NASA’s planet-hunting Kepler mission recently released what it calls the most comprehensive and detailed catalog of candidate exoplanets.
Exoplanets or extrasolar planets are planetary bodies that exist outside of our solar system.
The new and final Kepler catalog from data gathered from the spacecraft’s initial patch of sky view within the Cygnus constellation includes 219 new planet candidates.
Ten of the new candidates are said to be near-Earth sized and are orbiting within its star’s habitable or Goldilocks zone, which is an orbital region where it’s not too hot nor too cold and where liquid water could be found on the surface of a planet.
With the 219 planets that have been added to the new catalog, Kepler’s count of candidate exoplanets it has found is now at 4,034.
Of them, NASA says 2,335 have been verified or confirmed as actual exoplanets.
Among the planet candidates, about 50 are said to be near-Earth sized and also reside in its star’s habitable zone. More than 30 of the 50 have been verified, said the space agency.
The new catalog of extrasolar planets was built with data collected during the first four years of the Kepler mission, which began on May 12, 2009.
NASA says the data used to put the new catalog together is also available to the public in the space agency’s Exoplanet Archive.
Serious technical problems in 2012 and 2013 threatened to end Kepler’s mission.
So instead of giving up on Kepler, NASA proposed a modification and extension of its mission called K2 that has been operating since.
So far, the K2 mission has spotted 520 exoplanet candidates with 148 of them confirmed discoveries.
The technique used by the Kepler spacecraft to look for planets beyond our solar system is known as the transit method.
Above Video: Kepler measures the brightness of stars. The data will look like an EKG showing the heart beat. Whenever a planet passes in front of its parent star as viewed from the spacecraft, a tiny pulse or beat is produced. (NASA Ames Research Center)
With this system, astronomers point their telescopes at a star and any slight and temporary dip in its brightness could indicate an object such as a planet is passing in front of it.
Along with extra-solar planet candidates found by the Kepler and K2 missions, the Extrasolar Planets Encyclopedia also lists additionally confirmed exoplanets that were discovered with other means and methods, bringing the total number of confirmed exoplanets to about 3,500.
With the release of the new exoplanet catalog, there is a new international study, led by researchers at the California Institute of Technology (Caltech) who have used methods similar to how biologists identify new species of animals to classify these confirmed planets.
According to the study, most planets found so far in the Milky Way Galaxy fall into two categories and that nearly every star has at least one planet larger than Earth but smaller than Neptune.
They are either rocky, like Earth, with sizes nearly 2 times that of our planet or are gas-covered worlds, like the four outer planets Jupiter, Saturn, Uranus, and Neptune, that are between 2 to 3.5 times the size of Earth but are smaller than Neptune.
Ironically in our own solar system, the scientists say there aren’t any planets that are sized between Earth and Neptune.
The Caltech team used data gathered by the W. M. Keck Observatory, atop Mauna Loa in Hawaii and NASA’s Kepler mission to make their findings.