Star profile

Rho Hydrae

3D likeness based on its real data · class A · ~8,500 K

What is Rho Hydrae

Rho Hydrae shines along the serpentine body of Hydra, the largest constellation in the sky. It is a white subgiant, young and restless: spinning at 128 km/s, three solar masses, shining with two hundred and forty-two times the Sun's luminosity. A faint distant companion completes the system, three and a half centuries away.

Where it is and when to see it

Rho 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 44° above the horizon.
From New York it culminates about 55° above the horizon.
From Sydney it culminates about 50° above the horizon.

It can be seen from anywhere north of 84° S.

It ranks no. 18 in brightness among the 121 stars of Hydra in our catalogue. To find it, start from Alphard, the brightest: it lies about 17° away (a fist at arm's length covers about 10°).

The light you see today left it about 350 years ago.

Find it on the sky map

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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 Rho Hydrae

Constellation: Hydra
Apparent magnitude: 4.35
Distance: 354.2 light years
Coordinates (J2000): RA 132.108° · Dec 5.838°
Catalogue: HIP 43234 · HD 75137

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Other stars in Hydra

Hydra has 121 stars in Stelvia's catalogue. Here are a few of them.

See all 121 stars in Hydra