Astronomy and Cosmology

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Thanks.

Is it east to west in the in the dark belts and west to east in the pale zones?

Hey its my first post,so be nice. Have anybody here heard of 'world jump day'. The guy claims that iff 600 milion people jump simultaneously the worlds orbit will change ..... What's your opinion? World Jump Day

http://www.space.com/scienceastronomy/050401_first_extrasolarplanet_pic.html they have been watching it since 1999 and the separation from the star has not changed at all so finally today they say it is "confirmed" we have all seen photos in the past few years of things that PROBABLY are planets, next to their stars, but those things they are still watching to see if they move together with the star for long enough for them to be sure they are planets and not just some other object in the background this "confirmed" planet at GQ Lupi is not interesting as a place to live. it is far from its star, 3 times the distance of sun to Neptune, and it is ve…

Help please!

Help again please!

I want to know if the photons which the sun emits, are responsible for the path of earth's orbit around it. The sun is for certain emitting photons, and they must leave the sun at a speed 299792458 meters per second relative to the sun. They are emitted in many directions, roughly in a spherical shape. So the region of space surrounding our massive sun, is filled with the photons which the sun is sending out. So could these photons be solely responsible for the orbital path's of the planets? Thank you PS: If the answer is yes, then the speed of gravity is c.

http://antwrp.gsfc.nasa.gov/apod/ap050401.html APOD obviously having a little fun with the date.

Mass of moon is 1/81 Earth's mass Gravity of moon is 1/6 Earth's gravity WHY!

To what extent do the CMB and the Hubble expansion define a preffered reference frame?

In another thread, which is now closed, swansont said this:

Please answer the following question only if you are sure of the answer 'What is the speed of gravity in miles per second?...us.2u

see this short movie made from timelapse shots of Crab http://chandra.harvard.edu/photo/2002/0052/combinedmovie_sm.mov here are other movies of Crab http://chandra.harvard.edu/photo/2002/0052/movies.html advise you select the low resolution version so it takes less time to download and let the download happen in the background while u do something else. it takes several minutes but then u can come back and play it "This movie shows dynamic rings, wisps and jets of matter and antimatter around the pulsar in the Crab Nebula as observed in X-ray light by Chandra (left, blue) and optical light by Hubble (right, red)."

Hi, I was wondering if anyone knew how cold complete coldness is? Is it measurable? eg its 36 degrees celsius where i'm at at the moment. If I was to zoom straight up beyond the atmosphere, it would be pretty cold but the temperature would still be affected by the sun. If I was then to zoom off out into space well beyond all the stars created by the big bang to a totally isolated spot that is not touched by any light or energy, so you cant see any stars ect, complete black. How cold would it be? Is this known? Thanks for any info

according to the standard picture space started out full of hot plasma and about 380,000 years from the start of expansion it cooled enough to become largely transparent neutral gas. the CMB dates from that moment when the material filling space became transparent. the photons from that moment are still traveling [side comment: if space were finite (analogous to the surface of a balloon) and small enough then some of them might have been around once already and be coming around again. but I dont think that's very likely. even if it is finite most astronomers think space is too large for that to have happened] anyway all space is filled with the CMB light which…

Is time of the same measure throughout our universe & beyond? Or are there different sorts of measures? I only understand time as I was brought up with it & take it for granted,but is our time the same measure as for everywhere else?....us.2u

http://www.metaresearch.org/cosmology/speed_of_gravity.asp I would love to know if this could be possible also I remember in my youth riding a pedal cycle at night seemed to be easier than riding in daylight & sound seems to travel further when it's dark; is this just imaginable or maybe light does slow things down slightly? And if gravitity is faster than light can we somehow store it for space tr avel?...us.2u

so far there are only 2 theories of how the universe will 'end' 1- The big crunch: the gravity in the universe is so powerful that over-powers the expanding universe and it all comes back to one place and eventually we have a reverse-big-bang 2- The Big Freeze: the universe will continue to expand and all stars will eventually burn out and the universe will become dark, frozen, and time will have practically stopped. do i have this info right? wrong? close? Please add-on or correct this.

Before we get started I want to say i'm just a 3rd year HS student here to learn. Now onward. I cant remember where i heard this but, i heard a multiverse my exsit. I'd just like to here what everyone thought on that

Space is not my strong point so any answers are appreciated. There's a question that I have been pondering about. I really have no idea if this has been talked over about somewhere but at least the recent threads didn't seem to exactly concentrate on this so here it goes: If we suppose that empty space is infinite (our universe is just the part of space where matter has "expanded" since Big Bang). Couldn't this mean that after the point where "Big Bang matter" ends is reached and went past of, through the empty space, there comes another universe originating from another Big Bang. Let us further assume that these new universes where the like of ours. Couldn't this me…

hey..im currently working on a big research papaer talking bout the shape of the universe..i jus started and im alreayd confused..it seems that ther are three posibilities for the shape and that the universe is flat.what does this mean? flat would mean having a single flat plane..but how is that possible when space time actually curves..i mean isnt the universe have depth to it? how can it simply be flat..please help!

Looking at the Friedman solution for a fluid with a given pressure and energy density, we have: [math]H^2 = \left(\frac{\dot{a}}{a}\right)^2 = \frac{8 \pi G}{3}\rho + \frac{\Lambda}{3} - \frac{k}{a^2}[/math] Would someone mind walking me through how we arrive at a? Rev Prez

The Pioneer 10 and Pioneer 11 spacecraft, the ones which are mysteriously slowing down... http://archives.cnn.com/2001/TECH/space/05/21/gravity.mystery/ Anyway, I was at the Mill Hill Observatory (I got to use the Radcliffe telescope: http://www.ulo.ucl.ac.uk/telescopes/radcliffe/ or image here: http://www.ulo.ucl.ac.uk/images/ulo_photos/rad_modern.jpg it's the only time it has ever been open to public (it was open because of national science week)).... back to the topic!... I was talking to a PhD astronomy/cosmolgy guy and asked him about what he thought was the 'mysterious force' acting on the Pioneers, he reckoned, off the top of his head, either mathematics error…

I've heard this term, but am unclear on it's exact definition. I think it implies that the entire universe as we know it is just one "volume" inside of a larger universe. Is that an even remotely accurate definition?