Pi2 Pegasi
Single star in the constellation Pegasus
title: "Pi2 Pegasi" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["f-type-giants", "pegasus-(constellation)", "bayer-objects", "durchmusterung-objects", "flamsteed-objects", "henry-draper-catalogue-objects", "hipparcos-objects", "bright-star-catalogue-objects", "ursa-major-moving-group"] description: "Single star in the constellation Pegasus" topic_path: "general/f-type-giants" source: "https://en.wikipedia.org/wiki/Pi2_Pegasi" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Single star in the constellation Pegasus ::
| name = π2 Pegasi
| image =
|image=Pegasus constellation map.svg|alt=|float=center|width=280
|label=|position=right
|mark=Red circle.svg|mark_width=8|mark_link=π2 Peg
|x=623|y=199
| caption = Location of π2 Pegasi (circled)
| epoch = J2000.0
| constell = Pegasus
| ra =
| dec =
| appmag_v = +4.28
| type =
| class = F5 III
| b-v =
| variable =
| radial_v =
| prop_mo_ra =
| prop_mo_dec =
| parallax = 12.40
| p_error = 0.17
| parallax_footnote =
| absmag_v = 0.21
| mass = 2.48
| radius =
| luminosity =
| temperature =
| gravity =
| metal_fe =
| rotational_velocity = 139.7
| age_myr = 530
| names =
| Simbad = pi2+Peg
π2 Pegasi, Latinized as Pi2 Pegasi, is a single star in the northern constellation Pegasus. It is yellow-white in hue and visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.28. The distance to this object is approximately 263 light years based on parallax, and it is drifting further away with a radial velocity of +5 km/s. This star is an outlying member of the Ursa Major Moving Group.
::figure[src="https://upload.wikimedia.org/wikipedia/commons/8/89/Pi_Pegasi.jpg" caption="π1 Pegasi (right) and π2 Pegasi (left) in optical light"] ::
This object has a stellar classification of F5 III, matching an aging giant star that has exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. At present it has 8.5 times the radius of the Sun. The star is 530 million years old with 2.48 times the Sun's mass. It shows a high rotation rate considering its evolutionary status, with a projected rotational velocity of 140 km/s. The star has been noted as a possible variable shell star. Pi2 Pegasi is radiating 103 times the Sun's luminosity from its swollen photosphere at an effective temperature of 6,300 K.
References
References
- {{cite DR2. 1899238700116238336
- (January 2006). "Rotation- and temperature-dependence of stellar latitudinal differential rotation". Astronomy and Astrophysics.
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::