Unukalhai - α Serpentis (alpha Serpentis)

Above the horizon. Rise: 16:28 | Tran: 22:49 | Set: 5:14

Alt: 53.88° Az: 172.38° Direction: South

Unukalhai, also designated as α Serpentis (alpha Serpentis), is a multiple giant star of spectral class K2 in the constellation of Serpens.

Unukalhai visual magnitude is 2.65. Because of its brightness, Unukalhai is clearly visible to the naked eye when observed from locations with dark skies, and should be also quite easily visible from light polluted areas.

Image of Unukalhai - α Serpentis (alpha Serpentis) star

DSS2 image of Unukalhai. The red arrow shows the motion of Unukalhai during the next 1000 years (2.28 arcmin in Right Ascension and 0.78 arcmin in declination);

Celestial Coordinates

Apparent

Right Ascension 15h 45m 31s

Declination +06° 20’ 47”

Hour Angle 23h 41m 57s

Sidereal Time 15h 27m 28s

J2000

Right Ascension 15h 44m 16s

Declination +06° 25’ 32”

Galactic Coordinates

Galactic Longitude 14.2°

Galactic Latitude 44.08°

Finder Chart

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Finder chart for Unukalhai - α Serpentis (alpha Serpentis).

Magnitude, Color, Spectral Class

Color ⬤

Magnitude 2.65

Class Giant

Absolute magnitude 0.89

Spectral Type K2III

Color Index (B-V) 1.17

Temperature 4368K

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

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

Star System Properties

Unukalhai is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the Unukalhai double sysyem:

Main star magnitude 2.65

Secondary star magnitude 10.95

Magnitude difference 8.3

Separation 58.2 arcsec

Distance, Radial Speed, Proper Motion

Unukalhai is distant 73.19 light years from the Sun and it is moving far from the Sun at the speed of 3 kilometers per second.

Distance (parsec) 22.45

Distance (light year) 73.19

Radial Speed 3 km/s

Proper Motion RA 0.137 arcsec/y

Proper Motion Dec 0.047"/y

Alternative Designations

Proper Name Unukalhai

Bayer designation α Serpentis
(alpha Serpentis)

Flamsteed designation 24 Serpentis

Henry Draper Catalogue HD140573

SAO Catalogue SAO121157

Hipparcos Catalogue HIP77070

Durchmusterung Catalogue BD+06 3088

Gliese Catalogue Gl 596.2

FK5 Catalogue 582

Aitken Double Star Catalogue ADS9765

Visibility from Your Location

Today's Unukalhai - α Serpentis (alpha Serpentis) rise, transit and set times from Lladó, Spain are the following (all times relative to the local timezone Europe/Madrid):

Azimuth: 83.7° RISE 16:28

Max altitude: 54.1° TRANSIT 22:49

Azimuth: 276.3° SET 5:14

Name:	Lladó, Spain
Latitude:	42° 14' 51.7" N
Longitude:	2° 48' 49.4" E
Timezone:	Europe/Madrid

Set Location

Other stars in Serpens