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: 4:52  
clear_day Transit: 12:55  
SunsetSet: 20:59 south
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Breakng! newly discovered Supernova 2023ixf in the Pinwheel Galaxy is the closest supernova observed in the latest decade. It can become bright enough to be visible by amateur astronomers. Check out information and detailed finder chart.
All Constellations » Puppis » 

21 Puppis

21 Puppis is a variable main-sequence star in the constellation of Puppis.

21 Puppis visual magnitude is 6.16. Because of its reltive faintness, 21 Puppis 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 21 Puppis:

21 Puppis is above the horizon from Greenwich, United Kingdom edit_location_alt. Altitude: 8°.

Celestial coordinates and finder chart of 21 Puppis

21 Puppis 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 21 Puppis are provided in the following table:

08h 17m 23s
-16° 17’ 06”

The simplified sky map below shows the position of 21 Puppis in the sky:

Finder chart 21 Puppis star
Simplified finder chart for 21 Puppis.

Visibility of 21 Puppis 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 21 Puppis 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: 106.3°
Max altitude: 22.2°
Azimuth: 253.7°
21 Puppis is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 21 Puppis

The image below is a photograph of 21 Puppis 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 21 Puppis is -0.02 arcsec per year in Right Ascension and -0.008 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 21 Puppis star
DSS2 image of 21 Puppis. The red arrow shows the motion of 21 Puppis during the next 10000 years (-3.33 arcmin in Right Ascension and -1.33 arcmin in declination);

Distance of 21 Puppis from the Sun and relative movement

21 Puppis is distant 857.89 light years from the Sun

263.16 pc
857.89 ly
-0.02 arcsec/year
-0.008 arcsec/year

Spectral properties of 21 Puppis

21 Puppis belongs to spectral class A2 and has a luminosity class of V corresponding to a main-sequence star.


The red dot in the diagram below shows where 21 Puppis is situated in the Hertzsprungā€“Russell diagram.

HR Diagram
H-R diagram showing the position of 21 Puppis. Attribution: Richard Powell / CC BY-SA

Alternative designations of 21 Puppis