Delta Andromedae
{{short description|Multiple star system in the constellation Andromeda}}
{{Starbox begin
| name = δ Andromedae
}}
{{Starbox image
| image=
{{Location mark
|image=Andromeda constellation map.svg|alt=|float=center|width=260
|label=|position=right
|mark=Red circle.svg|mark_width=10|mark_link=δ Andromedae
|x=622|y=698
}}
|caption=Location of δ Andromedae (circled)
}}
{{Starbox observe
| epoch = J2000.0
| constell = Andromeda
| dec = {{DEC|+30|51|39.6783}}
}}
{{Starbox character
| class = K3 III + {{nowrap|K4 ± 2}}
}}
{{Starbox astrometry
| radial_v = {{val|−9.88|0.15}}
| parallax = 30.91
| p_error = 0.15
}}
{{Starbox orbit
| period_unitless = 15,000 d
| eccentricity = {{val|0.34|0.14}}
| periastron = 2415568 JD
| periarg_primary = {{val|356.1|5.2}}
| k1 = {{val|4.0|2.7}}
}}
{{Starbox detail
| component1 = δ And Aa
| radius = {{val|13.6|0.3}}
| luminosity = {{val|68|4}}
| temperature = {{val|4315|9|fmt=commas}}
| metal_fe = 0.04
| age_gyr = 3.2
| component2 = δ And Ab
| mass2 = 0.6–0.8
}}
{{Starbox catalog
| names = {{odlist | B=δ And, Delta Andromedae, Delta And | F=31 Andromedae, 31 And | BD=+30 91 | FK5=20 | HD=3627 | HIP=3092 | HR=165 | NSV=15142 | SAO=54058 | PPM=65514 | USNO=790 | WDS=00393+3052A }}
}}
{{Starbox reference
| Simbad=del+and
}}
{{Starbox end}}
Delta Andromedae is a triple star system in the northern constellation of Andromeda. Its identifier is a Bayer designation that is Latinized from δ Andromedae, and abbreviated Delta And or δ And, respectively. The system is visible to the naked eye as a point of light with a combined apparent visual magnitude of 3.28. Based upon parallax measurements, it is located at a distance of approximately {{Convert|105.5|ly|pc|abbr=off|lk=on}} from the Sun. The system is drifting closer with a radial velocity of −10 km/s.
In Chinese, {{lang|zh|奎宿}} ({{lang|zh-Latn|Kuí Sù}}), meaning Legs (asterism), refers to an asterism consisting of δ Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ι Piscium, ε Andromedae, π Andromedae, ν Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ1 Piscium. Consequently, the Chinese name for δ Andromedae itself is {{lang|zh|奎宿五}} ({{lang|zh-Latn|Kuí Sù wǔ}}, {{langx|en|the Fifth Star of Legs}}.){{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0605/ap060519.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日] {{Webarchive|url=https://web.archive.org/web/20160303170659/http://aeea.nmns.edu.tw/2006/0605/ap060519.html |date=2016-03-03 }} Apart from its Bayer designation, it was also given the title Delta by Elijah H. Burritt in his star atlas.
This is a long-period spectroscopic binary with an orbital period of approximately 15,000 days (41 years). The primary of the spectroscopic binary, component Aa, has a stellar classification of K3 III, indicating that it is an aging giant star. It most likely evolved from a F-type main sequence star after consuming the hydrogen at its core. The secondary, component Ab, is a relatively faint K-type dwarf, which has been imaged using a stellar coronagraph. The pair have a physical separation of {{val|11.55|0.13|ul=AU}}. The system has two companions, the closest of which is most likely an orbiting red dwarf of class M3 with a separation of at least 900 astronomical units.
An excess of infrared emission from δ Andromedae suggested that it may be surrounded by a shell of dust. In 2003 it was determined that this is more likely a circumstellar debris disk.
