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EntityQ584300· pop 30· linked from 182 articles

Also known as V342 Pegasi

star in the constellation Pegasus

Key facts

Constellation
Pegasus
Right ascension
23 07 28.7157
Declination
+21 ° 08 ′ 03.311 ″
Evolutionary stage
main sequence
Spectral type
F0kA5mA5V λ Boo
U b color index
−0.04
Variable type
γ Dor

via Wikipedia infobox

Wikidata facts

Instance of
variable star
Constellation
Pegasus
Distance from Earth
40.88
Diameter
2004400
Radius
1.44
Mass
1.56
Variable-star type
Gamma Doradus variable
Image
HR 8799 Debris Disk.jpg
Show 20 more facts
spectral class
F0VmA4 lambda Boo
catalog code
WDS J23075+2108Aa
luminosity
4.92
topic's main category
Category:HR 8799
Commons category
HR 8799
parallax
24.462
epoch
J2000.0
absolute magnitude
3
topic has template
Template:HR 8799
right ascension component of proper motion
108.284
declination component of proper motion
-50.04
right ascension
346.86964883731
declination
21.13425299097
apparent magnitude
5.240
stellar rotational velocity
50.5
radial velocity
-12.60
age estimated by a dating method
0.06
metallicity
-1.5616
effective temperature
7301
surface gravity
13200
Sources (2)

via Wikidata · CC0

~15 min read

Encyclopedic overview

HR 8799 is a roughly 42 million-year-old main-sequence star located 133.3 light-years (40.9 parsecs) away from Earth in the constellation of Pegasus. It has roughly 1.4 times the Sun's mass and 5 times its luminosity. It is part of a system that also contains a debris disk and at least four massive planets. These planets were the first exoplanets whose orbital motion was confirmed by direct imaging. The star is a Gamma Doradus variable: its luminosity changes because of non-radial pulsations of its surface. The star is also classified as a Lambda Boötis star, which means its surface layers are depleted in iron peak elements. It is the only known star which is simultaneously a Gamma Doradus variable, a Lambda Boötis type, and a Vega-like star (a star with excess infrared emission caused by a circumstellar disk).

Location

Excerpted from Wikipedia’s “Q584300” article, available under the CC BY-SA 4.0 licence.