Star profile
Omega 2 Aquarii
Hot blue starWhat is Omega 2 Aquarii
Omega-2 Aquarii is a blue-white main-sequence star in the Water Bearer. In 1953, Johnson and Morgan chose it as the photometric standard defining class B9.5V: in astronomy, its light has become a ruler. At 149 light-years, it spins on itself every ten and a half hours at 148 km per second, and ranks among the hundred strongest stellar X-ray sources within fifty parsecs of the Sun. An A-type companion shares the system at 5.7 arcseconds.
Where it is and when to see it
Omega 2 Aquarii lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is September, when it culminates around midnight.
- From London it culminates about 24° above the horizon.
- From New York it culminates about 35° above the horizon.
- From Sydney it culminates about 71° above the horizon.
It can be seen from anywhere south of 75° N.
It ranks no. 20 in brightness among the 99 stars of Aquarius in our catalogue. To find it, start from Sadalsuud, the brightest: it lies about 33° away (a fist at arm's length covers about 10°).
The light you see today left it about 150 years ago.
It opens in your browser. Free, no account, nothing to install.
Leave your signature on Omega 2 Aquarii
Your name and a message go up on the map for everyone to read. Signing is free.
Without a lock, someone else can replace your signature. How the lock works
We'll ask for an email to confirm it's you, 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 Omega 2 Aquarii
- Constellation
- Aquarius
- Apparent magnitude
- 4.49
- Distance
- 148.5 light years
- Coordinates (J2000)
- RA 355.681° · Dec -14.545°
- Catalogue
- HIP 116971 · HD 222661
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Aquarius
Aquarius has 99 stars in Stelvia's catalogue. Here are a few of them.
- SadalsuudBeta Aquarii2.90
- SadalmelikAlpha Aquarii2.95
- SkatDelta Aquarii3.27
- Psi 2 Aquarii4.41
- 3 Aquarii4.43
- 86 Aquarii4.48
- Nu Aquarii4.50
- BundaXi Aquarii4.68