Rookie Question Thread: Space Science and Astronomy

[votefornimitz]

Have a burning question that needs to be answered, but want it to get paid attention to without being labled as trolling. Post it here and we'll answer it ASAP. <div class="Discussion_UserSignature"> <span style="color:#993366">In the event of a full scale nuclear war or NEO impact event, there are two categories of underground shelters available to the public, distinguished by depth underground: bunkers and graves...</span> </div>

 

[maxtheknife]

Oh, is this the thread where you answer questions you haven't answered from other threads, Vote?

 

[rodrunner79]

Ok, I have a question, or should I say questions..... If the universe began with nothing (nothing as in dark nothing). Then what ignited the first stars to burn? Is it collision with other stars? I mean gas cannot just ignite itself. And let's say a star is forming, when it forms is it already burning? Or does something ignite it to burn? If so, what ignite's it?

 

[vogon13]

I am picturing some poor technician holding a cigarette lighter trying to detonate Mike, the United States first true hydrogen bomb.<br /><br />Seriously, to ignite fusion reations in Hydrogen, there is an equation (which I don't have handy) which is rather simple. If you multiply the pressure (in certain units) by the temperature (in certain units) and get a product greater than a certain value (which I don't recall) the Hydrogen will fuse and liberate energy.<br /><br />Handy thing to know when building Hydrogen bombs, or lighting off a star.<br /><br />That mankind can understand Hydrogen fusion in a star, and taking that knowledge, can build and successfully detonate a Hydrogen bomb should make it clear to you that this stuff is all <i>proven facts</i>.<br /><br />BTW, I have never seen any one take the position that all the Hydrogen bombs detonated were all just a big hoax.<br /><br />But I suppose it is just a matter of time.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[thermionic]

>>BTW, I have never seen any one take the position that all the Hydrogen bombs detonated were all just a big hoax. <br /><br />That's a good idea, Vog! I think I'll swing by Phenomena and promote the concept.<br /><br />Regarding stars igniting, as Vogon explained there is a relationship between pressure and temperature called the ideal gas law:<br /><br /> PV = nRT<br /><br />P = pressure<br />V = Volume<br />n = amount, in numbers of paricles <br />R = Universal Gas constant<br />T = temperature<br /><br />Shortly after the BB, a lot of protons coalesced from the quark soup. A proton is a hydrogen nucleus. So think of the early universe as a gas of protons, neutrons, & electrons, being excited by photons. Small variations in density lead to local thick regions. These are proto-stars. Once density increases in an area, gravity pulls the protons yet closer together in a feedback cycle. Temperature goes up, and eventually the protons & neutrons have enough energy that when they collide, they can fuse. The same process is still going on, creating new stars, even now.<br /><br />The initial density variations leading to the symmetry breaking are a puzzle though. This can still be barely seen as tiny variation in the cosmic background radiation, so we know that the big bang was not completely uniform.<br /><br />So my burning question is, what produced the non-uniformity of the earliest universe?