The host star, TOI-6894, is a red dwarf with only 20% the mass of the Sun, typical of the most common stars in our galaxy. Until now, such low-mass stars were not thought capable of forming or retaining giant planets. But as published in Nature Astronomy, the unmistakable signature of a giant planet — TOI-6894b — has been detected in orbit around this tiny star.

The University of Warwick and UCL astronomers, as part of a global collaboration including partners in Chile, USA, and Europe, have discovered the smallest known star to host a transiting giant planet, which should not exist under leading planet formation theories. 

Most stars in the Universe exist in binary or multiple star systems, where the presence of close-in companion stars in such systems can adversely influence the formation and orbital stability of planets around one of the stars. An international team of astrophysicists led by Professor Man Hoi LEE from the Department of Earth Sciences and the Department of Physics at The University of Hong Kong (HKU) and Mr Ho Wan CHENG, an MPhil student in his team, has confirmed the existence of a planet in an unprecedented retrograde orbit (moving in the opposite direction to the binary’s orbit) in the nu Octantis (nu Octantis) binary star system and revealed the role of binary star evolution in the origin of this planet. The findings have been published in the journal Nature.

Scientists from the University of Chicago have made a new calculation of the speed at which the universe is expanding, using the data taken by the powerful new James Webb Space Telescope on multiple galaxies.