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Kullat Nunu
2004-May-14, 04:18 PM
A powerful and independent method was used to probe dark energy using NASA's Chandra X-ray Observatory. The results on cosmic acceleration provide clues about the nature of dark energy and the fate of the universe.

Team leaders will present findings at a Space Science Update (SSU) at 1 p.m. EDT, May 18, 2004. It is in the Webb Auditorium, NASA Headquarters, 300 E St. SW, Washington.

Panelists:
-- Dr. Steve Allen, astrophysicist, Institute of Astronomy, Cambridge, U.K.
-- Dr. Andy Fabian, professor, Institute of Astronomy, Cambridge, U.K.
-- Dr. Kim Weaver, astrophysicist, Goddard Space Flight Center, Greenbelt, Md.
-- Dr. Michael Turner, assistant director for mathematical and physics sciences, National Science Foundation, Arlington, Va.
-- Dr. Paul Hertz, Senior Scientist for Astronomy and Physics, Office of Space Science, NASA Headquarters, Washington, Panel Moderator.

NASA TV will carry the SSU live, with two-way question-and-answer capability for reporters at participating agency centers, available on AMC-9, transponder 9C, C-Band, located at 85 degrees west longitude. The frequency is 3880.0 MHz. Polarization is vertical, and audio is monaural at 6.80 MHz. To listen to the SSU, call: 321/867-1220/1240/1260. The update will be webcast live at:
http://www.nasa.gov

Any idea what that method might be?

Kullat Nunu
2004-May-18, 03:00 PM
Let's not forget this...

George
2004-May-18, 04:22 PM
Any idea what that method might be?

Do observed x-rays, which have been red shifted, provide better data regarding the motions of distant galaxies?

I look forward to the reports as I do not have NASA tv. :cry:

Kullat Nunu
2004-May-18, 04:43 PM
I look forward to the reports as I do not have NASA tv. :cry:

Don't you have an Internet connection?

NASA TV (http://www.nasa.gov/multimedia/nasatv/index.html) via the Internet.

Kullat Nunu
2004-May-18, 05:25 PM
Chandra press release (http://chandra.harvard.edu/photo/2004/darkenergy/) is now online.

George
2004-May-18, 08:05 PM
I look forward to the reports as I do not have NASA tv. :cry:

Don't you have an Internet connection?

NASA TV (http://www.nasa.gov/multimedia/nasatv/index.html) via the Internet.

Thanks, I have it now. (Assumed it was a cable tv option :roll: )

George
2004-May-18, 08:21 PM
Chandra press release (http://chandra.harvard.edu/photo/2004/darkenergy/) is now online.


Because galaxy clusters are the largest bound structures in the Universe, they are thought to represent a fair sample of the matter content in the universe. If so, the ratio of hot gas and dark matter should be the same for every cluster. Using this assumption, the distance scale can be adjusted to determine which one fits the data best. These distances show that the expansion of the Universe was first decelerating and then began to accelerate about six billion years ago.

Anyone wanta splain? Distance and relative motion are the parameters to acquire in order to reveal expansion rates, right? Is the angular size of the hot gas a distance determinator? Why the dark matter ratio assumption?

Ari Jokimaki
2004-May-19, 05:31 AM
Inflation, deceleration, acceleration... Who is supposed to be handling the accelerator pedal?


...the ratio of hot gas and dark matter should be the same for every cluster.

Isn't this rather weak assumption? I mean we don't even know what dark matter is.

George
2004-May-19, 03:14 PM
According to the San Antonio paper....


Scientists reported Tuesday they found new evidence of a "dark energy" that's pushing the universe apart and someday could rip up the galaxies and even the atoms we're made of.

Unfortunately, this is a fair reflection of the Chandra article. This point was at the end of the NASA news but at the beginning, no surprise, of the papers. [Should I not make mention of the preposition the papers sentence ends in? Obviously, not me]

However, if the Higgs field theory is validated, then the jerk and the acceleration will quit once it falls to it's lowest potential. Right?

Spaceman Spiff
2004-May-19, 07:12 PM
The science paper appears here (http://arxiv.org/abs/astro-ph/0405340).

George
2004-May-25, 04:22 PM
Inflation, deceleration, acceleration... Who is supposed to be handling the accelerator pedal?


...the ratio of hot gas and dark matter should be the same for every cluster.

Isn't this rather weak assumption? I mean we don't even know what dark matter is.

Who wants to suggest a black hole corelation? From... here (http://science.nasa.gov/headlines/y2003/09sep_blackholesounds.htm)


...This forced astronomers to invent several different ways to explain how gas contained in clusters remained hot. None of them were satisfactory.

Black hole sound waves, however, might do the trick.
Therefore, singing blackholes are a function of dark matter, right. #-o :wink: (just kiddin)

I still don't understand much of any of it, however.

ToSeek
2004-Jun-02, 04:14 PM
ABC News article:Cosmos at Full Throttle (http://abcnews.go.com/sections/scitech/CSM/dark_matter_040601.html)

George
2004-Jun-03, 12:16 AM
ABC News article:Cosmos at Full Throttle (http://abcnews.go.com/sections/scitech/CSM/dark_matter_040601.html)


Taken together, the X-ray, supernova, and microwave-survey studies represent "extraordinary evidence" for dark energy, the University of Chicago's Turner said at a briefing last week.
The results all seem to agree. Impressive as more and more light is shed on dark energy. (Mr. Higgs? #-o )

Manchurian Taikonaut
2004-Nov-29, 03:26 PM
ABC News article:Cosmos at Full Throttle (http://abcnews.go.com/sections/scitech/CSM/dark_matter_040601.html)


Taken together, the X-ray, supernova, and microwave-survey studies represent "extraordinary evidence" for dark energy, the University of Chicago's Turner said at a briefing last week.
The results all seem to agree. Impressive as more and more light is shed on dark energy. (Mr. Higgs? #-o )

more info from Chandra, not much on dark energy though

http://www.innovations-report.de/html/berichte/physik_astronomie/bericht-36766.html

NASA’s Chandra X-ray Observatory has obtained definitive evidence that a distant quasar formed less than a billion years after the big bang contains a fully-grown supermassive black hole generating energy at the rate of twenty trillion suns.


existence of such massive black holes at this early epoch of the Universe challenges current theories

http://www.spaceflightnow.com/news/n0411/28blackhole/

observed the Quasar SDSSp J1030 at a distance of 12.8 billion light years

Skyfire
2004-Nov-29, 03:48 PM
A powerful and independent method was used to probe dark energy using NASA's Chandra X-ray Observatory. The results on cosmic acceleration provide clues about the nature of dark energy and the fate of the universe.

<SNIP> ...lots of names....

NASA TV will ..........



SO...... did that dark energy show any stars?... And NASA TV will show.... pictures with C's on them..?? .... OH SORRY! Wrong forum..... :lol: