55 Orionis

55 Orionis is a variable sub-giant star in the constellation of Orion.

55 Orionis visual magnitude is 5.35. Because of its reltive faintness, 55 Orionis should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about 55 Orionis:

Color of 55 Orionis ⬤

Magnitude of 55 Orionis 5.35

Class Sub-giant

VISIBILITY RIGHT NOW

55 Orionis is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -4.8°
Azimuth: 96.1°
Direction: East

Celestial coordinates and finder chart of 55 Orionis

55 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 55 Orionis are provided in the following table:

Right Ascension J2000 05h 51m 21s

Declination J2000 -07° 31’ 05”

Galactic Longitude 212.89°

Galactic Latitude -16.76°

Constellation Orion

The simplified sky map below shows the position of 55 Orionis in the sky:

Simplified finder chart for 55 Orionis.

Visibility of 55 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 55 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: 97.5° RISE 8:40

Max altitude: 31.0° TRANSIT 14:00

Azimuth: 262.5° SET 19:20

RIGHT NOW 55 Orionis is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 55 Orionis

The image below is a photograph of 55 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 55 Orionis is -0.001 arcsec per year in Right Ascension and 0.003 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.

DSS2 image of 55 Orionis. The red arrow shows the motion of 55 Orionis during the next 100000 years (-1.67 arcmin in Right Ascension and 5.00 arcmin in declination);

Distance of 55 Orionis from the Sun and relative movement

55 Orionis is distant 1,680.41 light years from the Sun and it is moving far from the Sun at the speed of 20 kilometers per second.

Distance (parsec) 515.46 pc

Distance (light year) 1,680.41 ly

Heliocentric radial velocity 20 km/s

Proper Motion RA -0.001 arcsec/year

Proper Motion Dec 0.003 arcsec/year

Spectral properties of 55 Orionis

55 Orionis belongs to spectral class B2 and has a luminosity class of IV corresponding to a sub-giant star.

Absolute magnitude -3.21

Spectral Type B2IV

Color Index (B-V) -0.2

Temperature of 55 Orionis 13585K

The red dot in the diagram below shows where 55 Orionis is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of 55 Orionis. Attribution: Richard Powell / CC BY-SA

Alternative designations of 55 Orionis

Flamsteed designation 55 Orionis

Henry Draper Catalogue HD39291

SAO Catalogue SAO132591

Hipparcos Catalogue HIP27658

Durchmusterung Catalogue BD-07 1187

FK5 Catalogue 2442

General Catalogue of Variable Stars 2677

In Evidence

Other stars in Orion