In Brief
NASA's Kepler spacecraft has combined data from Earth-based telescopes and found 197 planet candidates and 104 exoplanets (four of which could host Earth-like alien life).

More Telescopes, More Discoveries

Using data from NASA’s Kepler spacecraft on its K2 mission, and combining them with follow-up observations from earth-based telescopes, an international team of astronomers have tallied a total of 197 initial planet candidates. Notably, they also discovered 104 confirmed exoplanets (also known as ‘alien worlds’).
Moreover, four of them feature rocky terrains, meaning that they could potentially host Earth-like alien life; however, they could also be dead worlds like Venus or Mars. Still, the more rocky worlds, the more chances of finding Earth 2.0 and life like ours.
The find also features giant planets that are between 20 to 50% bigger in diameter than Earth and are all orbiting dwarf star K2-72, which is about half the size of the Sun and is found 181 light-years away.
The planets were situated tightly, orbiting their host star at distances where they can make a full orbit between five and a half to 24 days. Despite this proximity, scientists are not ruling out the possibility of life within the star system.

Artist concept of Kepler on its treasure find. NASA/JPL.
Artist concept of Kepler on its treasure find. NASA/JPL.
“This bountiful list of validated exoplanets from the K2 mission highlights the fact that the targeted examination of bright stars and nearby stars along the ecliptic is providing many interesting new planets,” said Steve Howell, project scientist for the K2 mission at NASA’s Ames Research Center. “These targets allow the astronomical community ease of follow-up and characterization, providing a few gems for first study by the James Webb Space Telescope, which could perhaps tell us about the planets’ atmospheres.”
It took a battalion of telescopes from both the northern and southern hemispheres to come to this copious discovery: the North Gemini telescope and the W. M. Keck Observatory in Hawaii, the Automated Planet Finder of the University of California Observatories, and the Large Binocular Telescope operated by the University of Arizona.

The Kepler’s Second Life

The Kepler project being extended into the K2 mission would not have happened if it weren’t for a resourceful fix engineers devised in 2013 to keep it running despite losing its second of four gyroscope-like reaction wheels.
“A severe malfunction had robbed the planet-hunting Kepler of its ability to stay pointed at a target without drifting off course,” NASA recalls.
“Many of us believed that the spacecraft would be saved, but this was perhaps more blind faith than insight,” said Tom Barclay, senior research scientist and director of the Kepler and K2 guest observer office at NASA’s Ames Research Center in California’s Silicon Valley. “The Ball team devised an ingenious solution allowing the Kepler space telescope to shine again.”

The fix.
The fix.
So far, the extension has proven over and over that it was well worth the second try. It now covers more of the sky and can observe larger fractions of cooler, smaller, red-dwarf type stars, which are very common in the Milky Way.