# Spica (Alpha Virginis)

Spica (Alpha Virginis) is a star in the constellation Virgo, magnitude 1.0.

**The Virgin’s ear of wheat — two blue stars so close that each pulls the other into an egg shape.**

Spica looks like a single blue-white point, but it is a [pair](https://astropilot.space/glossary/double-star) of hot stars whirling round each other every four days. They are so close that each pulls the other into an egg shape, and the pair brighten and fade slightly as they turn. The larger is a blue giant of more than ten solar masses, shining some 20,000 times as brightly as the Sun and pulsing every four hours or so. It is one of the nearest stars heavy enough to end as a supernova — though not for several million years.

Its name is Latin for the ear of wheat held by Virgo, the harvest maiden; on a Sumerian star list from Uruk it is ‘the Seed-Furrow’. In 2026 astronomers found a third star circling the pair and nicknamed it Arista — the bristle, or awn, of the wheat ear.

Spica (Alpha Virginis) is 250 light-years away: the light we see from it set off around 1775, around the time William Herschel discovered Uranus.

## Did you know?

- **The clue to precession.** Spica is thought to be the star that gave Hipparchus the data that led him to discover precession — the slow wobble of Earth’s axis that shifts all the stars’ positions over centuries.
- **Starlight bouncing between stars.** Each of Spica’s two stars reflects a little of the other’s light. In 2016 that made them the first stars ever to have their reflectivity measured — just a few per cent.
- **Hidden by Venus.** Venus last passed in front of Spica on 10 November 1783. The next time will be 2 September 2197.

A bright blue-white star, the brightest in Virgo, in a fairly empty part of the sky. Follow the curve of the Plough’s handle to Arcturus, then “spike to Spica”. Compare its blue-white with orange Arcturus.

## When and where to see it

It is best placed in the evening sky around May, when it crosses the meridian at about 10 pm local time (around midnight in April). It can be seen from everywhere south of 79°N and never sets south of 79°S.

At its highest it stands 29° up from 50°N, 44° up from 35°N, 79° up from the equator, 66° up from 35°S.

## Facts

- Type: Star
- Constellation: Virgo
- Designations: Alpha Virginis, α Vir, 67 Vir, HR 5056, HD 116658, HIP 65474
- Magnitude: 1.0
- Position: RA 13h 25.2m, Dec −11° 10′ (J2000)
- Spectral type: B1V
- Colour: blue-white (B−V -0.23)
- Distance: 250 light-years
- Discovered: Known since antiquity

Open AstroPilot to see when Spica (Alpha Virginis) is highest tonight from your location, how easy it is with your telescope or binoculars, and an eyepiece view. https://astropilot.space/object/spica