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Star profile

3 Geminorum

Hot blue star
3D likeness based on its real data · class B · ~15,000 K

What is 3 Geminorum

3 Geminorum is a colossal oddity: a massive blue B-type star whose distance is estimated around 326,000 light-years away, far beyond the disc of the Milky Way, in the galaxy's distant halo or even outside it. If that figure —notoriously hard to pin down for such remote objects— is correct, its light departed in the depths of an ice age, when Neanderthals were still hunting mammoths across an ice-bound Europe.

Where it is and when to see it

3 Geminorum lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is December: 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.

Find it on the sky map

It opens in your browser. Free, no account, nothing to install.

The signature wall

Stelvia's sky works like a signature wall: anyone can leave their name and a message on a real star, and that signature goes up on the map for everyone to read. Signing is free.

A signature without a lock can be replaced by someone else's. The lock makes the signature permanent and lets you choose a symbolic name for the star, always shown next to the star's catalogue identifier. How the lock works

If you don't have an account yet, we'll ask for an email to confirm it's you: we send you a link and that's it, no password.

A public signature from a real person. The chosen name is a symbolic denomination within Stelvia, with no official standing or IAU recognition: the sky is not for sale and belongs to no one.

Astronomical data for 3 Geminorum

Constellation
Gemini
Apparent magnitude
5.75
Distance
326200.0 light years
Coordinates (J2000)
RA 92.433° · Dec 23.113°
Catalogue
HIP 29225 · HD 42087

A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.

Other stars in Gemini

Gemini has 74 stars in Stelvia's catalogue. Here are a few of them.

See all 74 stars in Gemini