Astronomy and Cosmology

Hey I have a presentation due soon that is geared towards stars but my topic is black holes and some questions are hard to find information on because the questions are geared towards starts no bla ck holes. Here are the three questions I need help with: -What are the stages of a black hole? -what elements are black holes made of? -What do black holes create?(elements/forms of radiation) Any help would be greatly appreciated!! ---thanks GR

I'm doing a science project about controversy on black holes, and though any information on them in general would be appreciated, I'd like to focus more on whether or not one could ever engulf our galaxy and virtually "eat" it or not, and what might happen if it did. Any help on this would be greatly appreciated!

FWIW = For What Its Worth FWIW, I did a treatment called "Collapsing Universe?" in Oct. 2003, and by means outside my control (it got picked up as a blog) it has gotten a number of unaccountably high search engines ratings.FWIW http://physics.about.com/b/a/034824.htm Its non-professional presentation not withstanding, the 'model' presented made a serious prediction. To whit: "In our matter cone this secondary center of gravity might be seen in the conjectured "Great Attractor" in the area of Virgo Cluster." There is a reasonable possibility that CMB data may support the above prediction. The 2003 treatment is in need of a serious restatement, and I wo…

Hi -- sorry if these are stupid easy questions, but... what keeps the earth from falling into the sun? Also, does anyone know if the earth spins around its axis in the same direction as it orbits the sun, or the opposite?

kepler third law is being used all the time to discover exoplanets of which over a hundred are known I've met Geoff Marcy who discovered many of those and was among the very first to find an exoplanet by the wobble method and he wrote in a NYT interview that when he first detected an exoplanet he felt the spirit of Kepler was right there when you infer a planet's presence from watching the star wobble, kepler is right at your elbow telling you what to look for and how to interpret Kepler is great and his finding the third law in 1618 was approximately the beginning of math-based science Kepler wrote that he first discovered the third law on 8 March 1618 and …

We will make some simplifying assumptions for this new planetary system: the orbit of the planet is circular (e = 0) the mass of the star is 1 solar mass the mass of the planet is much, much less that of the star we are viewing the system nearly edge on we express everything in terms of the mass and period of Jupiter We make these assumptions to simplify the equations we have to use for determining the mass of the planet. The equation we must use is: Mass of planet = (P/12)^(1/3) x (K/13) x Mass of jupiter P is orbiting time, K is the amplitude of radial velocity change. P should be expressed in years (or fraction of a year),…

hi every1~ This question came up during a discussion in my physics class about the doopler effect and how it implies to the universe. The question was how would be the universe like without any planets, and other physical phenomena. Since that time I've been wondering about this question, and haven't came up to an effective answer. But, to the extent of my limited understanding, I suspect the universe would be a "black hole". What do you guys think?

We're doomed!

Hi, Im new on this forum and I just want to ask a question that I asked in class and my teacher wants me to solve, and I guess this forum is full of clever people . I was wondering how far up a bullet would have to be up in the air, for it to burn up before it reaches the ground. In advance, thanks for the help.

Hello All, I joined SFN a while back, but I have not been too active, I intend to change that. Anyway, I am only thirteen. I have been striving for years to discover a field of science to go into, and I believe, it will be Astrophysics. I have information on this field, and I have been finding as much information as I can. After awhile, I thought that maybe you people could help me. What exactly is astrophysics, in your own words if possible? Can anybody give me some links, maybe the titles of some good books? Thank You, Michael Kovich

http://www.space.com/scienceastronomy/mystery_monday_040524.html I was reading an article about the size of the universe & got very confused. It explained it thus: My problem is this: A star produces X number of photons along a hypothetical straight line in one "year". The first photon is a light-year away from the sun, the last one is just coming out of the sun. According to the quote above, the line has now stretched 1,000 times it's original length. Since there are still the same number of photons along that line, wouldn't the light be 1,000 times "weaker" to our eyes? What piece is my layman's brain missing?

HI, i was wondering if it was possible to propel rockets with rocket fuel till it reaches outer space and then propel it with solar power ...if this was possible the rockets would be able to carry us to other galaxies(if there r people who dare to travel).this was buggin me for a long time.....

I'm a seventeen-year-old student in high school who wants to be an astronomer. Can you hook me up with a good, affordable college that would impress Nasa? Thanks.

http://en.wikipedia.org/wiki/Fecund_universes Yeah, this idea is just so awesome, and finally I know the proper term with which to describe it!

