Telescopio Nazionale Galileo

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Telescopio Nazionale Galileo
View of the telescope housing from outside, with GranTeCan under construction in the background.
Organization	Italian National Institute of Astrophysics (INAF)
Location	Roque de los Muchachos Observatory, La Palma (Canary Islands)
Wavelength	optical, near-infrared
Built	1998 (first light)
Telescope style	reflector
Diameter	3.58m
Collecting area	~12m²
Mounting	altazimuthal
Dome	up and over
Website	http://www.tng.iac.es/

The Telescopio Nazionale Galileo, or TNG, is a 3.58m telescope located on the island of San Miguel de La Palma (or, more simply, La Palma), in the Canary Islands archipelago. It is one of the largest telescopes hosted by the Roque de los Muchachos Observatory, one of the most important observing sites in the northern emisphere. It is now operated by the "Fundación Galileo Galilei, Fundación Canaria", a no-profit institution which manages the telescope on behalf of INAF, the Italian National Institute of Astrophysics. The telescope saw its first light in 1998.

Observations at the TNG can be proposed through the Italian Time Allocation Committee (TAC) which assigns, based on the scientific merit of the proposals, 75% of the available time. The rest of the time is at disposal of the Spanish and international astronomical communities. The TNG is open to new proposals two times a year, typically in March-April and September-October.

1 Technical characteristics
2 TNG public data archive
3 See also
4 External links

[edit] Technical characteristics

The TNG is an altazimuthal reflecting telescope with a Ritchey-Chretien optical configuration and a flat tertiary mirror feeding two opposite Nasmyth foci. It has a design derived from the New Technology Telescope (NTT), an ESO 4-meters class telescope located in La Silla (Chile). Therefore, the optical quality of the telescope is ensured by an active optics system performing real-time corrections of the optical components and compensating, in particular, for the deformations of the primary mirror, which is too thin to be completely rigid. Nevertheless, unlike the NTT, the TNG is also equipped with an adaptive optics system providing diffraction limited images in the near-infrared band.

The interface between the telescope fork and the instruments at both Nasmyth foci is provided by two rotator/adapters. Their main function is to compensate for the field rotation by a mechanical counter rotation. The best quality of the TNG is that all the available instruments are permanently mounted at the telescope. The first focal station, Nasmyth A, supports the direct imaging camera (OIG), the near-infrared camera-spectrometer (NICS) and the Adaptive Optics module (AdOpt@TNG). The second focal station, Nasmyth B, supports the optical multimode instrument (DOLoRes) and the high resolution spectrograph (SARG).

The science based on observational data from the TNG is varied. Proposed observing programs go from the study of the planets and minor bodies of the solar system up to researches of cosmological interest (e.g. large-scale structure of the Universe and systems of galaxies).

[edit] TNG public data archive

The IA2 (The Italian Astronomical Archive Center) has implemented the TNG Long-Term Archive (LTA). It makes possible the use of the TNG public data, searching and downloading them from the web portal: TNG Archive.