Star profile

Yed Prior

Delta Ophiuchi · Ophiuchus

Red giant

3D likeness based on its real data · class M · ~3,200 K

What is Yed Prior

Yed Prior, 'the hand that precedes', together with Yed Posterior outlines the left hand of Ophiuchus, the serpent-bearer who wrestles a snake across half the summer sky. It is a cool red giant, swollen and ruddy, lying about 171 light-years away: the coppery tone is visible to the naked eye against the bluish-white of its sky-mate. The light reaching the eye tonight first set out around 1855, in the years just before electric lighting began to dim the world's night skies.

Where it is and when to see it

Yed Prior lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is May: the Sun sits at the opposite point of the sky and the star culminates around midnight. How high it climbs above the horizon depends on the latitude you watch from.

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Astronomical data for Yed Prior

Constellation: Ophiuchus
Apparent magnitude: 2.73
Distance: 171.1 light years
Coordinates (J2000): RA 243.586° · Dec -3.694°
Catalogue: HIP 79593 · HD 146051

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Other stars in Ophiuchus

Ophiuchus has 88 stars in Stelvia's catalogue. Here are a few of them.

See all 88 stars in Ophiuchus