Your guide to the Solar System and the night sky
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🌎  Observing from: Greenwich, United Kingdom [change]
🌅 Sunrise: 6:45  ☀️ Transit: 13:03  🌅 Sunset: 19:23

Achird - η Cassiopeiae (eta Cassiopeiae)

Achird, also designated as η Cassiopeiae (eta Cassiopeiae), is a multiple main-sequence star in the constellation of Cassiopeia.

Achird visual magnitude is 3.44. Because of its moderate brightness, Achird 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 Achird:

3.44
Main-sequence
Achird - η Cassiopeiae (eta Cassiopeiae) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 38°.

Celestial coordinates and finder chart of Achird

Achird 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 Achird are provided in the following table:

00h 49m 05s
+57° 48’ 56”
122.6°
-5.05°
Cassiopeia

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

Finder chart Achird - η Cassiopeiae (eta Cassiopeiae) star
Simplified finder chart for Achird - η Cassiopeiae (eta Cassiopeiae).

Visibility of Achird from your location

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

Achird - η Cassiopeiae (eta Cassiopeiae) is circumpolar and transits at 12:26 UTC (altitude: 83.7°)

Digitized Sky Survey image of Achird

The image below is a photograph of Achird 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 Achird is 1.1 arcsec per year in Right Ascension and -0.529 arcsec per year in Declination and the associated displacement for the next 100 years is represented with the red arrow.

Image of Achird - η Cassiopeiae (eta Cassiopeiae) star
DSS2 image of Achird. The red arrow shows the motion of Achird during the next 100 years (1.83 arcmin in Right Ascension and -0.88 arcmin in declination);

Distance of Achird from the Sun and relative movement

Achird is distant 19.41 light years from the Sun and it is moving far from the Sun at the speed of 9 kilometers per second.

5.95 pc
19.41 ly
9 km/s
1.1 arcsec/year
-0.529 arcsec/year

Spectral properties of Achird

Achird belongs to spectral class F9 and has a luminosity class of V corresponding to a main-sequence star.

4.57
F9V
6088K

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

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

Achird star system properties

Achird 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 Achird double sysyem:

3.44
7.44
4
11.6 arcsec

Alternative designations of Achird

Achird
η Cassiopeiae
(eta Cassiopeiae)
24 Cassiopeiae
SAO21732
SAO21732