During the annual winter meeting of the American Astronomical Society, NASA officials announced that Kepler space telescope discovered eight more exoplanets. With this event, NASA reached a historic milestone of the 1,000th newly verified exoplanet during its Kepler mission.
Kepler has been hunting extrasolar planets, or exoplanets, since June 2014. But on January 6, NASA marked Kepler’s current exoplanet tally to 1,004. NASA’s Kepler telescope has also identified 3,200 space objects that are waiting for verification. Space experts say that nearly 90 percent of those objects should turned out to be verified exoplanets.
NASA also hopes that a number of those would be Earth-like planets with hospitable space conditions to host life. Two out of the eight newly found exoplanets announced Tuesday are Earth-like planets, NASA officials say.
Kepler was designed to find these Earth analogues, and we always knew that the most interesting results would come at the end. So we’re just kind of ramping up toward those most interesting results. There’s still a lot of good science to come out of Kepler,”
said Natalie Batalha, Kepler mission team member.
Exoplanet research is a recently new field. In 1992, the first alien world that didn’t belong to our solar system was confirmed, while in 1995, scientists found the first exoplanets revolving a sun-like star. The Kepler mission was first launched in March 2009 with the goal of measuring exoplanet frequency within the Milky Way galaxy.
Kepler telescope usually identifies a new exoplanet when the planet crosses the face of the host star around which it revolves. This method is called “transit method.” However, there are other methods employed such as transit timing variation, relativistic beaming and gravitational microlensing. The latter is used to detect white dwarfs, black holes and neutron stars. Kepler also measures the amount of reflected light from some exoplanets to find new objects that would go undetected with the transit method.
When using the transit method, Kepler needs to record several transits to make sure it is observing an exoplanet. So, for some planets that take longer time to revolve around their host star it may take years to get identified as exoplanets, while giant, close orbiting planets such as “hot Jupiters” with no potential for hosting life can be easily confirmed as planets.
Before, we were just kind of plucking the low-hanging fruit, and now we’re getting down into the weeds, and things are getting a little harder. But that’s a challenge we knew we would have,”
Mrs. Batalha also said.
Newly found planet candidates are then confirmed as exoplanets by further observations made with different space instruments or by statistically analyzing Kepler’s data.
Image Source: Universe Today