28 Aquarii

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title: "28 Aquarii" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["aquarius-(constellation)", "flamsteed-objects", "k-type-giants", "henry-draper-catalogue-objects", "bright-star-catalogue-objects", "durchmusterung-objects", "hipparcos-objects"] description: "Star in the constellation Aquarius" topic_path: "general/aquarius-constellation" source: "https://en.wikipedia.org/wiki/28_Aquarii" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Star in the constellation Aquarius ::

| epoch=J2000 | constell=Aquarius | ra= | dec= | appmag_v=5.597 | class=K2III | b-v=+1.28 | u-b=+1.40 | radial_v= | prop_mo_ra=+6.22 | prop_mo_dec=−11.05 | parallax=5.7956 | p_error=0.1557 | parallax_footnote= | absmag_v = | source= | radius= | luminosity= | gravity=2.3 | temperature=4,361 | mass=1.47 | age_gyr=2.9 | names= | Simbad=28+Aqr

28 Aquarii is a single star located about 560 light years away from the Sun in the zodiac constellation of Aquarius. 28 Aquarii is the Flamsteed designation. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.6. This object is moving further from the Earth with a heliocentric radial velocity of +8.1 km/s.

This 2.9 billion year old object is an aging giant star with a stellar classification of K2 III. After exhausting the hydrogen at its core, this star evolved off the main sequence and has now expanded to 28 times the Sun's radius. It has 1.47 times the mass of the Sun and is radiating 258 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,361 K.

References

| title=A catalogue of multiplicity among bright stellar systems | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A. | journal=Monthly Notices of the Royal Astronomical Society | volume=389 | issue=2 | pages=869 | date=2008 | doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | arxiv=0806.2878 | bibcode=2008MNRAS.389..869E | s2cid=14878976 | postscript=. }}

References

1. {{cite DR2. 2680711298157124736
2. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics.
3. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey.
4. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory.
5. (2002). "Radial Velocities for 889 Late-Type Stars". The Astrophysical Journal Supplement Series.
6. van Leeuwen, F.. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics.
7. (2016). "Red giant masses and ages derived from carbon and nitrogen abundances". Monthly Notices of the Royal Astronomical Society.
8. "* 28 Aqr".

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