Alpha Centauri B??? I'm curious as to why Alpha Centauri A is not included in this list since it is the same spectral type as our sun. B is a K1 class star, cooler than our sun, while A is a G2 class star, the same as our sun. Both stars are thought to be able to sustain planets with in the orbit of Jupiter; so why would they pick B over A? http://msnbc.msn.com/id/11427824/ For referance... 1. http://en.wikipedia.org/wiki/Alpha_Centauri 2. Isaac Asimov's "Alpha Centauri" Why Edited due to poor English.

The last I remember hearing, Andromeda will collide with the Milky Way in about 300 billion years. Has anything else been said with this? Is the "supermassive blackhole" theory still viable?

we werent satisfied with what we see in our science books about the universe and its creation and as such we made up our own theory. This is how it goes: during the big bang some particles where made and throw off into space before the others. the ones thrown earlier where thrown below or at the speed of light, the ones thrown later where thrown over the speed of light. the earlier ones are what we now call the visible part of the universe since light can get up to it and expose it. but the later ones are called the invisible universe since light cant meet up with them. the invisible universe are what we know today to be the "missing mass", which will one day get vi…

Well, if physics reporting is anything like climate science reporting, this article is chock full of overgeneralizations and inaccuracies. Anyone care to help me derive a little meaning from it? Sounds to me like they've discovered some kind of weird pattern in the CMBR http://news.independent.co.uk/world/science_technology/article342351.ece

Well , there are very few chances that I can be right. I spotted an unidentified(according to me) object in the sky last night.It was 1. Flying very close to earth that I can easily view its design and structure. So It cannot be an aeroplane or rocket in a sense 2. Some may use illuminated kites, but it cannot be that because a total of three different lights were coming out of it .One red other green or yellow and the third was twinkling. 3.Moeover it was flying at a fairly constant speed I just wanted to know what are the speculations or statutory conditions to be declared it as an UFO and the other things for which I may have misinterpreted for it…

after reading some of the thread about gravity and the edge of the universe etc... a thought occured to me when I made a post that gravitity only reduces over distance but never actualy becomes Zero, there`s some that beleive the universe has an "edge" like a border. wouldn`t these 2 ideas be in conflict at all? I`m sure we all remember the old demonstration about Curved space where a large ball is placed in the middle of a rubber sheet, and then a smaller ball that would ordinarily pass along the sheet in a straight line spirals gradualy towards the large oject or takes a curved path. now bearing this in mind, if the sheet were infinately large even at the very ed…

Why is it assumed that the pre and post-inflationary epoch BB event expanded 'isometrically', when most other energenic mass expulsions take the form of 'jets' or 'pulses'? I have heard that an isometric expansion is assumed because our mathematical 'toolkit' can only express this type of expansion. Is this true? aguy2

dark matter is a complex negative energy. It lies at a parallel opposite of the actual matter we know i.e earth for instance. earth has a tiny mass in comparison to the universe, as does its counterpart dark matter, its opposite. So using my equasion one can work out its exact location and speed, energy, time taken to anti gravitise against the earth. Anti gravitation is a theory of mine which includes anti pressures of the field it is within. Therefore the position of the earth is the negative position of its dark matter counter part, dark matter is invisible as it has no weight and therefore no visibility for detection. But using my equasions one can see that it is ther…

I've been studying Misner, Thorne, and Wheeler's Gravitation and a thought had occurred to me: if black holes had angular momentum, why wouldn't this cause torsion in spacetime? If this is true, wouldn't we need to reject Einstein's field equation and "get" a "new one"? Maybe I jumped to the conclusion too soon thinking "Aha, angular momentum of a black hole affects spacetime, thus spacetime would be 'twisted' or at least victim of some sort of torsion." I was also considering this in terms of quantized spacetime, which may have caused the problem(!).

So, I read that at time = 10 billionths of a second after the big bang, the temperature was "billions of billions of billions" of degrees celcius. Now, from what I've learnt in chemistry, heat can only be passed on to other objects, so if there are two objects out in space at 100 degrees touching each other, they will remain at 100 until they touch another piece of matter that is higher/lower than 100degrees? Well, why when every single particle at those early stages of the universe are at roughly "billions of billions of billions" of degrees celcius, the temperature now on earth is only 30 degrees. the temperature of the hottest suns are only in the millions of …

Who thinks we are wasting time on the space exploration side of things, to many unmanned missions. I thought by now the governments would of started to construct a spaceship in space because then the size wouldnt be an issue because you wouldnt have to lauch it through our atmosphere. What they could do is build a massive city like ship capable of accomadating up to 500 maybe more ppl easily. Oxygen can be sustained by a huge ecosphere in the center of the ship containing all forms of plantlife which is rich in oxygen output and carbon dioxide input. Which would be grow and cared for by computerised sprinklers supplying recycled human water before the fresh supply. …