking about is powerful and extremely massive black holes at the centers of certain galaxies, whose centers are obscured by dust.
Using a technique of observing the same objects at widely different wavelengths and correlating the observations, spectra can be obtained, yielding information that implies the existence of the black holes.
This population had been theorized, but not observed until now.
HCG 50a = 2MASX J11170638+5455016
11h17m06.4s +54d55m02s
Good question, but no. You idea presupposes that there is a center to the universe, from which the galaxies (and the black holes contained therein) have expanded, much like shrapnel from an explosive. Think of it instead as being like points on a balloon as it expands; they're all getting further away from eachother, but none of them can lay claim to being at the center. Therefore there is no point at which one of them is 'outside' the others. Without that vantage point, there is no way to pull.
Allegedly real newspaper headline from 1998:
Man Struck by Lightning Faces Battery Charge
Grandparent is mistaken. Dark energy is just normal energy: it gets its name from a problem that astrophysicists have had since Einstein; if the Universe is expanding, and there is only so much matter and energy that we've accounted for (which, by itself, would cause a "big crunch"), what is causing the expansion?
Astrophysicists call the energy required for such an expansion "dark energy" not because its "evil", but because they can't see it (in the figurative sense).
http://chandra.harvard.edu/resources/faq/black_hol e/bhole-main.html
This will answer all of your questions about black holes.
more specifically, this one:
l e/bhole-40.html
http://chandra.harvard.edu/resources/faq/black_ho
Not to mention that practically every biology paper involving a molecular sequence includes a search against GenBank, a database of all publicly available sequences started in 1982. Database-based science is nothing new in biology, but we don't call it "virtual sequence hybridization" or some such thing, although database searches have replaced a lot of experimental approaches to sequence similarity measures.
The dark energy refered to is unusual because it implies a kind of antigravity. It isn't drawn into play to account for the fact that the universe is expanding, but rather to explain the recent observations that indicate that the rate of expansion is increasing.
It is related to Einstein's cosmological constant which Einstein regretted introducing because it was kind of a kludge to account for a supposed static universe.
Apparently there are cosmologists today who still regard it as a bit of a kludge, making the cosmological model convoluted like Ptolemy's model of the solar system. There was a recent Scientific American article that discussed this, but only a summary is available online.
Maybe you were confusing it with dark matter?
You are referring to dark matter: the "missing mass" problem. There isn't enough mass to account for the fact the universe is expanding (and apparently is nearly flat). Hence, there must be some form of matter we cannot see, i.e. dark matter.
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Dark energy is a second conundrum which does not depend on the mere fact the universe is expanding. It is a puzzle generated by the fact that the rate of expansion seems to be increasing! It's as if something is actively pushing space apart; since gravity grows weaker with distance the push becomes more and more important as the universe expands. Hence the "cosmological constant" -- it would provide a constant push that would initially be overwhelmed by gravity (so the expansion of the universe would begin to slow) but would remain constant everywhere regardless of distance and would thus overcome gravity over very large distances. The result? A universe that goes "bang," inflates rapidly, and then begins to slow down as space expands. Forward billions of years...and the slow expansion starts to speed up again, faster and faster until everything flies a p a r t . .
Make cheese not war 8:)
It's a search engine, for the most part.
I'm one of the programmers on the Virtual Solar Observatory. The poster I'm presenting today at the American Astronomical Society explains a little bit about what we're trying to accomplish.
The problem is that there are lots of places out there that are making recordings, but not all of the data are being shared with other researchers. Much of the time, it's because people don't know the data is even out there. For instance, if someone finds some odd reading out there, before they go and spend a lot of time on it, if they can compare the data to some other telescope reading at the same time, that's at a different location, they might be able to determine if it was an error on the instrument, as opposed to a legitimate event.
As instruments only point at a fixed region, if you find something on a wide angle picture, you can try to find out if someone else was pointing at the region of interest with a better resolution at that point in time.
Build it, and they will come^Hplain.