A mission-saving spur-of-moment fix to stabilize NASA's Kepler telescope may have just helped Earth find its closest planetary relative outside our solar system, possibly harboring life.
In its biggest haul yet, the telescope found 104 planets outside the solar system of which at least four are known to be rocky. These four extraterrestrial bodies orbit the dwarf star K2-72, located about 181 light years from Earth. Given that the star is an M dwarf, relatively cooler and half the size of Sun, the rocky planets around it are probably orbiting the star in the system's habitable zone, providing a chance for life to take shape.
Kepler was originally launched to observe a patch of sky in the northern hemisphere. It found planets by noticing a subtle dip in the light of host stars when planets passed the star. During an extended run in 2013, one of the telescope's reaction wheels that balanced and pointed it towards a predesignated portion of the sky, gave away causing the telescope to sway and nearly ending the mission. However, its handlers on Earth devised an ingenious plan to use sunlight's physical force on Kepler's solar panels to compensate for the balance loss. This gave birth to Kepler's K2 mission and resulted in a haul of 197 planets of 104, including the ones around K2-72 were confirmed, The Washington Post reported.
The K2 mission now scans a portion of the sky that contains more stars than earlier as it looks for red stars with Earth-like planets orbiting in its expanded field of vision.
"An analogy would be to say that Kepler performed a demographic study, while the K2 mission focuses on the bright and nearby stars with different types of planets," said Ian Crossfield, lead author of the paper that discussed Kepler's recent haul. "The K2 mission allows us to increase the number of small, red stars by a factor of 20, significantly increasing the number of astronomical 'movie stars' that make the best systems for further study."
With the scientific community directing what the Kepler sees and with frequent repositioning to keep the telescope balanced with Sun's energy, Kepler is likely to win the race for life search outside Earth.
