BD+00 316

BD+00 316 is an ordinary star with a close-orbiting planetary companion in the equatorial constellation of Cetus. It is also known as WASP-71 since 2019; BD+00 316 is the stellar identifier from the Bonner Durchmusterung catalogue. With an apparent visual magnitude of 10.56, it is too faint to be visible to the naked eye. This star is located at a distance of 1,160 light-years based on parallax measurements, and is drifting further away with a heliocentric radial velocity of 7.7 km/s.

This is classified as an F-type star with a stellar classification of F8. It is more than double the diameter of the Sun with 1.5 times the Sun's mass. The star is younger than the Sun at about 3.6 billion years, yet is already evolving away from the main sequence. BD+00 316 is enriched in heavy elements, having 140% of the solar abundance of iron. Imaging surveys in 2015 and 2020 failed to find any stellar companions for BD+00 316.

The star was named Mpingo by Tanzanian amateur astronomers in 2020 as part of the NameExoWorlds contest, after the mpingo tree (Dalbergia melanoxylon) whose wood is a type of ebony used in musical instruments.

Planetary system
In 2012 a transiting superjovian planet, designated component b, was detected on a tight, circular orbit. The planetary orbit is well aligned with the equatorial plane of the star, the misalignment angle being equal to −1.9$$°. Its equilibrium temperature is 2,016.1$$ K.

The planet was named Tanzanite by Tanzanian amateur astronomers in 2020 as part of the NameExoWorlds contest, after the mineral also known as tanzanite.