Remember that Universe You were Looking For?

[3113]

They found it!

First, a bit of background. Galaxies are filled with hydrogen gas, and that gas is a major component of the clouds that collapse to form stars. When that happens, the hot stars ionize the gas: the flood of ultraviolet light strips the electron away from the proton, freeing both. If the electron gets near the proton again, they can recombine. Because of quantum mechanics, the electron can only exists in certain energy states, which are a bit like steps in a staircase. You can jump from the third step down to the second, but there is no second-and-a-halfth step.

So it is with electrons. It used to be taught that this levels were like orbits, but that’s not a great analogy; the staircase is better. So if the electron is on the second level and drops to the first, it gives off energy in the form of light (just like when you step down you lose a bit of energy too, and it takes energy to go up a step). For the 2 to 1 step in hydrogen, the photon emitted is in the ultraviolet, and has a special name: ***** alpha.

Ionized hydrogen gas clouds tend to blast out lots of ***** alpha. This makes it a good way to search for distant star forming regions; just look for that wonderful wavelength of light associated with the 2 – 1 transition of hydrogen. As it happens, we know that when the Universe was young, about a quarter the age it is now, star formation was going on at a much higher rate on average than it does now. So astronomers figured, hey, why not do searches for distant galaxies using ***** alpha? They should pump it out, and make them easy to see.

So they looked. And to their surprise, they only found about 10% of the galaxies they predicted they should! Uh oh. This has been a problem for some time. But it’s not anymore: a recent experiment by astronomers shows that the galaxies are there, but they’re hidden! What they did is look in one part of the sky, using the GOODS South field trying to find ***** alpha emitting galaxies. Then they looked at the same region, but looked instead for H alpha, the line emitted when an electron jumps down from the third energy level to the second. And guess what they found: tons of galaxies!

The problem, they surmised, is that the galaxies are actually there and emitting ***** alpha. But before that ultraviolet light can get out of one of those galaxies, it gets reabsorbed by gas inside the galaxy itself. We never see it. But H alpha can more easily escape the galaxies once it’s produced. For one thing, it’s red light, and that can penetrate the gas and dust better than the ultraviolet ***** alpha light can. There are other more complicated reasons as well, but the point is, the galaxies were simply hidden from us before, but not anymore. By extrapolating their results, it looks like they found 90% of the distant Universe!

 

[Xelebes]

*phones home*

 

[TxRad]

90% of the Galaxies emit red light?

Talk about a bunch of red light districts. Ponosters unit.

 

[TheeGoatPig]

Why is the word Ly-man (no hyphen) censored on Literotica?

 

[3113]

Why is the word Ly-man (no hyphen) censored on Literotica?

I was wondering that myself I think there's something wonky with software for this site because on the rare occasions that a certain word in a post gets censored it's usually completely innocent. Not even trademarked.

 

[bronzeage]

Why is the word Ly-man (no hyphen) censored on Literotica?

Probably a user name of someone who was banned from Lit chat.