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A Complete Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 6:52  
clear_day Transit: 12:11  
SunsetSet: 17:31
sleep NighttimeWhat's Visible Now?
All Constellations » Hydra » 

ο Hydrae (omicron Hydrae)

Altitude: -9.1°   Azimuth: 223.4°   Direction: South-West

ο Hydrae is a main-sequence star in the constellation of Hydra.

ο Hydrae visual magnitude is 4.7. Because of its moderate brightness, ο Hydrae should be easily visible from locations with dark skies, while it can be barely visible, or not visible at all, from skies affected by light pollution.

The proper motion of ο Hydrae is -0.042 arcsec per year in Right Ascension and 0 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of ο Hydrae (omicron Hydrae) star
DSS2 image of ο Hydrae. The red arrow shows the motion of ο Hydrae during the next 10000 years (-7.00 arcmin in Right Ascension and 0.00 arcmin in declination);

Key facts about ο Hydrae


ο Hydrae (omicron Hydrae) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -9.1°
Azimuth: 223.4°
Direction: South-West

Celestial coordinates and finder chart of ο Hydrae

ο Hydrae is situated south of the celestial equator, as such, it is more easily visible from the southern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of ο Hydrae are provided in the following table:

11h 40m 12s
-34° 44’ 40”

The simplified sky map below shows the position of ο Hydrae in the sky:

Finder chart ο Hydrae (omicron Hydrae) star
Simplified finder chart for ο Hydrae (omicron Hydrae).

Visibility of ο Hydrae from your location

Location: Greenwich, United Kingdom edit_location_alt
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Today's ο Hydrae (omicron Hydrae) rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 124.7°
Max altitude: 3.8°
Azimuth: 235.3°

Distance of ο Hydrae from the Sun and relative movement

ο Hydrae is distant 494.69 light years from the Sun and it is moving far from the Sun at the speed of 6 kilometers per second.

151.75 pc
494.69 ly
6 km/s
-0.042 arcsec/year

Spectral properties of ο Hydrae

ο Hydrae belongs to spectral class B9 and has a luminosity class of V corresponding to a main-sequence star.


The red dot in the diagram below shows where ο Hydrae is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of ο Hydrae. Attribution: Richard Powell / CC BY-SA

Alternative designations of ο Hydrae

ο Hydrae
(omicron Hydrae)