Scientists have discovered nearly 80 exoplanet candidates in the latest data returned by K2, NASA’s extended planet-hunting mission.
During K2’s 16th and 17th observation periods, known as C16 and C17, K2 looked at approximately 50,000 stars. Each observation, in which the telescope studies one patch of the sky, lasts for 80 days.
One particularly noteworthy planet candidate orbits the brightest star ever studied by K2. Known as HD 73344, the star, which is located approximately 114 light years from Earth, is orbited by a “hot Neptune” type planet that circles it every 15 days.
Estimated to be around 2.5 times the size of Earth and about 10 Earth masses, the planet has an estimated temperature of 2,000 degrees Fahrenheit (1,200-1,300 degrees Celsius), which is close to the temperature of lava in an erupting volcano.
“We think it would probably be more like a smaller, hotter version of Uranus or Neptune,” said study co-leader Ian Crossfield of MIT.
The science team that analyzed the latest K2 data did so in record time, using technological tools developed at MIT to help them sift through the graphs, known as light curves, within just two weeks of their return by K2.
This type of analysis ordinarily takes several months to a year.
Such quick detection of planet candidates allows astronomers to follow up on the findings by observing the planet candidates with ground-based telescopes.
Quicker follow up observations make it easier for scientists to detect additional transits, from which they confirm candidate planets actually exist.
“We found one of the most exciting planets that K2 has found in its entire mission, and we did it more rapidly than any effort has done before. This is showing the path forward for how the TESS mission is going to do the same thing in spades, all over the entire sky, for the next several years,” Crossfield emphasized.
TESS, which stands for Transiting Exoplanet Survey Satellite, is NASA’s new planet-hunting space observatory, which was launched on April 18 of this year. Like Kepler, it will use the transit method to search for planets but will observe an area of the sky 400 times larger than that studied by Kepler.
In a paper on their findings published in The Astronomical Journal, the researchers note, “Our experience with four years of K2 data leads us to believe that most of these are indeed real planets, ready to be confirmed or statistically validated.”
In addition to finding the planet candidates, the scientists who analyzed the data also discovered a supernova in another galaxy and possible signatures of pulsating stars.