Eta Telescopii
Eta Telescopii is a young, white-hued star in the southern constellation Telescopium. It is just barely visible to the naked eye with an apparent magnitude around 5. It lies about 158 light-years from Earth and is part of the Beta Pictoris Moving Group, a handful of young stars traveling together through space.
Eta Telescopii A, the bright primary star, is an A-type main-sequence star about 2.1 times as massive as the Sun and 1.6 times its radius. It shines roughly 24 times brighter than the Sun at a surface temperature of about 12,000 K. The star is very young, with an age around 12 million years, and it spins rapidly.
The system includes a brown dwarf, Eta Telescopii B, orbiting far from the primary. B has about 35 Jupiter masses and completes an orbit roughly every 1,100 years. Its orbit is quite elongated, with a distance from the primary ranging from about 70 to 210 AU, and it is tilted relative to the star's equator.
Eta Telescopii A also has dust disks. There is a belt of dust at about 4 AU and a more distant disk at roughly 24 AU from the star, indicated by infrared excess. Observations with the James Webb Space Telescope suggest the disks are mostly symmetrical but may be slightly misaligned with the brown dwarf’s orbit, hinting there could be another, as-yet-undetected planet between about 3 and 19 AU.
The system is part of a triple arrangement: the wide companion HD 181327 lies about seven arcminutes away and has its own debris disk, with a sharp inner edge near 82 AU. This disk implies there could be a planet somewhere in the 55–82 AU range shaping it.
In short, Eta Telescopii is a young, bright star with a dusty environment and at least one brown-dwarf companion, plus a distant companion star with its own disk. The overall setup suggests the possible presence of additional planets shaping the surrounding material.
This page was last edited on 3 February 2026, at 02:22 (CET).