Star profile
Theta Hydrae
Hot blue starWhat is Theta Hydrae
θ Hydrae is a blue-white sun at 114 light-years, far hotter and younger than our own. It shines along one of the Serpent's bends with the near-violet glow of B-class stars — those that burn twice as fast and die long before suns like ours. It is the promise of a brief and dazzling stellar life, lit above the longest constellation in the sky.
Where it is and when to see it
Theta Hydrae lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is February, when it culminates around midnight.
- From London it culminates about 41° above the horizon.
- From New York it culminates about 52° above the horizon.
- From Sydney it culminates about 54° above the horizon.
It can be seen from anywhere north of 88° S.
It ranks no. 10 in brightness among the 121 stars of Hydra in our catalogue. To find it, start from Alphard, the brightest: it lies about 11° away (a fist at arm's length covers about 10°).
The light you see today left it about 110 years ago.
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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 Hydrae
- Constellation
- Hydra
- Apparent magnitude
- 3.89
- Distance
- 113.5 light years
- Coordinates (J2000)
- RA 138.591° · Dec 2.314°
- Catalogue
- HIP 45336 · HD 79469
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Other stars in Hydra
Hydra has 121 stars in Stelvia's catalogue. Here are a few of them.
- AlphardAlpha Hydrae1.99
- Gamma Hydrae2.99
- Zeta Hydrae3.11
- Xi Hydrae3.54
- Lambda Hydrae3.61
- Mu Hydrae3.83
- UkdahIota Hydrae3.90
- HIP 413073.91