Galaxy Definition and 528 Threads

How can we see the x-ray emission from the center of our galaxy? I thought that the intersteller dust extinguished practically all of the visible light from that direction, which is why we can't "see" the bulge. How then, can even shorter wavelength photons manage to get through? I thought...

Can anyone work out the probabality of intelligent life at around our current level exisiting within our galaxy.

several months back some PF people were discussing the finding of a z = 10 galaxy by a French team led by Roser Pello Now three Anglo-Saxons at the Imperial College have reluctantly expressed doubts: they have tried to find the reported Lyman Alpha line and did not see it. S. J...

Largest Galaxy: The central galaxy of the Abell 2029 galaxy cluster, 1,070 million light-years from Earth, has a major diameter of 5.6 million light years - 60 times the diameter of the Milky Way Galaxy. Reference: Guinness World Records 2000 - Millennium Edition

why aren't we spending more money on developing nuclear-powered rockets? an interesting article about nuclear rocket propulsion "...Nuclear-reactor rockets, like the ones that would be used in the Bimodal Nuclear Thermal Rocket, conduct nuclear fission reactions -- the same kind employed...

Would you please tell me what is in there ? I mean what substances are existing ? Where can i find out some information about this ? Thank you very much,

Our solar system is in the milky way galaxy. if you are told that in another galaxy a planet p has a circular orbit equal to that of the Earth's (that is they both have the same radius). the masses of the suns in the 2 galaxys are Se and Sp respectively and planet p completes its orbit in half...

thanks to MARCUS. this discussion started in S B and LQG, i thought i had better move to a more appropriate place. the recent discovery of a Z=10 galaxy, if confirmed means it was was formed when our universe was only 500MYs old. this paper discuses the discovery...

i don't understand how dark matter acts upon the rotation of a galaxy. galaxy rotation doesn't work the same way that solar system rotation does in that it's not a simple gradient of further planets rotate slower, right? nor is it further planets rotate faster, like a vinyl record...i take it...

I bought a nexstar 114gt a few months ago, and I have been unable to use the auto align features, which would allow me to use the tracking and goto features on the telescope. I am not certain if the telescope itself is flawed, or if I am simply doing something wrong. I sent two emails to...

Roser Pello and her colleagues at the MidiPyrenees observatory have reported finding a z=10 galaxy this galaxy is currently 31.5 billion light years from us and is receding from us at 2.3 times the speed of light for more details see "the most distant object thread" especially links...

This is my first post, so I am going to get straight into a double barreled question that has been bugging me for a while. (1) How long does it take for stars to conglomerate around a general loci, in order to form a proto-galaxy. ? I ask this in the light of the most recent Hubble images...

Dear Sir, Please Find the story at the link http://www.internationalreporter.net/scripts/headDetails.asp?id=108, which has a story ,also given under. This could be an eye opener to the scientific community. We definitely seek your response regarding this. Thanx.. Arif FARTHEST KNOWN...

Dear Sir, Please Find the story at the link http://www.internationalreporter.net/scripts/headDetails.asp?id=108 which has a story ,also given under. This could be an eye opener to the scientific community. We definitely seek your response regarding this. Thanx.. Arif FARTHEST...

I hadnt heard of GW recoil imparting velocity to a black hole. http://www.arxiv.org/astro-ph/0402056 "How Black Holes Get Their Kicks..." It's an article by three people, from Cornell, MIT, and Chicago. When two black holes spiral in and merge, linear momentum is carried off...

So, this doesn't fit the current model, right? http://heraldsun.news.com.au/common/story_page/0,5478,8344220%255E662,00.html Nasa: http://www.gsfc.nasa.gov/topstory/2004/0107filament.html

A newly released mosaic image from Hubble, with 4 billion pixels, covering a square of sky about 1/2o wide, with an angular resolution of 0.05", and a depth of 24 or 25 mag. "Not only does the GEMS study cover a large area at high resolution; it is also a three-dimensional map. Of the 60,000...

First of all let me say Hello! as this is my first post. I am a biologist, and have been reading over the very basics of SR for a little while and have a lot of questions on the implications of the theory. I had been asking my questions primarily at a different forum, one that wasn't...

I've been reading some books on Galactic Structures and Galactic Evolutions, evidence from rotation curves of stars near the centre of our Milky Way and also M31 suggest that there is a black hole in the centre. But is this true for all galaxies regardless of their Hubble Type? is there a...

Why is it easier to measure overall structure of Andromeda Galaxy than to measure Milky Way Galaxy?

"The nearest galaxy to our own Milky Way has been revealed. It is so close that the Milky Way is gradually consuming it by pulling in its stars. But it will be few billion years before it is entirely swallowed up. The previously unknown galaxy lies about 25,000 light years from Earth and...

Has anybody here read Douglas Adams' The Hitchhiker's Guide to the Galaxy ? I just started the series and am only about 56 pages into it. The whole book is hilarious so far. It's so full of puns, humor, and whim. Has anyone else noticed some subtle parodies to Asimov's Foundation trilogy? Like...

If there were many universes like there are solar systems in a galaxy and like there are many galaxies in the universe, What would you call it?

Greetings ! I thought you may like to know that our galaxy - the Milky Way, apparently has a small settelite galaxy at relativly close proximity. Here's the story: http://www.spacedaily.com/news/milkyway-02a.html Live long and prosper.

Greetings ! I just read Saint's post in the "moving galaxy" thread and though I knew the answer to that, I do not believe I have so far read somewhere an explanation for the existence of the galactic cluster sheets. So, is there a known and recognized reason ? (My guesses : 1. The...

I had come across some scientific articles that Galaxy is actually moving across the space! Is that movement due to initial explosion of the universe? The big-bang? When thing moves, it has energy 1/2M.V^2 , if the galaxy which is so huge is moving, from where does it get the kinetic...

"Skinny" galaxy harbors massive black hole at core http://www.berkeley.edu/news/media/releases/2003/04/10_skinny.shtml What kind of changes to our "rule of thumb" can we expect from this finding?

hi,was the formation of our galaxy inevitable after the BB or could there have been a different outcome, if the former is true then that implies that information or rules were stored pre BB, if the later is true what other outcome could arise. wolram.