Star profile
Theta 2 Crucis
Variable starWhat is Theta 2 Crucis
Theta-2 Crucis is a spectroscopic binary at the edge of the Southern Cross, two blue stars locked in an extremely tight 3.4-day orbit. One of them is a Beta Cephei variable: it pulses with slight brightness shifts between magnitudes 4.70 and 4.74 while turning with its partner. The light arriving now set out some 854 years ago, when Pacific navigators were already using the Cross for bearings yet Europe had not formally named this knot of hot stars.
Where it is and when to see it
Theta 2 Crucis lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is April: 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.
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 Theta 2 Crucis
- Constellation
- Crux
- Apparent magnitude
- 4.72
- Distance
- 853.9 light years
- Coordinates (J2000)
- RA 181.080° · Dec -63.166°
- Catalogue
- HIP 58867 · HD 104841
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Crux
Crux has 32 stars in Stelvia's catalogue. Here are a few of them.
- AcruxAlpha 1 Crucis0.77
- MimosaBeta Crucis1.25
- GacruxGamma Crucis1.59
- HIP 623274.62
- Lambda Crucis4.62
- Iota Crucis4.69
- HIP 619664.91
- Mu 2 Crucis5.08