Monday, October 10, 2011

Money's Worth

So the new Friar vacation destination of choice is the Andes mountains in Chile.

Specifically, the Chajnator Plateau in the Atacama desert, home of the Atacama Large Millimeter/submillimeter Array telescope, the world's most expensive telescope which has been designed to see things using radio waves. The telescope, called ALMA, uses those radio waves to see what astronomers call "cold matter" that regular visible-light or infrared-light telescopes can't see.

Most of what we see in the sky is hot so it radiates energy in many forms, among them visible light and heat. If something doesn't radiate energy of some kind, we can't really see it unless it's between us and a light source. But ALMA's use of radio waves means it can detect matter that's not radiating as much energy as things like stars do. The picture at the story is one of two galaxies smacking into each other ("smacking" being a relative term as they are taking many millions of years to do it) and shows detail and form that previous telescopes would not have been able to resolve. And it's what astronomers can see with just a third of the many antenna arrays ALMA will eventually use.

The "millimeter/sub-millimeter" part of the telescope name refers to the wavelengths of light that ALMA can "see." Things like light, sound and radiation come in waves rather than particles, and the distance between the crest of each wave is that energy's "wavelength." Visible light has a high energy level and so its wavelength is shorter. If you tied one end of a rope to a post and held the other end as you moved your arm up and down, you would make waves in the rope. Move your arm swiftly and there would be more waves in the length of rope and their wavelength would be shorter. Move your arm slowly and there are fewer waves, so their wavelength is longer. By receiving signals in the millimeter/sub-millimeter range, ALMA can see things that give off much less energy or are "cold" in astronomer's terms.

None of which figures out how to get me to Chile anytime soon, so I'll leave you while I try to come up with a plan.

4 comments:

latoberg said...

Save your money until it comes online completely.

latoberg said...

By the way, have you used SLOOH yet? They have a Jupiter event coming up tomorrow. I don't know how much they are doing with it, though.

Friar said...

Not familiar with SLOOH?

latoberg said...

It seems to be an online observation site that allows viewers to tap into telescopes from around the world. I'm too cheap to buy into it (paid service), but I believe they allow free viewing for big events.