References
{{Reflist|30em|refs=
{{citation | title=Comparing the Ca ii H and K Emission Lines in Red Giant Stars
| postscript=. | display-authors=1 | last1=Ryon | first1=Jenna
| last2=Shetrone | first2=Matthew D. | last3=Smith | first3=Graeme H.
| journal=Publications of the Astronomical Society of the Pacific
| volume=121 | issue=882 | page=842 | date=August 2009
| doi=10.1086/605456 | bibcode=2009PASP..121..842R |arxiv = 0907.3346 | s2cid=17821279 }}
{{citation | url=http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=V/50/catalog&recno=165 | title=HR 165, database entry | work=The Bright Star Catalogue | edition=5th (Preliminary Version) | first1=D. | last1=Hoffleit | first2=W. H. | last2=Warren Jr. | publisher=CDS }} ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]. Accessed on line August 28, 2008.
| title=Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity
| last1=Massarotti | first1=Alessandro | last2=Latham | first2=David W.
| last3=Stefanik | first3=Robert P. | last4=Fogel | first4=Jeffrey
| display-authors=1 | journal=The Astronomical Journal
| volume=135 | issue=1 | pages=209–231 | date=January 2008
| doi=10.1088/0004-6256/135/1/209 | doi-access=free
| bibcode=2008AJ....135..209M | postscript=. }}
{{citation | title=Delta Andromedae (K3 III) - an IRAS source with an unusual ultraviolet spectrum | first1=P. G. | last1=Judge | first2=C. | last2=Jordan | first3=M. | last3=Rowan-Robinson | journal=Monthly Notices of the Royal Astronomical Society | volume=224 | date=January 1, 1987 | pages=93–106 | bibcode=1987MNRAS.224...93J | doi = 10.1093/mnras/224.1.93 | doi-access=free }}.
{{citation | title=Photocentric orbits from a direct combination of ground-based astrometry with Hipparcos I. Comparison with known orbits | first1=G.A. | last1=Gontcharov | first2=O. V. | last2=Kiyaeva | journal=Astronomy and Astrophysics | volume=391, 647-657 | date=2002 | page=647 | bibcode=2002A&A...391..647G |doi = 10.1051/0004-6361:20020896 | doi-access=free }}.
{{cite simbad | title=del And | access-date=August 28, 2008 }}
{{citation|title=Entry 00393+3052 |url=http://ad.usno.navy.mil/wds/wdsnewframe1.html |work=The Washington Double Star Catalog |publisher=United States Naval Observatory |access-date=2008-08-28 |url-status=dead |archive-url=https://web.archive.org/web/20080412091309/http://ad.usno.navy.mil/wds/wdsnewframe1.html |archive-date=2008-04-12 }}
Richard Hinckley Allen (1899) [https://books.google.com/books?id=5xQuAAAAIAAJ Star-names and Their Meanings], p. 38.
{{citation | first1=James B. | last1=Kaler | title=DELTA AND (Delta Andromedae) | work=Stars | publisher=University of Illinois | url=http://stars.astro.illinois.edu/sow/deltaand.html | access-date=2012-01-23 }}
{{citation | display-authors=1 |title=Resolving the Delta Andromedae Spectroscopic Binary with Direct Imaging | first1=M. | last1=Bottom | first2=J. |last2=Kuhn| first3=B. |last3=Mennesson| journal=The Astrophysical Journal | volume=809 | issue=1 | date=August 4, 2015 |page=11 | bibcode=2015ApJ...809...11B | doi = 10.1088/0004-637X/809/1/11 |arxiv=1506.07517 |s2cid=32786144 }}.
| 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 | bibcode=2008MNRAS.389..869E
| arxiv=0806.2878 | s2cid=14878976 | postscript=. }}
| title=The Chromospheric Radiation on the Circumstellar Shell of δ Andromedae
| last=Wirsich | first=J.
| journal=The Astrophysical Journal
| volume=502 | issue=2 | pages=909–917 | date=August 1998
| doi=10.1086/305935 | bibcode=1998ApJ...502..909W | s2cid=120614789
| doi-access=free}}
}}
External links
- [http://www.eso.org/public/outreach/eduoff/cas/cas2002/cas-projects/france_andromeda_1/ The Constellation Andromeda: The Chained Maiden] {{Webarchive|url=https://web.archive.org/web/20210213010419/http://www.eso.org/public/outreach/eduoff/cas/cas2002/cas-projects/france_andromeda_1/ |date=2021-02-13 }}, web page, European Southern Observatory outreach.
- [http://aladin.u-strasbg.fr/AladinPreview?-c=00+39+19.6758%2B30+51+39.686&ident=NSV+15142&submit=Aladin+previewer Image Delta Andromedae]
{{Stars of Andromeda}}
{{DEFAULTSORT:Delta Andromedae}}
Category:K-type main-sequence stars
Category:M-type main-sequence stars
Category:Spectroscopic binaries