# Peacock (Alpha Pavonis)

Peacock (Alpha Pavonis) is a star in the constellation Pavo, magnitude 1.9.

**A hot blue-white star with an RAF-issue name — and a strange shortage of deuterium.**

The star’s plain English name dates only from the late 1930s, when The Air Almanac was being prepared for Royal Air Force navigators. Alpha Pavonis had no traditional name, and the RAF wanted every star in the almanac to have one, so it was simply called Peacock — a translation of Pavo. Older names did exist: Arab astronomers paired it with Alpha Indi as al-ṣuradān, the Two Shrikes.

It is a hot blue-white [star](https://astropilot.space/glossary/star) of about six solar masses, shining 2,200 times as brightly as the Sun from a surface at 17,700 K. A close companion, never seen directly, circles it every 11.75 days. One puzzle: a star like this should keep the deuterium it was born with, yet Peacock has almost none. Perhaps it formed from deuterium-poor gas, or burned it up while it was still forming.

Peacock (Alpha Pavonis) is 180 light-years away: the light we see from it set off around 1845, around the time Neptune was discovered.

## Did you know?

- **Rediculus.** Some German sources of the 19th and early 20th centuries listed the star as ‘Rediculus’. In Marshallese it is called Likin-Buwame.
- **A young family.** Peacock probably belongs to the Tucana–Horologium association, a group of stars about 45 million years old moving through space together.

A bright blue-white star, the brightest in Pavo, the Peacock, in the far southern sky. No other bright star lies close to it, so it is easy to pick out; binoculars bring out its blue-white tint.

## When and where to see it

It is best placed in the evening sky around August, when it crosses the meridian at about 10 pm local time (around midnight in July). It can be seen from everywhere south of 33°N and never sets south of 33°S.

At its highest it stands below the horizon from 50°N, below the horizon from 35°N, 33° up from the equator, 68° up from 35°S.

## Facts

- Type: Star
- Constellation: Pavo
- Designations: Alpha Pavonis, α Pav, HR 7790, HD 193924, HIP 100751
- Magnitude: 1.9
- Position: RA 20h 25.6m, Dec −56° 44′ (J2000)
- Spectral type: B2IV
- Colour: blue-white (B−V -0.13)
- Distance: 180 light-years
- Discovered: Naked-eye star; named Peacock by HM Nautical Almanac Office in the late 1930s

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