54 Eridani
{{short description|Star in the constellation Eridanus}}
{{Starbox begin}}
{{Starbox image
| image = 250px
| caption = A light curve for DM Eridani, plotted from data published by Tabur et al. (2009)
}}
{{Starbox observe
| epoch = J2000.0
| constell = Eridanus
| dec = {{DEC|-19|40|17.3723}}
}}
{{Starbox character
| type = asymptotic giant branch
| variable = SRb
}}
{{Starbox astrometry
| radial_v = {{Val|−32.9|0.8}}
| parallax = 8.2063
| p_error = 0.2709
}}
{{Starbox detail
| mass =
| gravity =
| luminosity = {{Val|1021|33|38|fmt=commas}}
| temperature = {{Val|3915|190|293|fmt=commas}}
| metal_fe =
| rotational_velocity =
| age_gyr =
}}
{{Starbox catalog
| names = {{odlist | V=DM Eridani | BD=-19°988 | HD=29755 | HIP=21763 | HR=1496 | SAO=149818 | WDS=J04404-1940 | GC=5695 }}
}}
{{Starbox reference
| Simbad=54+Eri
}}
{{Starbox end}}
54 Eridani is a suspected astrometric binary star system located around 400 light years from the Sun in the equatorial constellation of Eridanus. It is visible to the naked eye as a faint, reddish hued star with a baseline apparent visual magnitude of 4.32. The object is moving closer to the Earth with a heliocentric radial velocity of −33 km/s.
The variability of 54 Eridani was announced by Benjamin Apthorp Gould in his Uranometria Argentina, published in 1879. But it was not given its variable star designation, DM Eridani, until nearly 100 years later, in 1973. The visible component is an aging red giant star, currently on the asymptotic giant branch, with a stellar classification of M3/4 III. It is a semiregular variable star of subtype SRb, ranging in magnitude from 4.28 down to 4.36. The star has pulsation periods of 18.8 and 45.5 days, each with an amplitude of 0.019 in magnitude. With the hydrogen at its core exhausted, the star has expanded to around 69 times the Sun's radius and it is radiating 1,021 times the luminosity of the Sun from its swollen photosphere at an effective temperature of 3,915 K.
It was the second-brightest star in the obsolete constellation of Sceptrum Brandenburgicum after 53 Eridani.
References
{{reflist|30em|refs=
{{cite DR2|2977433305688884224}}
{{cite simbad | title=54 Eri | access-date=2019-05-28 }}
| last1=Gould | first1=Benjamin Apthorp
| title=Uranometria Argentina: Brightness and position of every fixed star, down to the seventh magnitude, within one hundred degrees of the South Pole; with atlas | journal=Resultados del Observatorio Nacional Argentino
|date=1879
| volume=1
| page=162, 273 | bibcode=1879RNAO....1....1G
| url=https://articles.adsabs.harvard.edu/pdf/1879RNAO....1D...1G | access-date=8 December 2024}}
| last1=Van Leeuwen | first1=F.
| title=Validation of the new Hipparcos reduction
| journal=Astronomy and Astrophysics
| volume=474 | issue=2 | pages=653–664 | year=2007
| arxiv=0708.1752 | bibcode=2007A&A...474..653V
| doi=10.1051/0004-6361:20078357 | s2cid=18759600
| postscript=. }}
| last1=Kukarkin | first1=B. V. | last2=Kholopov | first2=P. N. | last3=Kukarkina | first3=N. P.
| last4=Perova | first4=N. B. | title=59th Name-List of Variable Stars
| journal=Information Bulletin on Variable Stars | date=October 1973 | volume=834 | issue=1–22
| page=1 | bibcode=1973IBVS..834....1K | url=https://ibvs.konkoly.hu/pub/ibvs/0801/0834.pdf
| access-date=8 December 2024}}
| title=XHIP: An extended hipparcos compilation
| last1=Anderson | first1=E. | last2=Francis | first2=Ch.
| journal=Astronomy Letters | postscript=.
| volume=38 | issue=5 | pages=331 | year=2012
| bibcode=2012AstL...38..331A | arxiv=1108.4971
| doi=10.1134/S1063773712050015 | s2cid=119257644 }}
| last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
| title=A catalogue of multiplicity among bright stellar systems
| journal=Monthly Notices of the Royal Astronomical Society
| volume=389 | issue=2 | pages=869–879 | date=September 2008
| doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | postscript=.
| bibcode=2008MNRAS.389..869E |arxiv = 0806.2878 | s2cid=14878976 }}
| last1=Tabur | first1=V. | last2=Bedding | first2=T. R.
| last3=Kiss | first3=L. L. | last4=Moon | first4=T. T.
| last5=Szeidl | first5=B. | last6=Kjeldsen | first6=H.
| title=Long-term photometry and periods for 261 nearby pulsating M giants
| display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society
| volume=400 | issue=4 | pages=1945–1961 | date=December 2009
| doi=10.1111/j.1365-2966.2009.15588.x | doi-access=free | postscript=.
| bibcode=2009MNRAS.400.1945T | arxiv=0908.3228 | s2cid=15358380 }}
| last1=Houk | first1=Nancy | last2=Smith-Moore | first2=M.
| title=Michigan catalogue of two-dimensional spectral types for the HD stars
| volume=4 | location=Ann Arbor | year=1978
| publisher=Dept. of Astronomy, University of Michigan
| bibcode=1988mcts.book.....H | postscript=. }}
| display-authors=1 | last1=Samus | first1=N. N.
| last2=Kazarovets | first2=E. V. | last3=Durlevich | first3=O. V.
| last4=Kireeva | first4=N. N. | last5=Pastukhova | first5=E. N.
| title=General Catalogue of Variable Stars
| version=5.1 | journal=Astronomy Reports
| year=2017 | volume=61 | issue=1 | pages=80–88
| bibcode=2017ARep...61...80S | postscript=. | doi=10.1134/S1063772917010085 | s2cid=125853869 }}
| last1=Eggen | first1=Olin J.
| title=Asymptotic giant branch stars near the sun
| journal=Astronomical Journal | postscript=.
| volume=104 | issue=1 | pages=275–313 | date=July 1992
| doi=10.1086/116239 | bibcode=1992AJ....104..275E }}
}}
{{Stars of Eridanus}}
{{DEFAULTSORT:54 Eridani}}
Category:Asymptotic-giant-branch stars
Category:Eridanus (constellation)
Category:Durchmusterung objects