In an announcement Wednesday, NASA reported discovering 715 new exoplanets spread across 305 planetary systems of the galaxy. The planet hunters at NASA used the Kepler space telescope in these significant findings. According to NASA planetary scientist Jack Lissauer, “We’ve almost doubled today the number of planets known to humanity.” The findings of the NASA planetary team will be published in the March issue of the Astrophysical Journal.
Prior to the discovery of this new batch of exoplanets (or planets) lying outside the solar system, around 1,000 planets have so far been identified in the galaxy. Using a new technique called “verification by multiplicity,” the scientists hope to discover more of these planets outside of the solar system more frequently. The technique relies on the use of probability instead of searching the universe blindly, with no specific focus. This will require using the Kepler space telescope on the part of the universe where more than one planet is likely to orbit its star.
NASA also reported that 95 percent of the planets discovered by Kepler are smaller in size compared to Neptune. Neptune is four times larger than the size of Earth. Four of these planets are in the so-called “habitable zone” of their stars, which is a distance that allows water to be in a liquid state.
Included in the four planets within the habitable zone is a planet which orbits a star half the size of the sun. It was estimated that it orbits in a 30-day cycle, and the said planet is double the size of Earth, while the other three planets in the zone are estimated to be of the same size as Earth.
According to the scientists involved in the project, the current technology involves first discovering a planet close to its parent stars. After more data come in and are verified, information about the planets’ climates could then be extracted.
Kepler employs a technique where the dimming of the stars’ focus is taken as a sign that a planet passed by or did a “transit.” The alignment, however, of the space telescope, star and the planet can only happen by pure chance. This also means planets orbiting their parent star at a great distance have a lower probability of being detected by Kepler.
These new planetary findings are a result of the first two years of the space telescope’s data collection and data verification. The $600 million Kepler space telescope was meant to discover Earth-like exoplanets within the habitable zone, which was launched by NASA on March 7, 2009. It was named after the Renaissance astronomer Johannes Kepler.
Previously, the scientists at NASA had announced thousands of possible exoplanets. But this new batch of planets has been verified with 99 percent confidence. The scientists calculated and validated the data by using the “false positive” methodology.
Another planetary scientist at NASA’s Ames Research Center in California said, “We’ve been able to open the bottleneck to access the mother lode and deliver to you more than 20 times as many planets as has ever been found and announced at once.” Meanwhile, Douglas Hudgins of the NASA’s astrophysics unit said the Kepler space telescope has been a game changer in terms of understanding the diversity in the universe.
The announcement Wednesday by NASA planet hunters upon discovering 715 new exoplanets spread across 305 planetary systems of the galaxy is indeed significant. According to SETI Institute research scientist Jason Rowe, the more we explore the universe, the more we are reminded of home.
By Roberto I. Belda