Lambda Mensae
Encyclopedia
Lambda Mensae is a medium mass orange giant star
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...

 in the southern constellation Mensa
Mensa (constellation)
Mensa is a constellation in the southern sky, created in the 18th century. Its name is Latin for table. It covers a keystone-shaped wedge of sky stretching from approximately 4h to 7.5h of right ascension, and −71 to −85.5 degrees of declination. Other than the south polar constellation...

. Though it has the designation
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name...

 Lambda
Lambda
Lambda is the 11th letter of the Greek alphabet. In the system of Greek numerals lambda has a value of 30. Lambda is related to the Phoenician letter Lamed . Letters in other alphabets that stemmed from lambda include the Roman L and the Cyrillic letter El...

, it is actually the twenty-fourth brightest star in the constellation and not the eleventh. Parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...

 calculations put this star at a distance of 385 light-years or 118 parsecs. From this and its apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...

 of 6.54, it can be said that this star has a luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...

 of 27 times that of the Sun (40 times bolometric). The mass of the star is estimated at 1.5 to 3 solar mass
Solar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...

es and it has a radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...

 of 7.49 solar radii.
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