Astronomy and Cosmology

Planets are much dimmer than stars. Perhaps, then, you could do a "Hubble Deep Field" type, Long Duration image, of targeted star systems ? Blocking the light, from the central star, by standard means ("artificial eclipses"), such a "Planet-Finder Deep Field" might image many dim planets, perhaps as "arc-like" smears across the image, from the light accumulated over many days, weeks, or even months. Moreover, imagine training an "phalanx" of telescopes, each observing a different EM spectrum, at the same star system. Then, you could create, in composite, an "all spectrum telescope", which would image the target star system in everything from Radio to X-Ray (say). …

i was reading in my astronomy magazine that scientists have discovered a new type of supernova that was thought only theoretically possible but a 2002 supernova didn't fit the stereotype (white dwarf exploding or the collapse of a highly massive star) but this supernova is relatively faint, quick and doesn't have the scattering of elements that other supernovas produce. and there is other info but it doesn't relate to my question, would it be possible that some of these supernovas that're weaker that regular ones have happened further than 13.7B light years away but produced a light dim enough to not reach the reaches of our sattellites? thus leaving our belief that our u…

The redshift of light might not be related to scale factor like 1+ z = a(1)/a(2) as traditionally thought but as 1+z = [a(1)/a(2)]^2 ........................(1) This leads to a luminosity distance of c/H*(1+z)(sqrt(1+z) -1)..........(2) , with H half the traditional value, and gives a very good match to supernovae data without dark energy (for small z, d=c/2H*z so matches observations). The WMAP value for omeg(matter) of 0.25 comes about because omega = rho/rho(crit) and rho(crit) = 3H^2/8*pi*G and the value used for H is twice the real one. ---------------------------------------------------- The reason for (1) is not known for the purposes of this post…

Can anyone tell me how close to reality this bit of information is: --- The distance between the Earth and Moon is 108 times the diameter of the Moon The distance between the Earth and Sun is 108 times the diameter of the Sun The diameter of the Sun is 108 times the diameter of the Earth --- Appreciate your help...

the sun is a powerful star it gives us life without the sun and other stars there would be nothing in existance we and all matter are made up of stars freaky huh:eek: ===================================== the sun is not a big star there are bigger stars like rigel alpha swafefe and swafefe they have funny names but they are not funny in size they are over one thousand times the size of the sun

about where the universe starts and ends when did it come to the existance it hurts your head to think about it if the universe never started how did it get here if the universe is infinite where did it start in the first place:confused:i think since it never started it will never end who knows the future only god knows . feel free to post your comments this is juice from south texas

I have been wondering what the big mystery is regarding super massive black holes at the centers of galaxies. I was watching a documentary last night where cosmologists kept referring to the finding as a "mystery". What confuses me is that I always saw this as a given... though, for very uncomplicated reasons. Since galaxies have a center of mass I would assume that the galaxies develop somewhat similar to a solar system, with the bulk of the central mass being close enough together that over time it all was pulled together. The sheer mass of the matter was creating a black hole. (speaking of which: would a super massive black hole develop without burning it'…

Everytime I get into this subject I get confused. All these [math]\Omega_j[/math] and [math]\Lambda_k[/math]. Hmm...now, where was I? Oh here, let us take the latest WMAP-data. Maybe I got some decimals wrong (disregard that), but let us assume a density parameter as [math] \Omega_{tot}=1.003 \pm 0.010[/math] I'm a bit drunk atm, , but [math]\Omega_{tot}[/math] is a sum of different ratios (density ratios), also including a possible cosmological constant - [math]\Lambda_{something}[/math]? Now, assume, hypotetically, that [math]\Omega_{tot}=1.0000000...[/math]. As I get it, that only implies that the universe will expand on and on. However, the universe CAN st…

We know that, due to the presences of granite on the Venusian surface that there were oceans on Venus. Now, how deep were they? It it possible, from the mass of the atmosphere, to determine how much water was on Venus before it evaporated away two billion years ago?

According to the video The Shape of Space (VHS), a 3D hyper-torus can be represented, by a "fundamental unit" cube of space, which is "glued" to itself, such that each pair of opposite sides are made to be mathematically contiguous & identical. Could you not, then, by suitable manipulations of the size, shape, and "boundary conditions", of computer simulations, simulate various topologies for spacetime (hyper-torus, hyper-sphere, etc) ?

