They sure are. Have a look at the Space Interferometry Mission home page. This is a proposed optical/infrared interferometer operating in space with the resolution and sensitivity needed to detect earth-sized planets around the nearer stars. A simple study of the spectra of these planets would determine whether any free oxygen exists signaling the presence of living systems; either bacteria or plants. The cost of such a project is less that $500 million and the facility would be available during the first decades of the next century.
According to the JPl information page on SIM:
How big is the universe? How old is it? Are there other planets like Earth out there among the stars? We have asked these questions around campfires and in the halls of universities for centuries. Today, we know that the answers lie hidden in the positions and distances of the stars and galaxies. And each time scientists have measured these positions and distances with greater accuracy, they have gained a wealth of new understanding.
The Space Interferometry Mission (SIM), scheduled for launch in 2006, will determine the positions and distances of stars several hundred times more accurately than any previous program. This accuracy will allow SIM to determine the distances to stars throughout the Galaxy and to probe nearby stars for Earth-sized planets. SIM will also pioneer a technique to block out (null) the light of bright stars to take images of the interesting areas close to the star. SIM will open a window to a new world of discoveries.
This breakthrough in capabilities is possible because SIM will be the first space mission to use optical interferometry. Pioneered by Albert Michelson, who became the first American to win the Nobel Prize in physics in 1907, optical interferometry can fulfill its full potential only outside the distorting effects of Earth's atmosphere. There, it can combine light from two or more telescopes as if they were pieces of a single, gigantic telescope mirror. Developed for use in space with SIM, this technique will eventually lead to the development of telescopes powerful enough to take images of Earth-like planets orbiting distant stars and to determine whether these planets sustain life as we know it.
SIM is being developed by the Jet Propulsion Laboratory under contract with NASA and in close collaboration with two industry partners, Lockheed Martin Missiles and Space in Sunnyvale, California, and TRW Inc., Space and Electronics Group in Redondo Beach, California.
Copyright 1997 Dr. Sten Odenwald
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