There have been a lot of discoveries made far and near in our universe by NASA’s Kepler space telescope. The discoveries included a lot of so-called ‘exoplanets,’ or planets that aren’t close enough to be considered in our own solar system because they orbit their own host star.
A recent study led by a researcher team from the Instituto de Astrofísica (Insistute of Astrophysics), suggests that over half of the discoveries made with the Kepler’s SOPHIE spectrograph that were thought to be distant exoplanets may actually not be. Instead, they could be some kind of eclipsing binary star system, or they could be dying brown dwarf stars that are so dim they actually come off as a type of exoplanet.
From the data collected, which involved 129 samples out of 8,826 discoveries, 52.3% of them were eclipsing binary star systems, in which the shadows from the eclipsing would appear to be some kind of planet orbiting a host star, and 2.3% of them were brown dwarfs, or dying stars too dim to be distinguished between a reflective planet or a dying star.
“Detecting and characterizing planets is usually a very subtle and difficult task,” said Vardan Adibekyan, one of the researchers involved in the study. “In this work, we showed that even big, easy to detect planets are also difficult to deal with. In particular, it was shown that less than half of the detected big transiting planet candidates are actually there. The rest are false positives, due to different kind of astrophysical sources of light or noise.”
Because things can appear not as they seem from a first glance, going back later and looking at it a second time with additional equipment is necessary to help scientists learn what they’re really looking at. This might include spectroscopic follow-up observations after the initial discovery.
The research also helped shed some light on gassy exoplanets, suggesting that the gasses surrounding the solid core may not really be as heavily expanded as originally thought.
Source: Instituto de Astrofísica