Tau

Binary system

Its story

Tau Ophiuchi is a multiple system 167 light-years away: two yellow-white stars orbiting each other every 257 years in a highly elongated ellipse, with a faint third component sitting a hundred arcseconds out. The primary also hides a small dwarf companion that circles it every 186 days. The visual orbit has been patiently tracked since 1835 with over six hundred observations, a near two-century-long conversation between astronomers.

Constellation: Ophiuchus
Apparent magnitude: 4.77
Distance: 167.5 light years
Coordinates (J2000): RA 270.771° · Dec -8.180°
Catalogue: HIP 88404 · HD 164764

Take your star to the gift that suits you best.

Choose a tier

Symbolic commemorative gift — no ownership, no IAU recognition.