Narrator: This is Science Today. Since March, NASA's Mercury Messenger has been orbiting Mercury, becoming the first spacecraft to circle the planet. On board to get data of the planet's composition is the first mechanically cooled gamma ray spectrometer in deep space. Physicist Morgan Burks of the Lawrence Livermore National Laboratory was part of the team who built the instrument.
Burks: This system is cooled with a device — think of it as a very tiny refrigerator that can fit in the palm of your hand — and it's able to cool the detector to about minus 200 degrees Celsius. And at those temperatures is where we get the really high resolution. It's like the difference between a blurry fingerprint and a sharp fingerprint.
Narrator: Burks is part of the science team that's monitoring the instrument's performance and says so far it's been excellent.
Burks: Significantly, it survived two of the hot seasons of Mercury, where part of the spacecraft sees temperatures as high as 660 or something Fahrenheit and it survived that just fine.
Narrator: The Mercury Messenger spacecraft plans to circle the planet every 12 hours for one year. For Science Today, I'm Larissa Branin.