Stars form when dense clumps of interstellar gas and dust collapse under their own gravitational force. When a star emerges at the center of such a cloud, the remaining material forms a swirling disk around it that fuels stellar evolution and often gives birth to planets.
The disks around newborn Sun-sized stars contain much more matter than the disks around smaller stars, making it more likely that gas giant planets will form around these larger stars, like Jupiter and Saturn do around the Sun.
“They are the most common stars in our galaxy,” study co-author Thomas Henning, an astronomer at the Max Planck Institute for Astronomy in Germany, said of very low-mass stars.
“These objects are current targets in the search for rocky planets because they are easier to find around such stars. In addition, the mass of their planet-forming disks is usually too small to form giant planets, but large enough to form rocky planets,” Henning said.
Scientists have already identified rocky planets orbiting very low-mass stars, some of which are in the “habitable zone” — the orbital distance from a star where a planet might have conditions favorable for life.