Your Guide to the Solar System and the Night Sky
This site is free and ad-free thanks to the support of our users. If you can, please consider a donation.
public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:44  
clear_day Transit: 12:51  
SunsetSet: 18:57 south
sunny DaytimeWhat's Visible Now
All Constellations » Auriga » 


Altitude: 34.7°   Azimuth: 315.9°   Direction: North-West

HR1866 is a hypergiant star in the constellation of Auriga.

HR1866 visual magnitude is 5.73. Because of its reltive faintness, HR1866 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 HR1866:


HR1866 is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 34.7°
Azimuth: 315.9°
Direction: North-West

Celestial coordinates and finder chart of HR1866

HR1866 is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR1866 are provided in the following table:

05h 36m 35s
+54° 25’ 44”

The simplified sky map below shows the position of HR1866 in the sky:

Finder chart HR1866 star
Simplified finder chart for HR1866.

Visibility of HR1866 from your location

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

HR1866 is circumpolar and transits at 05:33 UTC (altitude: 87.1°)

Digitized Sky Survey image of HR1866

The image below is a photograph of HR1866 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 HR1866 is -0.013 arcsec per year in Right Ascension and -0.002 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of HR1866 star
DSS2 image of HR1866. The red arrow shows the motion of HR1866 during the next 10000 years (-2.17 arcmin in Right Ascension and -0.33 arcmin in declination);

Distance of HR1866 from the Sun and relative movement

HR1866 is distant 746.00 light years from the Sun and it is moving far from the Sun at the speed of 1 kilometers per second.

228.83 pc
746.00 ly
1 km/s
-0.013 arcsec/year
-0.002 arcsec/year

Spectral properties of HR1866

HR1866 belongs to spectral class M0 and has a luminosity class of III corresponding to a hypergiant star.


The red dot in the diagram below shows where HR1866 is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of HR1866. Attribution: Richard Powell / CC BY-SA

Alternative designations of HR1866