NASA's planetary hunting satellite, the Transiting Exoplanets Survey (TESS), has discovered a new discovery in the depths of the universe. Last month, TESS discovered its first exoplanet. And now she reached another milestone where she found her first Earth-sized planet and a larger sibling planet.
Planet Earth, 21749c in size, and its star sibling track slightly smaller than our Sun, which is 53 light-years from Earth. HD 21749c is a rocky planet that orbits its star every eight days, which means it moves near its star and has high surface temperatures of up to 800 degrees Fahrenheit.
"For stars that are very close and very clear, we expected to find dozens of planets in the planet," says Diana Dragomir, TESS lead author and member, Postdoctoral, Astrophysics and Space Research Institute, Massachusetts Institute of Technology. , he said in a statement. "And here we are – that would be our first and it is a milestone for TESS. It sets the path to finding smaller planets around smaller stars, and these planets can be potentially habitable. "
The larger planet is classified as the warm world of sub-Neptune, which has a mass about 23 times the Earth and a radius of about 2.7 times the Earth. Named HD 21749b, it is unusual in that it takes 36 days to complete orbits, which is considerably more than the orbital time of 10 days that was expected for most planets that the mission would find.
To find the planets, TESS was looking for a small drop in the amount of light emitted by the host star HD 21749, which occurred at regular intervals. This indicated that light from the star was blocked by the transition of planets between it and Earth.
"It's so exciting that the TESS, which was launched just a year ago, is already a change in the game on the planet," said Johanna Teske of Carnegie Institution for Science, second author on paper. "The spacecraft explores the sky and works with the TESS community to track potentially interesting targets for further observation using ground-based telescopes and instruments."
The results are published in the Astrophysical Journal Letters.