"Many stars are apparently surrounded by systems with several planets", stated Stefan Dreizler, a professor at the University of Göttingen and a co-author of the study.
The star the two planets are orbiting was discovered in 2003 and was named Teegarden's star.
If the orbit and rotation speeds recorded by astronomers is accurate, and there are no unexpected factors in the solar system to disrupt other calculations, Teegarden's two planets, which are nearly exactly the same mass as the Earth, could host rocky environments and flowing water, according to CNN. Teegarden b and Teegarden c were added to the Habitable Exoplanets Catalog. After three years, the team detected the wobbles produced by Teegarden b and Teegarden c. Researchers observed it as part of the larger CARMENES survey for exoplanets, and found evidence for a pair of planets orbiting the star.
The scientists noted that these objects are very similar to the rocky inner planets of the Solar system.
The results were obtained as part of the CARMENES search for exoplanets; CARMENES stands for "Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs". The habitable zone around any star is the distance at which a planet can orbit where it is neither too hot nor too cold for liquid water to persist on its surface.
The innermost world, Teegarden b, has more potential, with a 60 percent chance of having a "temperate surface environment" within the temperature range of about 32-122 degrees Fahrenheit (0-50 degrees Celsius), according to the Planetary Habitability Laboratory.
It is only about 2,700 °C warm and about ten times lighter than the Sun.
"The structure of the solar system is quite different, but the important point is the mass of the planet is very similar to Earth", Delaney said. The project's aim is to seek out worlds orbiting within the habitable zones of small red dwarf stars.
Each has an estimated minimum mass of 1.1 times Earth, and orbit their star every 4.91 and 11.4 days, respectively.
The team of researchers, including Ribas, is now using the CARMENES instrument to search for planets orbiting 342 stars, The telescope is located at Spain's Calar Alto Observatory.