Why is it that when an meteoroid reaches the Earth it's called a meteorite but when an asteroid reaches the Earth it's still called an asteroid?

A short film we've posted to give a feel about what an astronomer does on an observing trip...

They just started up 3-30-10 to 3 times the previous power record. When will we hear some news? They keep repeating their mantras about finding the God Particle Higgs boson, a scientific revolution. And just what else is inside matter? Higher dimensions? It seems like it will take a long time before anything new is revealed. http://www.huffingtonpost.com/2010/0..._n_518196.html

These are drawings that Galileo made of the moon after turning his newly built telescope on it. http://outreach.atnf.csiro.au/education/senior/astrophysics/galileo.html Why did he draw such a poor likeness? This is not how the moon looks, either to the naked eye, or through a telescope. There is no big mountain range down the middle, with a giant round crater near the bottom. Is it because he was not used to a telescopic view? Or was there an agenda that distorted his view, or his drawing? Why not show the moon as it is? What was going on here?

see the sun is not what kids think see the image so if you have kids that are old enough to understand but still thinks the sun looks like thissun then you should show them picture 1

well for starters dark matter is the matter that takes the space where regular matter is not. Get what i am saying y'all.Dark matter is a theory and theories can be disproved what if there is no such thing as dark matter what if there can be space without matter or what if there is regular matter that we dont know is there thats all i am saying feel free to post your comments on dark matter here

I think that there is another planet with life on it do you? if you do where how long will it take us to get there:confused: will they be mean or nice will they have a short temper:mad: think about it will we be able to travel out of our solar system maybe 2 years maybe 200 maybe even 2000 years but i strongly think that we will be able to travel really far out there i also think we will be able to time travel post your opinions that would be very great y'all

The universe is a wonderful place to explore yet we can not explore the whole thing. We cant even get out of our solar system. I think before humankind dies out we will be able to travel out beyond pluto.Ifyou are reading this you should think what i am talking about i am pretty sure that we will get out of this solar system. You might be thinking that that would take a miracle but the real miricle here would if we get out of this solar system in our lifetimes. Feel free to reply.

As simpleton, I can not reach an understanding from numbers. I only take for granted that, which receives a very large majority of agreement. I imagine und very much hope that some of the many incredibly smart and imaginative people on this site are able to see the possibility and investigate in this and all possible directions. I know I need lots of help and appreciate all the help I can get from anyone. I do not mean in any way to state that, this is it, just that it might be possible. There are so many possibilities “almost right theories and general agreement” that none of them so far is the final word. I believe things will only be right if most everybody can agree. …

i just found out about this theory, and i find it very interesting. Does anyone have any information about it? eventually the universe will stop expanding and rapidly decrease in size, and eventually a 'reverse-big-bang' will happen?

The milky way galaxy is our home it is where our earth is. The milky way is 100,000 light years across and our closest neighbor the andromeda galaxy ...well i don't know how big that galaxy is but as we all know we are all part of a place called the cosmos.The cosmos has millions of galaxies, none of my other 5th grade classmates know that there is another galaxy in the universe, that sometimes scares me but thats why i dont sit by any of those kind of kids ...well thats all...i guess ***TEXAS ROCKS Y'ALL***

Life is a precios value are there life on other planets yes no maybe if you think there is life on other planets or if you dont post some replies y'all this is juice from south texas

these are the galaxies of the UNIVERSE the url to the website is http://images.google.com/images?hl=en&q=galaxy+images&um=1&ei=jpivs5q00i078gam1dihcw&sa=xeoi=image result group&ct=title&resnum=1&ved=ocbeqsaqwaa

this following picture is an artists point of view of the death of the universe. some other pictures are on this url http://images.google.com/images?hl=en&q=the+universe+images&um=1&ie=utf-8&ie=olqvs5gvcsl98ablm-i5dw&sa=x&oi=image result group&ct=title&resnum=1&ved=ocabqsaqwaa on one of these replies you will get the picture on the death of the universe... i hope Merged post follows: Consecutive posts merged Merged post follows: Consecutive posts mergedWell ...just go to the url and you will find the picture that says universe to the left to the picture to the abyss

I'm working on an astronomy project, and I need a heliocentric ephemeris app download for the planets. I'm cautious of not well-known software, so I'd much prefer a trusted app ... definitely not one for astrology. I'm also on a shoe string budget, so getting it for free is pretty much necessary. I'm aware that I may be asking too much. Thanks!