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: 6:55  
clear_day Transit: 12:49  
SunsetSet: 18:41 south
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All Constellations » Leo » 

Alterf - λ Leonis (lambda Leonis)

Altitude: 2.0°   Azimuth: 54.4°   Direction: North-East

Alterf, also designated as λ Leonis (lambda Leonis), is a variable giant star in the constellation of Leo.

Alterf visual magnitude is 4.31. Because of its moderate brightness, Alterf 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 Alterf:


Alterf - λ Leonis (lambda Leonis) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 2.0°
Azimuth: 54.4°
Direction: North-East

Celestial coordinates and finder chart of Alterf

Alterf 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 Alterf are provided in the following table:

09h 31m 43s
+22° 58’ 05”

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

Finder chart Alterf - λ Leonis (lambda Leonis) star
Simplified finder chart for Alterf - λ Leonis (lambda Leonis).

Visibility of Alterf 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 Alterf - λ Leonis (lambda Leonis) 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: 67.0°
Max altitude: 61.5°
Azimuth: 293.0°

Digitized Sky Survey image of Alterf

The image below is a photograph of Alterf 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 Alterf is -0.021 arcsec per year in Right Ascension and -0.033 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Alterf - λ Leonis (lambda Leonis) star
DSS2 image of Alterf. The red arrow shows the motion of Alterf during the next 10000 years (-3.50 arcmin in Right Ascension and -5.50 arcmin in declination);

Distance of Alterf from the Sun and relative movement

Alterf is distant 336.43 light years from the Sun and it is moving far from the Sun at the speed of 27 kilometers per second.

103.20 pc
336.43 ly
27 km/s
-0.021 arcsec/year
-0.033 arcsec/year

Spectral properties of Alterf

Alterf belongs to spectral class K5 and has a luminosity class of III corresponding to a giant star.


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

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

Alternative designations of Alterf

λ Leonis
(lambda Leonis)