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What is a space MASER for?
This is for Mark G, I know how a maser works but what does it do in space? is it used for measuring distances to planets,from an earthbound radar station, or on spacecraft for peering through clouds on Earth, Titan and Venus
Thank you mark, that was usefull, Alan
2 Answers
- Mark GLv 710 years agoFavorite Answer
I assume you know how a laser works.
In certain astrophysical environments some molecular species have enhanced number densities compared to normal. They are exposed to either a radiation field or a shock which inverts their excited population such that they no longer have a Boltzmann distribution. A passing photon of the right energy causes simulated emission of a coherent photon which in turn causes simulated emission of a coherent photon. Hence we get a beam of coherent radiation which has exponential growth as it passes through the cloud ad , which for reasons I will not go into, is very tightly beamed.
From the ground we see these as microwave spots. They can be very very bright, up to KJy.
Molecular species that are known to mase include CH3OH, H2O, SiO and OH. They end to be strongly associated with star formation, although not exclusively so. Because they are so bright, and that the galaxy is optically thin at these frequencies I use them to trace star formation and star formation processes.
Hope that helps.
