Hunting for Planets
Finding planets around other stars is hard. Planets are tiny relative to most other objects in the universe. And they can be a billion times dimmer than the stars they orbit.
Because planets in other solar systems are nearly impossible to see directly, astronomers have had to come up with innovative ways to hunt these covert objects. Only in the past couple decades has our technology and techniques been up to the task of finding extrasolar planets.
The Hubble Space Telescope has a wide range of astronomical pursuits — from studying black holes in distant galaxies to observing members of our solar system. So it isn't able to dedicate a lot of time to the hunt for extrasolar planets.
But that doesn't mean Hubble hasn't tried — or succeeded.
In fact, Hubble has conducted some of the farthest searches of extrasolar planets ever attempted. It has proven that enigmatic objects discovered by other telescopes are planets. And it has made some exoplanet "firsts."
Telescopes on the ground and in space have uncovered hundreds of planets beyond our solar system. The Hubble Space Telescope is not the most prolific exoplanet hunter at astronomers' disposal, but it has made unique and significant contributions to the discovery and study of dozens of far-off worlds. Its sharp vision has detected the farthest planets found so far. It captured the first visible-light image of a planet around another star. It has proven that some mysterious objects are planets. And it has answered questions about planets that no other telescope currently can.
As astronomers advance their techniques to seek out new planets and new information about these planets, Hubble will continue to work alongside other telescopes to satisfy our curiosity about worlds beyond our solar system.