very large telescope.
A Telescope is an optical device for welting light in order to form the images of the distinct objects. Very Large Telescope (VLT) is a telescope which is operated by the southern Observatory or Cevro Parnell in the Ataman Desert of Southern Chile VIT consists of four individual telescopes each with the primary mirror 8,2m diameter which are generally used separately but can be used together to achieve very high resolution The four telescopes are Unit Telescopes (UTs) which are also known as Antu (UTi, the sun), Kueyn (UTii, the moon), Melipal (UTii, Southern Cross), and Yepun sirius word ‘Venus’) U Tiv, Venus as the evening star. These are all the words for astronomical objects in Mapuche Language. The telescope for an array which is complemented by four moveable Auxiliary Telescopes (ATs) of 1.8m apertum. The VLT operates at visible and infrared wave lengths Each indivisible telescope can detect objects roughly four billion times fainter than what can be detected by the naked eye, and when all the telescopes are combined, the facility can achieve an angular resolution about 0.001 arc seconds. The VLT is the most productive ground- based facility for astronomy with only Hubble telescope generating more scientific papers among facilities operations at visible wavelength. Among the pioneering observation carried out by using VLT are the first direct image of an exo-planet, the tracing of individual stars moving around the super massive black holes at the carter of Milky Way galaxy and observation of the afterglow of the further known gamma ray burst A laser is also used for adaptive optics (excites sodium atoms in atmosphere and creates artificial stars) The VLT consists of an arrangement of 408.2m diameter) telescopes (UTI,UT2 UT3, & UT4) with optical element which can combine into an astronomical nferometer WLTI which is used to revolve the small objects. This technique using inferometer is called inferomatory (combining light from multiple telescopes) The inferometer also includes a set of four 18 meter diameter moveable telescopes dedicated to interferometer observation The first UTs started operating in May 1998 and was offered co asaouomcai community on 1″ April 199g The other telescope followed Suit in 199g and 2000, thus making VLT fully operational Four 18 meter Auxiliary Telescopes have been added to VLTI to make it available when the UTs are being used for other project These ATs were installed between 200 to 2007 Today all four Unit Telescopes are operational Unit Telescopes The UTs are cquipped with a large set of instruments permitting observation to be performed from near ultra violet to mid infrared (i e a large fraction of light wavelength accessible from the surface of earth) with full range of the technique including high resolution spectroscopy, multi object spectroscopy maging, and high resolution imaging In particular, the VLT has several adaptive optic systems which cover the effect of atmospheric turbulence and providing images almost as sharp as if the telescope was in space. The 8.2m diameter telescopes are housed as compact, thermally controlled buildings which rotate synchronously with the telescope. This design mini-mizes any adverse effect on the observing condition, for instance from air turbulence in the telescope tube which might, otherwise, occur due to variation in temperature and wind flow. Auxiliary Telescope: Although, four 8.2m diameter UTs can be combined in VLTI, they are mostly used for individual observations and are only available to inferometer observations for limited number of night every year. But, four smaller 1.8 meter ATs are available and dedicated to inferometery to allow V.L.TI to operate every night. The top part of each A. T is a round enclosure made from two sets of three segments which open and close; its job is to dedicate 1.8m telescope from the desert conditions. The enclosure is supported by the boxy transporter section which also contains electronic cabinets, liquid cooling systems, air conditioning units, power supplies, and more. During astronomical observations, the enclosure and the transporter are mechanically isolated from the telescope into ensure that no vibrations compromise the data collected. The transporter section runs on tracks. So, AT s can be moved to thirty different observing locations. As the VLT acts rather like a single telescope as large as the group of telescopes combined, and changing the position of ATs, it means that VLTI can be adjusted according to the need of the observing project.