View source for Visible Multi Object Spectrograph

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{{Short description|Wide field imager and multi-object spectrograph at the VLT in Chile}}
[[File:Vimos-VLT.jpg|thumb|265px|VIMOS attached to VLT's ''Melipal'' (UT3)]]

The '''Visible Multi-Object Spectrograph''' ('''VIMOS''') is a wide field imager and a multi-object [[spectrograph]] installed at the [[European Southern Observatory]]'s [[Very Large Telescope]] (VLT), in Chile. The instrument used for deep astronomical surveys delivers visible images and spectra of up to 1,000 galaxies at a time.<ref name="vimos">{{cite web |url=https://www.eso.org/sci/facilities/paranal/instruments/vimos.html |title=VIMOS – Visible Multi Object Spectrograph (Summary) |work=ESO |date=19 December 2013 |access-date=2 August 2015}}</ref><ref>{{cite web |url=https://www.eso.org/sci/facilities/paranal/instruments/vimos/overview.html |title=VIMOS – General Description (Overview) |work=ESO |date=23 March 2013 |access-date=2 August 2015}}</ref> VIMOS images four rectangular areas of the sky, 7 by 8 [[arcminutes]] each, with gaps of 2 arcminutes between them.<ref name="vimos" /> Its [[principal investigator]] was [[Olivier Le Fèvre]].

The Franco-Italian instrument operates in the visible part of the spectrum from 360 to 1000 [[nanometer]]s (nm). In the conceptual design phase, the [[Multi-Object Spectrometer|multi-object spectrograph]] then called VIRMOS included an additional instrument, NIMOS, operating in the near-infrared spectrum of 1100–1800&nbsp;nm.<ref>{{cite web |url=https://www.eso.org/sci/publications/messenger/archive/no.91-mar98/messenger-no91-16-17.pdf |title=VIMOS and NIRMOS: Status Report |work=ESO |format=PDF |date=March 1998}}</ref>

Operating in the three different observation modes, direct imaging, multi-slit spectroscopy, and integral field spectroscopy, the main objective of the instrument is to study the early universe through massive [[redshift survey]]s, such as the [[VIMOS-VLT Deep Survey]].<ref name="eso0804">{{cite web |url=https://www.eso.org/public/unitedkingdom/news/eso0804/ |title=New Light on Dark Energy—Probing the cosmic Web of the Universe |work=ESO |date=30 January 2008 |type=eso0804, Science Release}}</ref>

VIMOS saw its [[First light (astronomy)|first light]] on 26 February 2002, and has since been mounted on the Nasmyth B focus of VLT's ''Melipal'' unit telescope (UT3).<ref>{{cite web |url=https://www.eso.org/public/unitedkingdom/teles-instr/vlt/vlt-instr/vimos/ |title=VIMOS—Visible Multi-Object Spectrograph |work=ESO |access-date=2 August 2015}}</ref><ref name="eso0209">{{cite web |url=https://www.eso.org/public/unitedkingdom/news/eso0209/ |title=VIMOS—a Cosmology Machine for the VLT. Successful Test Observations With Powerful New Instrument at Paranal |work=ESO |date=13 March 2002 |type=eso0209, Science Release}}</ref>

It was retired in 2018 to make space for the return of CRIRES+.<ref name="Paranal – decommissioned instrument">{{cite web |title=Paranal – decommissioned instruments |url=https://www.eso.org/sci/facilities/paranal/decommissioned.html |access-date=21 July 2021}}</ref>
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== Gallery ==

<gallery class="center" mode="packed" heights="150px" style="text-align: left;">
File:Magnificent Spiral Galaxy NGC 7424.jpg|Galaxy [[NGC 7424]] seen by VIMOS
File:NGC 5317 (also NGC 5364).jpg|VIMOS takes its [[First light (astronomy)|first light image]] of galaxy [[NGC 5364]]
File:NGC 6769.jpg|A triplet of galaxies seen by VIMOS
File:Phot-09a-02-normal.jpg|The [[Antennae Galaxies]], one of VIMOS' first images
File:A Pool of Distant Galaxies.jpg|The [[Chandra Deep Field South]]
File:ACO 3341.jpg|VIMOS images the 500 million light years distant [[Galaxy groups and clusters|galaxy cluster]]  ''ACO 3341''
File:Phot-09g-02-hires.jpg|Galaxy ''NGC 2613'', a [[spiral galaxy]] that resembles our own [[Milky Way]]
File:NGC 6118 (captured by ESO’s Very Large Telescope).jpg|VIMOS sees cluster [[NGC 6118]] at a distance of 80 million light-years
File:ESO- SN 2006X in Messier 100-Phot-08b-06.jpg|[[Messier 100]] seen in different filters by VIMOS (left) and [[Very Large Telescope#Instruments|FORS&thinsp;1]]. ''(Note supernova [[SN 2006X]] in the middle of the right image, just above the lower main spiral arm)''.
File:The Hyperion Proto-Supercluster.jpg|Visualization of the [[Hyperion proto-supercluster]] found within [[Cosmic Evolution Survey|COSMOS]] seen by VIMOS.<ref>{{citation|title=Largest Galaxy Proto-Supercluster Found - Astronomers using ESO's Very Large Telescope uncover a cosmic titan lurking in the early Universe|url=https://www.eso.org/public/news/eso1833|publisher=[[European Southern Observatory]] (ESO)|id=Science Release eso1833|date=17 October 2018|access-date=19 October 2018}}</ref>  
</gallery>

<gallery class="center" mode="packed" heights="180px">
File:Vlt-vimos close-up wide screen.jpg|Close-up of VIMOS
</gallery>

== See also ==
* [[List of instruments at the Very Large Telescope]]

== References ==
{{Reflist}}

[[Category:Astronomical instruments]]
[[Category:Telescope instruments]]
[[Category:Spectrographs]]
[[Category:2002 introductions]]
[[Category:2002 establishments in Chile]]