We speak to the deputy project scientist Steve Howell on NASA’s Kepler Science team about the powerful telescope.
What makes Kepler unique?
Kepler is the only current mission capable of finding Earth-size planets, especially those in the habitable zone of their stars. This means it can find true Earth-like planets that may be able to support life as we know it.
What technique does Kepler use to find planets?
Kepler uses a technique called transit detection. We observe 150,000 stars continuously and search the signals we receive. We look for very small drops in light, which indicate that a planet has transited, or crossed, in front of its host star as it orbits around the star.
Where is Kepler looking?
Kepler is looking near the plane of the Milky Way galaxy, a location In the sky that contains many stars. The exact central location is between the constellations of Cygnus and Lyra and we examine a field of view of over 100 square degrees on the sky.
What are the key technologies in the telescope?
The telescope has a very simple design – a Schmidt telescope, and only one Instrument: a large digital camera. The telescope has lightweight mirrors and the camera has specially built charge-coupled devices (CCDs), the digital detectors we all use in our phone cameras. Kepler’s are far [more advanced though], being larger and more sensitive.
What are some of the most fascinating planets Kepler has found so far?
Wow, this is a tough one. Kepler has found small planets, the size of Earth and even smaller. These planets are rocky – that is, they have a solid surface like the Earth. So far, we have only found these types of planets orbiting too close to their sun so their surface temperature Is far too hot for life as we know it. Kepler has found planets larger than Jupiter too; scientists didn’t know this [was possible]. Kepler has also discovered solar systems, stars with many planets orbiting them; the record so far is six planets. Kepler has found planets orbiting binary stars too, which remind us of Star Wars when Luke [is watching] the double sunset.
What kind of ET life can we expect to find?
So far, probably none. We have found small, rocky planets but these are too hot. We have found planets within the right temperature range, but they are too large to support life, either by having a crushing gravity at their surface or being gaseous with no solid surface. Some may have large moons which could harbour life though. We simply do not know at present, but stay tuned…
Well, at present we have discovered over 2,300 exoplanets, with over 400 near the size of the Earth. In the next year or two It is anticipated that we will find a number of Earth-analogues – that is, small planets with rocky surfaces, able to host liquid water on their surface, and orbiting their stars at the right distance to allow their surface temperature to be just right for our kind of life.