ρ Orionis (rho Orionis)

Altitude: -29.6° Azimuth: 323.6° Direction: North-West

ρ Orionis is a variable and multiple hypergiant star in the constellation of Orion.

ρ Orionis visual magnitude is 4.46. Because of its moderate brightness, ρ Orionis should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.

The table below summarizes the key facts about ρ Orionis:

Color of ρ Orionis ⬤

Magnitude of ρ Orionis 4.46

Class Hypergiant

VISIBILITY RIGHT NOW

ρ Orionis (rho Orionis) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -29.6°
Azimuth: 323.6°
Direction: North-West

Celestial coordinates and finder chart of ρ Orionis

ρ Orionis is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of ρ Orionis are provided in the following table:

Right Ascension J2000 05h 13m 17s

Declination J2000 +02° 51’ 39”

Galactic Longitude 198.52°

Galactic Latitude -20.27°

Constellation Orion

The simplified sky map below shows the position of ρ Orionis in the sky:

Finder chart ρ Orionis (rho Orionis) star

Simplified finder chart for ρ Orionis (rho Orionis).

Visibility of ρ Orionis 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 ρ Orionis (rho Orionis) 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: 87.1° RISE 23:26

Max altitude: 41.4° TRANSIT 5:42

Azimuth: 272.9° SET 11:54

Digitized Sky Survey image of ρ Orionis

The image below is a photograph of ρ Orionis from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of ρ Orionis is 0.001 arcsec per year in Right Ascension and -0.006 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.

DSS2 image of ρ Orionis. The red arrow shows the motion of ρ Orionis during the next 100000 years (1.67 arcmin in Right Ascension and -10.00 arcmin in declination);

Distance of ρ Orionis from the Sun and relative movement

ρ Orionis is distant 343.52 light years from the Sun and it is moving far from the Sun at the speed of 41 kilometers per second.

Distance (parsec) 105.37 pc

Distance (light year) 343.52 ly

Heliocentric radial velocity 41 km/s

Proper Motion RA 0.001 arcsec/year

Proper Motion Dec -0.006 arcsec/year

Spectral properties of ρ Orionis

ρ Orionis belongs to spectral class K0 and has a luminosity class of III corresponding to a hypergiant star.

Absolute magnitude -0.65

Spectral Type K0III

Color Index (B-V) 1.19

Temperature of ρ Orionis 4328K

The red dot in the diagram below shows where ρ Orionis is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of ρ Orionis. Attribution: Richard Powell / CC BY-SA

ρ Orionis star system properties

ρ Orionis is a visual double star which can be observed with the help of small or medium telescopes. The table below shows key information about the ρ Orionis double sysyem:

Main star magnitude 4.46

Secondary star magnitude 8.36

Magnitude difference 3.9

Separation 6.9 arcsec

Alternative designations of ρ Orionis

Bayer designation ρ Orionis
(rho Orionis)

Flamsteed designation 17 Orionis

Henry Draper Catalogue HD33856

SAO Catalogue SAO112528

Hipparcos Catalogue HIP24331

Durchmusterung Catalogue BD+02 888

General Catalogue of Variable Stars 1872

Aitken Double Star Catalogue ADS3797

Support us

In Evidence

Other stars in Orion