The night sky lit up as NASA‘s Kepler telescope rocketed into the atmosphere above Cape Canaveral, which is located off the Atlantic coast of Florida.1 Thousands of people watched the launch from Earth. But was anyone watching from space? The Kepler space telescope will help answer that question. When the telescope blasted into space, it became part of the worlds’2 first space mission dedicated in searching3 for Earthlike planets.
The telescope is named for Johannes Kepler, the 16th century German astronomer who discovered that planets orbit in an oval-shaped path rather than in4 circles, as was believed there.5 Kepler was first to suggest that the sun rotates on its axis. He was also the first to correctly explain how vision and telescopes work, and he helped legitimize6 Galileo’s theories.
Kepler carries the largest camera ever launched into orbit. The camera will look for planets by studying regular dips in the brightness of stars. The tiny dips in brightness are invisible to the naked eye created by planets passing in front of their stars as they orbit.7 If Kepler were to look down at a small town on Earth at night from space, though,8 it would be able to detect the dimming of a porch light as someone passed in front. [9]
Kepler is designed to find planets that are like ours. These planets would have rocky cores and would be about the size of Earth. They would also be the right temperature to have liquid water – the main ingredient10 for life resembling that found on earth. “We’re looking for planets in the Goldilocks zone – not too hot, not too cold,”11 explains Lia LaPiana, who works on NASA‘s Kepler team. If a planet is too close to a star, the temperature is too high. If it’s too far away, it is too low.
The mission having been described12 as a planetary census. However, Kepler will only examine a small wedge of space. The telescope itself cannot detect life forms. It can only identify planets where the presence of life is possible as we know it.13 The NASA team will study the data about those planets and look for more clues. Future spacecraft may be sent to follow up.
Even if Kepler fails to make any promising sightings, the mission will have been a success. If no14 Earthlike planets found in the habitable zone would be a pretty strong indication that the way our solar system is formed is very rare. [15]