HD 92945 is a K-type main sequence star located 70 light years away in the northern constellation of Hydra. Its apparent visual magnitude varies by 0.02 magnitudes and is approximately 7.72 at maximum brightness.
Debris disk
In 2007, a debris disk with estimated dust mass has been observed around the star by coronagraphic imaging, using the ACS and NICMOS instruments on the Hubble Space Telescope. It appears to extend 45 to 175 astronomical units from HD 92945.
The disk has a gap wide at a radius of , which may be being carved by a planet. No planet with mass exceeding 1-2 was observed in the gap, but a lower-mass planet or a chain of two planets are still possible.
Evidence for a planet via astrometric observations was presented in 2024. It could be explain the presence of the gap through long-term resonances with the disk, as its orbital separation is much less than the gap's radius and thus the planet would not be carving the disk directly. Alternatively, both the inner planet and an additional planet within the gap could be shepherding the disk through long-term gravitational interactions.
References HD 92945, database entry, The Geneva-Copenhagen Survey of Solar neighbourhood, J. Holmberg et al., 2007, CDS ID V/117A. Accessed on line February 2, 2011.
V419 Hya, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars , Sternberg Astronomical Institute, Moscow, Russia. Accessed on line February 2, 2011.