Launching people into space may make headlines but it does little useful science. So when George Bush redirected Americas space agency, NASA, away from scientific research and towards a manned return to the moon in 2004, many scientists were disappointed. Now the agency has finally offered some small morsels of comfort in the form of four projects that could accompany efforts for a lunar return.
The most exciting of these is the plan for a radio telescope that could be placed on the far side of the moon. Such a device would look back at the early universe to the time when large-scale structures such as galaxies and stars formed. A lunar-based radio telescope would be able to detect long wavelengths that cannot be sensed on Earth because they are absorbed by the outermost layers of the planets atmosphere. Moreover by pointing the telescope away from the din of shorter-wavelength radio waves that are used for communication on Earth, astrophysicists would be able to see the early universe in unprecedented detail.
Finding alien life might also be possible with such a telescope. It would be able to map the magnetic fields of stars and exoplanets . It is the magnetic field of the Earth that protects its inhabitants from being bombarded by high-energy particles from space that would otherwise leave the planet sterile. Detecting a magnetic field surrounding an Earth-like exoplanet would prove a promising sign for finding extraterrestrial life.
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