This Issue:

Table of Contents

Cover Story

Cover Story - Spanish Version

Mini-Lesson

Comprehension Quiz

Teacher's Guide and Worksheets

Looking for Life

Spanish Translation

Andrea Delbanco

NASA's Kepler telescope blasted into space on March 6. It is the world's first space mission dedicated to searching for Earthlike planets. The telescope is studying a section of the Milky Way galaxy for planets that are the right size and temperature to support life.

The night sky lit up as NASA's Kepler telescope rocketed into the atmosphere above Cape Canaveral, in Florida. Thousands of people watched the launch from Earth. But was anyone watching from space? Is there life on other planets? The Kepler space telescope will help to answer that important question.

Kepler will survey a faraway patch of the Milky Way galaxy (see below), looking for planets with the necessary conditions to support life. The planet discovery mission could last up to six years, and is expected to cost around $600 million.

A Powerful Eye In the Sky

Kepler carries the largest camera ever launched into space. The camera will look for planets by studying regular dips in the brightness of stars. These tiny dips in brightness are created by planets passing in front of their stars as they orbit. The dips are not visible to the naked eye.

"If Kepler were to look down at a small town on Earth at night from space," says NASA's James Fanson, "it would be able to detect the dimming of a porch light as someone passed in front."

The planet-hunting telescope will make its first measurements about one month after launch. Other telescopes on the ground and in space will help Kepler, including NASA's Hubble and Spitzer telescopes. A team of NASA scientists will study the data that Kepler sends back to Earth.

The Goldilocks Zone

Kepler is designed to find planets that are like ours. These planets would have rocky cores. They would be about the size of Earth, ranging from one-half to twice Earth's size. They would also be the right temperature to have liquid water, the main ingredient for life as we know it. "We're looking for planets in the Goldilocks zoneonot too hot, not too cold," explains Lia LaPiana, who works on NASA's Kepler team. "If a planet is too close to a star, it is too hot. If it's too far away, it is too cold," she told TFK. "We are looking for the just-right zone where liquid water can exist, which is called the habitable zone."

The mission has been described as a planetary census. But Kepler will only examine a small wedge of space. The telescope itself can not detect life-forms. It can only identify planets where the presence of life as we know it is possible. 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 we find no Earthlike planets in the habitable zone," says LaPiana, "that would be a pretty strong indication that the way our solar system is formed is very rare."

Who Was Kepler?

The space telescope is named for Johannes Kepler. The German astronomer was born in 1571. Kepler discovered that planets orbit in an oval-shaped path, not in circles, as was believed at the time. 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.

Next: Happy Holi!