View source for Astronomy:Oph 162225-240515

{{starbox begin
| name = Oph 162225-240515
}}
{{starbox image
| image = [[File:Oph 1622 eso0629b.jpg|250px]]
| caption = Near-infrared image of the Oph 1622 binary system taken by the [[Astronomy:Very Large Telescope|Very Large Telescope]]
| credit = ESO
}}
{{starbox observe
| ra={{RA|16|22|25}}
| dec={{DEC|−24|05|15}}
| constell=Scorpius
| epoch=J2000
}}
{{Starbox astrometry
| dist_pc=140
}}
{{Starbox catalog
|names=[[Astronomy:2MASS|2MASS]]&nbsp;J16222521-2405139
}}
{{Starbox reference
|Simbad=NAME+Oph+J1622-2405|sn=Oph 1622
|Simbad2=NAME+Oph+J1622-2405+A|sn2=Oph 1622 A
|Simbad3=NAME+Oph+11+b|sn3=Oph 1622 B
}}
{{starbox end}}

'''Oph 162225-240515''', often abbreviated '''Oph 1622''', and also known as '''Oph 11''', is a pair of [[Astronomy:Brown dwarf|brown dwarf]]s that have been reported as orbiting each other. The bodies are located in the [[Astronomy:Constellation|constellation]] Scorpius and are about 400 [[Light year|light year]]s away. Mass estimates of the two objects are uncertain, but they are probably each higher than the brown-dwarf/[[Astronomy:Planet|planet]] dividing line of 13 [[Astronomy:Jupiter|Jupiter]] masses. Oph1622B is located 1.94 [[Arcsecond|arcsecond]]s from Oph1622A, at a [[Astronomy:Position angle|position angle]] of 182°.

The discovery of the pair was announced in a 2006 Science article by Ray Jayawardhana and  Valentin D. Ivanov
.<ref name="Jay">{{citation|last1=Jayawardhana | first1=R. | last2=Ivanov | first2=V. D.|date=September 2006|journal=Science|title=Discovery of a young planetary-mass binary|volume=313|issue=5791|pages=1279–1281|bibcode=2006Sci...313.1279J|doi=10.1126/science.1132128|pmid=16888101| s2cid=2822922 }}</ref> The objects were discovered using telescopes of the [[Organization:European Southern Observatory|European Southern Observatory]]'s [[Engineering:New Technology Telescope|New Technology Telescope]] in La Silla, {{wipe|Chile}}. The masses were originally reported to be lower, at 14 and 7 Jupiter masses, which would have made the smaller object a planetary-mass object, or planemo. The system was announced as the first reported binary system of objects this small. However, later observations and calculations have revised the masses upward. Close et al.<ref name=Close>{{citation|last1=Close | first1=Laird M. | last2=Zuckerman | first2=B. | last3=Song | first3=Inseok | last4=Barman | first4=Travis |date=May 2007 | journal=[[Astronomy:The Astrophysical Journal|The Astrophysical Journal]] | title=The Wide Brown Dwarf Binary Oph 1622-2405 and Discovery of a Wide, Low-Mass Binary in Ophiuchus (Oph 1623-2402): A New Class of Young Evaporating Wide Binaries?|volume=660|issue=2|pages=1492–1506|bibcode=2007ApJ...660.1492C|doi=10.1086/513417|last5=Marois|first5=Christian|last6=Rice|first6=Emily L.|last7=Siegler|first7=Nick|last8=MacIntosh|first8=Bruce|last9=Becklin|first9=E. E.| last10=Campbell | first10=Randy | last11=Lyke | first11=James E. | last12=Conrad | first12=Al | last13=Le Mignant | first13=David |arxiv = astro-ph/0608574 | s2cid=15170262 | display-authors=4 }}</ref> estimate the mass of the primary, designated Oph1622A as 12&ndash;21 times that of Jupiter and 9&ndash;20 Jupiter masses for the less massive Oph1622B, while Luhman et al.<ref name=Luhman>{{citation |last1=Luhman |first1=Kevin L. |last2=Allers |first2=Katelyn N. |last3=Jaffe |first3=Daniel T. |last4=Cushing |first4=Michael C. |last5=Williams |first5=Kurtis A. |last6=Slesnick |first6=Catherine L. |last7=Vacca |first7=William D. |date=April 2007 |journal=[[Astronomy:The Astrophysical Journal|The Astrophysical Journal]] |title=Ophiuchus 1622-2405: Not a Planetary-Mass Binary |volume=659 |issue=2 |pages=1629–1636 |url=http://www.iop.org/EJ/article/0004-637X/659/2/1629/70185.html |doi=10.1086/512539 |bibcode=2007ApJ...659.1629L |arxiv=astro-ph/0701242 |s2cid=11153196 }}</ref> assign values of 57 and 20 Jupiter masses. Despite the acronym "Oph" appearing in its name (implying that it may belong to the young Ophiuchus molecular cloud), Oph1622 is likely to be older than its originally adopted age of 1 million years. More likely, it is a member of the Upper Scorpius subgroup of the [[Astronomy:Scorpius–Centaurus association|Scorpius–Centaurus association]], which has an age of 11 million years.<ref name="Pecaut">{{Citation|author=Mark J. Pecaut|author2=Eric E. Mamajek|author3=Eric J. Bubar|name-list-style=amp|date=February 2012|title=A Revised Age for Upper Scorpius and the Star Formation History among the F-type Members of the Scorpius–Centaurus OB Association|journal=Astrophysical Journal|volume=746|issue=2|pages=154|arxiv = 1112.1695 |bibcode = 2012ApJ...746..154P |doi = 10.1088/0004-637X/746/2/154 |s2cid=118461108 }}</ref> For an adopted age of 11 million years, the system has inferred masses of 53 and 21 Jupiter masses,<ref name=Pecaut/> similar to that derived by Luhman et al.<ref name=Luhman/>

[[File:Twin Planemo System eso0629a.jpg|thumb|left|Artist's impression of Oph 1622 system with protoplanetary discs]]

The distance between the two is approximately 240 [[Astronomy:Astronomical unit|AU]]&mdash;a distance so great that Space.com wrote that "their connection is so tenuous ... that a passing star or brown dwarf could permanently separate the two objects." As such, the discovery was reported as casting doubt on the theory that such free-floating planet-like objects have been ejected from a stellar system, such an event being too violent to leave them in such a wide orbit around each other. Given their wide separation and high masses, the system is best thought of as a wide brown dwarf binary rather than a binary planetary system.<ref name=Jay/>

{{OrbitboxOnePlanet
| exoplanet = B
| mass = 21{{±|3}}<ref name=Pecaut/>
| separation = ~280
}}

==See also==
* [[Astronomy:2M1101AB|2M1101AB]]
* [[Astronomy:UScoCTIO 108|UScoCTIO 108]]
* [[Astronomy:SDSS J1416+1348|SDSS J1416+1348]]
* [[Astronomy:Brown dwarf#Binary brown dwarfs|Binary brown dwarfs]]

==References==
{{reflist|refs=

}}

==External links==
* https://www.sciencedaily.com/releases/2006/08/060804084105.htm
* http://www.spacedaily.com/reports/Astronomers_Discover_Twin_Planemos_999.html
* http://www.space.com/scienceastronomy/060803_planemo_twins.html
* http://news.bbc.co.uk/1/hi/sci/tech/5241774.stm

{{Stars of Scorpius}}

[[Category:Brown dwarfs]]
[[Category:Upper Scorpius]]



{{Sourceattribution|Oph 162225-240515}}