Your Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 4:44  
clear_day Transit: 12:57  
SunsetSet: 21:11 south
sunny DaytimeWhat's Visible Now
All Constellations » Taurus » 

Asterope - 21 Tauri

Altitude: 59.3°   Azimuth: 216.0°   Direction: South-West

Asterope, also designated as 21 Tauri , is a variable main-sequence star in the constellation of Taurus.

Asterope visual magnitude is 5.76. Because of its reltive faintness, Asterope 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 Asterope:


Asterope - 21 Tauri is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 59.3°
Azimuth: 216.0°
Direction: South-West

Celestial coordinates and finder chart of Asterope

Asterope 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 Asterope are provided in the following table:

03h 45m 54s
+24° 33’ 16”

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

Finder chart Asterope - 21 Tauri star
Simplified finder chart for Asterope - 21 Tauri.

Visibility of Asterope 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 Asterope - 21 Tauri 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: 65.4°
Max altitude: 63.1°
Azimuth: 294.6°
Asterope - 21 Tauri is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of Asterope

The image below is a photograph of Asterope 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 Asterope is 0.011 arcsec per year in Right Ascension and -0.042 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Asterope - 21 Tauri star
DSS2 image of Asterope. The red arrow shows the motion of Asterope during the next 10000 years (1.83 arcmin in Right Ascension and -7.00 arcmin in declination);

Distance of Asterope from the Sun and relative movement

Asterope is distant 386.71 light years from the Sun and it is moving far from the Sun at the speed of 9 kilometers per second.

118.62 pc
386.71 ly
9 km/s
0.011 arcsec/year
-0.042 arcsec/year

Spectral properties of Asterope

Asterope belongs to spectral class B8 and has a luminosity class of V corresponding to a main-sequence star.


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

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

Alternative designations of Asterope