A team of scientists from MIT and the University of Aarhus (Denmark) have identified a total of 74 planets that orbit their stars making circular orbits, just like the Earth and the rest of the planets in our solar system. These stars are hundreds of light years from Earth . The finding has been published in The Astrophysical Journal.
The researchers used data collected by NASA’s Kepler telescope, focusing their attention on 28 stars whose mass and radius had already been measured. The actual transit data revealed multiplanetary systems as well as the duration and transit of the orbit of each of the discovered exoplanets.
According to the study, the 74 planets orbit a total of 28 stars and are very similar in size to Earth. “Twenty years ago, we only knew about our Solar System and everything was circular. Everyone expected circular orbits everywhere. So we started the search for giant exoplanets, and we were suddenly faced with a whole series of eccentricities, so there was an open question as to whether this would hold for the smaller planets as well. Now we find that on these small planets, circularity seems to be the norm, ”explains Vincent van Eylen, the study leader.
Are planets fit for life? Their size, composition and distance from their stars make them feasible if we take into account that they also maintain a circular orbit like us. The circumstance of a regular orbit would support the presence of a stable climate throughout the year, unlike planets with more peculiar orbits that go through very drastic changes in temperature depending on whether they are excessively far from their star or terribly close.
“If eccentric orbits were common, it would be of concern for habitable planets, because they would have a wide variety of climatic properties. But what we found is that we probably don’t have to worry too much because circular cases are quite common, ”explains Van Eylen.
