Astronomy and Cosmology

WASHINGTON – APentagon-chartered report urges the United Statesto take the lead in developing space platforms capable of capturing sunlightand beaming electrical power to Earth. Space-based solar power, accordingto the report, has the potential to help the UnitedStates stave off climate change and avoid futureconflicts over oil by harnessing the Sun's power to provide an essentiallyinexhaustible supply of clean energy. The report, "Space-Based SolarPower as an Opportunity for Strategic Security," was undertaken by thePentagon's NationalSecurity Space Office this spring as a collaborative effort that reliedheavily on Internet discussions by more than 17…

http://www.guardian.co.uk/science/2007/apr/25/starsgalaxiesandplanets.spaceexploration 1.5 times the size of Earth and the right distance from its star to have liquid water

http://www.guardian.co.uk/space/article/0,14493,1660485,00.html Above is a link to some of the intel on the "Apophis" rock. More info can be gleaned from the previous thread, if one wants it, or by checking out the article. Now, everyone seems very excited about the idea of this asteroid passing close enough to see it (One my highschool science videos claimed it would pass closer than the moon). The problem is, it just might hit us. The effect might not be cataclysmic, but it would be kindasorta be like a kick in mother earth's testicles. This is a somewhat theoretical discussion. What would you do against this possible Armageddon? And whoever it was tha…

Guys here's an interesting article about what I'm sifting for. You know, phase transitions and state spaces, topology, etc http://online.kitp.ucsb.edu/online/qubit_c06/fradkin/pdf/Fradkin1_KITP.pdf I found a good page about curl and divergence too: http://www.math.gatech.edu/~carlen/2507/notes/vectorCalc/fcdensities.html

according to newton force of gravatition doesnot get effected by the medium between the two particles but in case of water as a medium what happenS?

Last year, I think it was, I read an article in the community rag about some professor or other who had set up a new office at one of the Tertiary institutions here in Auckland. This is, the story said, to assist with the international VLBA project, which NZ is expected to participate in by constructing part of the international array here (I think somewhere in the Sth Island). Does anyone know about this project? I haven't had a lot of luck chasing this one because I can't remember the name of the consortium.

http://in.news.yahoo.com/071005/139/6ll7d.html Heh, did we forget about it too, I thought one missing PHA would create a lot of buzz...

For the rest check out: http://www.spitzer.caltech.edu/Media/releases/ssc2007-16/release.shtml

What is the reason behind the twinkling of stars?Is it due to pollution or refraction of light?

movie taken by a NASA probe http://science.nasa.gov/headlines/y2007/01oct_encke.htm?list45222 Comet Encke was in near the sun and sporting quite a splendid tail while being observed by a NASA probe that was also in near the sun the sun occasionally has these Corona Mass Ejection (CME) eruptions which send plasma out at high speed and cause AURORA when they get to Earth and impinge on our polar atmosphere the probe got a movie of one of these CME ripping off Comet Encke tail. They play it slow at first so you can notice details and then they speed the movie up so you can see the tail being carried away downstream by the CME wind.

the science shows on directv speak of a asteriod/meteor that will hit earth is it real ? i am not speaking of any sort of mayan prophesy or anything like that. i do remember an identified mass in space that was said to be feared to collide with earth. what it is called i dont know. i believe it was supposed to collide with earth around 2010 or so. give or take a decade. i realize this could happen at any time however what does it mean to have seen one (science) that would threaten the human species as well as the earth as we know it ? i know its very bad to bring this up without having a name for the mass in space however ever since i have seen the document…

Hubble flow tells us the more distant a galaxy the faster it goes away or an other way to tell is the expansion is a function of distance. It is based on observation of the redshift and on the distance mesurement of galaxy. I thaught about it an other way: The more you go in the past, the faster the galaxy goes a way or the expansion is an inverse function of time. How can we decide which interpretation is the good one ?

http://arxiv.org/abs/gr-qc/9704009 Any thoughts on this idea? Just more Max Tegmark being crazy or what? I really like it

wen the big bang occurred as i understand it the universe was at one extremely small point i think they called it the Primordial Atom but then it blew it was small (compared to now) and grew well if the universe was a bubble expanding with all matter inside it what kept all the matter from going outside this "bubble" of a universe ??? its kind of hard for me to explain the question but i think i asked good enough to get good answers

Our office subscribes to Scientific American and I happened to notice an article by Max Tegmark on our bathroom floor: http://www.sciam.com/article.cfm?articleID=000F1EDD-B48A-1E90-8EA5809EC5880000 He insists there are cosmological arguments which necessitate the existence of various types of parallel universes. One type he describes sounds less like a "parallel universe" and more like the necessary properties of a closed universe, however he describes what he calls a "Type II" universe which sounds more like the Everett many-worlds interpretation. Can someone who actually studies this stuff opine?

is there a difference between the two or are they the same and if they are different what makes them different than one another??

i wanted to know that how are the nomenclature of the planets done?what is the procedure for it.

Cool huh? Check out the rest: http://www.spitzer.caltech.edu/Media/releases/ssc2007-14/release.shtml

http://arxiv.org/abs/0708.4013 Interesting...

I read the Wikipedia article about Metric Expansion (of the Universe) and had a few questions: 1) Has space ever been observed (in a lab or in deep space) to actually be reduced? Or is space only capable of expanding? 2) Is this space 'expanding' or is it being outright created? 3) Do scientists have a good idea of what causes this or do they simply observe it in space and shrug their shoulders, hoping to find out at some later point? Lastly, this isn't so much a question as an opinion, but it would seem that if the Metric Expansion explanation is correct, this has major consequences for science and even the future of technology. For starters, energ…

The MBR, I'm reliably informed, is light emanating from when the Universe was just 380,000 years old. We are now just picking up this light in the form of microwave radiation. However, surely when the light first started its journey the Universe was much, much, much smaller than it is today and of course, the matter that would one day make up our solar system and the detectors that see this radiation were part of it. How is it then that over 13 billion years later we can 'see' this light? Surely by this time the light from this distant era of the Universe would have long since past the position in the Universe that we now occupy. I know that I am probably…

Hi guys! Simple question, not much need to over-explain: What (if any) is the difference between an Astronomer and an Astrophysicist? Thanks! ~moo

If gravity is based on a higher mass = higher pull, then why does the earth pulls us so we dont lavitate, and the moon is a different experience... It has to be more than that... PS: I try to figure out how gravity works in order to progress with my theory about lavitation...

here is website for the "magic" collaboration, showing one of their dishes. they have an observatory in the Canary Isles. http://magic.mppmu.mpg.de/ recent news http://magic.mppmu.mpg.de/physics/recent/index.htm they observed gammaray flares from an AGN (active galactic nucleus) some half-billion LY away and found that the higher energy bunch was coming in with about a 4 minute delay, pointing to a fractional decrease in the speed the photons were traveling of 10^-14. That is "ten quadrillionths". It means some of the photons in the flare were moving ten quadrillionths slower than the rest. http://arxiv.org/abs/0708.2889 Probing Quantum Gravity using Photo…

What makes less dense things orbit denser things continuualy? Like if you get a bowling ball and a pingpong ball. You settle the bowling ball in the middle of the bed. Then you lightly toss the pingpongball and it'll orbit the bowling ball for awhile then itll get sucked in because it runs out of forward energy. What makes it so earth continuualy orbits earth and not get sucked into the Sun? -------- And how do dust clouds form in space. The one that makes galaxies. --------