The discovery of a new Earth-sized planet orbiting a star that will live 100 billion years

Using the International Robotic Telescopes, researchers have discovered an Earth-sized planet, SPECULOOS-3 b, orbiting an ultracool red dwarf within the galaxy. milky way. The planet, which is tidally locked and likely lacks an atmosphere due to intense radiation, offers new insights into long-lived red dwarfs, which are expected to be among the last burning stars in the universe.

Our galaxy is a treasure trove of red stars. In fact, more than 70% of the stars in the Milky Way are M dwarfs, also known as red dwarfs. These stars are cool and dim compared to our Sun, but they often blast the exoplanets they orbit with high-energy radiation, especially early in their lives. And that “life” lasts forever long time. Stars like our Sun burn for about 10 billion years before turning into hungry red giants that devour any planets that are too close. M dwarfs continue to burn for 100 billion years or more, perhaps providing a foothold for life, and a longer window for life to evolve.

An international team using robotic telescopes around the world recently discovered an Earth-sized planet orbiting an ultracool red dwarf, the lightest and longest-lived star among stars. When the universe gets cold and dark, these will be the last stars to burn out.

Discovery

the Exoplanet SPECULOOS-3 b is located about 55 light-years from Earth (really close when you consider the cosmic scale!) and about the same size. A year there, one revolution around the star, takes about 17 hours. However, the days and nights may never end: the planet is thought to be tidally locked, so the same side, known as the day side, always faces the star, like the Moon to Earth. The night side will be sealed in never-ending darkness.

An artist’s concept of the exoplanet SPECULOOS-3 b orbiting its red dwarf star. The planet is as large as Earth, while its star is slightly larger than Jupiter – but much more massive. Credit: Leonel Garcia

Exploring ultra-cold dwarfs

In our corner of the galaxy, ultracool dwarf stars are everywhere. They are so faint that their planetary populations are largely unexplored. The SPECULOOS (Search for Planets Obscuring Ultracool Stars) project, led by Michael Gillon at the University of Liège in Belgium, is designed to change that. Ultracool dwarf stars dot the sky, so you’ll have to observe them one by one, for weeks, to have a good chance of spotting transiting planets. To achieve this, you need a dedicated network of professional telescopes. This is the SPECULOOS concept.

“We specifically designed SPECULOOS to explore nearby ultracool dwarf stars in search of rocky planets,” Gillon said. ”With the SPECULOOS prototype and crucial assistance from NASA Spitzer Space Telescope, we discovered the famous TRAPPIST-1 system. That was an excellent start!

Gillon is lead author of the paper announcing the planet’s discovery, which was published May 15, 2024, in the journal Nature astronomy. The project is a truly international endeavour, in partnership with the universities of Cambridge, Birmingham, Bern, MIT and ETH Zurich.

The SPECULOOS-3 star is thousands of degrees cooler than our Sun, with an average temperature of about 4,760 F (2,627 C), but it hits its planet with radiation, meaning it likely has no atmosphere.

Seeing a star, let alone a planet, is an accomplishment in itself. “Although this particular red dwarf is more than a thousand times fainter than the Sun, its planet orbits at a much closer distance than Earth,” said Katherine Clark, co-author and postdoctoral researcher at NASA’s Jet Propulsion Laboratory. To heat the planet’s surface. In Southern California.

Fun facts

• While the planet is as large as Earth, its star is slightly larger Jupiter – But much more massive.
• The planet receives approximately 16 times more energy per second than the Earth receives from the Sun.
• Did you catch the cookie connection? SPECULOOS Planet Discovery shares its name with spiced shortbread. They both hail from Belgium. sweet!

Next steps

SPECULOOS-3 b is an excellent candidate for follow-up observations with the James Webb Space Telescope. Not only will we learn about the possibility of an atmosphere and surface minerals, it may also help us understand the stellar neighborhood and our place in it.

“We are making great strides in our study of planets orbiting other stars. We have now reached the point where we can detect and study Earth-sized exoplanets in detail. “We are making great strides in our study of planets orbiting other stars,” said Steve P. Howell, one of the planet discoverers at NASA’s Ames Research Center in Silicon Valley. Next will be to determine if any of them are habitable, or even inhabited.

For more on this discovery:

Reference: “Discovery of an Earth-sized exoplanet orbiting the ultracool dwarf star SPECULOOS-3” by Michael Gillon and Peter B. Pedersen, and Benjamin V. Rackham, Georgina Dranfield, Elsa Ducrot, Khaled Al-Barqawi, Artem Burdanov, Urs Schrofenegger, Yelin Gomez Maco-Chiu, Susan M. Lederer, Rui Alonso, Adam J. Burgasser, Steve B. Howell, Norio Narita, Julien de Wit, Brice Olivier Demaury, Didier Queloz, Amaury HMG Triaud, Laetitia Delrez, Emmanuelle Jehin, Matthew J. Hutton, Leonel J. Garcia, Claudia Jano Muñoz, Catriona A. Murray, Francisco J. Pozuelos, Daniel Sebastian, Mathilde Timmermans, Samantha J. Thompson, Sebastian Zuniga Fernandez, Jesús Acetono, Cristian Ajanzi, Pedro J. Amado, Thomas Bycroft, Zuhair Bin Khaldun, David Berardo, Emeline Polmont, Katherine A. Clark, Yasmin T. Davis, Fatima Davoudi, Zoe L. de Bourse, Jerome B. de Leon, Masahiro Ikoma, Kai Ikuta, Keisuke Isogai, Izuru Fukuda, and Akihiko. Fukui, Roman Gerasimov, Murat Gashui, Maximilian N. Günther, Samantha Hasler, Yuya Hayashi, Kevin Heng, Renyu Hu, Taiki Kagitani, Yugo Kawai, Kyo Kawauchi, Daniel Kitzmann, Daniel D. B. Cole, Monika Lindell, John H. Livingston, Shentong. Liu, Eric A. Mayer Valdés, Mayuko Mori, James J. McCormack, Felipe Morgas, Prajwal Niraula, Enrique Bali, Elsie Blaucho-Frayne, Rafael Rebollo, Lawrence Sabin, Yannick Schacki, Nicole Schanech, Frank Celces, Alfredo Sotta, Manu Stalbort. , Matthew R. Standing, Kevan J. Stasson, Motohide Tamura, Yuka Terada, Christopher A. Thiessen, Martin Torbet, Valerie van Grootel, Roberto Varas, Noriharu Watanabe, and Francis Zhong Lang, May 15, 2024, Nature astronomy.
doi: 10.1038/s41550-024-02271-2