In the observatory, the astronomer is studying at his desk.

In general, this allows astronomers to study objects as they were many millions or even billions of years ago.

Soon, astronomers might be studying systems of planets orbiting other stars.

Our best scientists have studied you like astronomers studying a distant star.

Until its discovery last year, this comet had never been seen before, and astronomers are studying it with keen interest.

Since X-rays do not penetrate very deeply into the atmosphere, astronomers must study them from space.

For thousands of years, astronomers studying the solar system have noticed that these planets march across the sky in a predictable way.

The astronomers were studying a nearby nova, so they caught the intruder a little sooner.

Radio telescopes allow astronomers to study deep space by analyzing radio waves.

The astronomers also studied planet 581d again, and made more accurate measurements for that planet.