Large Millimeter Telescope

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Large Millimeter Telescope
Organization National Institute of Astrophysics, Optics and Electronics, University of Massachusetts Amherst
Location Volcán Sierra Negra
Coordinates 18°59′09″N 97°18′53″W / 18.98583°N 97.31472°W / 18.98583; -97.31472Coordinates: 18°59′09″N 97°18′53″W / 18.98583°N 97.31472°W / 18.98583; -97.31472[1]
Altitude 4,640 metres (15,200 ft)
Wavelength 0.85–4 mm (75–350 GHz)
Built 2001-2010
First light 2011-06-17[2]
Telescope style Bent Cassegrain
Diameter 50 m
Secondary dia. 2.5 m
Angular resolution 5″ at 1 mm
Collecting area 1960 m²
Focal length 525 m
Mounting Altitude-azimuth
Website http://www.lmtgtm.org/

The Large Millimeter Telescope (LMT) (Spanish: Gran Telescopio Milimétrico, or GTM) was inaugurated in Mexico on 22 November 2006. It is the world's largest single-aperture telescope in its frequency range, built for observing radio waves in the wave lengths from approximately 0.85 to 4 mm. It has an active surface with a diameter of 50 metres and 2000 m² of collecting area.

Location of the LMT.

It is located within Chalchicomula de Sesma municipality, on top of the Sierra Negra, the fifth highest peak in Mexico and an extinct volcanic companion to Mexico's highest mountain, the Pico de Orizaba, in the state of Puebla. Its construction took 10 years, and cost 116 million dollars. It is a binational Mexican (80%) – American (20%) joint project of the Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE) and the University of Massachusetts Amherst.

Millimeter wavelength observations using the LMT will give astronomers a view of regions which are obscured by dust in the interstellar medium, thus increasing our knowledge about star formation. The telescope is also particularly fitted for observing solar system planetesimals and planets and extra-solar protoplanetary disks which are relatively cold and emit most of their radiation at millimeter wavelengths. There are also proposals for observing fluctuations in the cosmic microwave background as well as active galactic nuclei.

Controversy[edit]

High costs[edit]

Through 2012, the total reported investment for the GTM by Mexico had surpassed 1,548.6 million Mexican pesos[3] (around 130 million USD). The telescope, now in its first phase of early scientific operations, has an annual cost of 5.5 million USD per year, which makes it the largest and most expensive scientific venture in Mexico's history. However, this investment is still modest when compared to other major astronomical facilities worldwide.

Delays in finishing the project[edit]

The telescope construction officially lasted six years, from early 2000 until its inauguration by president Fox in November 2006, but actually still goes on. LMT made a token first astronomical observation at 12 GHZ (or 2.5 cm) in 2006 during the inauguration, but its first light in the millimeter band could not be announced until the 1st of June 2011. LMT started a phase of early science operations in May 2013 and has been operating as a 32m telescope since. The current surface makes it already the largest single dish millimeter telescope in the world, though only by little and only in the 4mm to 1.3mm bands. The surface of the telescope is to be completed late in 2015 and will have to be adjusted to usefully operate down to 0.8mm. In 2012 the project was accused of having been "inaugurated" on two occasions, but the visit of president Felipe Calderon Hinojosa in September 2012 was in fact carefully termed a "visit of supervision".

Building Expertise[edit]

The LMT project has had the goal of building expertise at INAOE, which together with UNAM (the largest Mexican university) has the most important astronomical community in Mexico. In 1992 INAOE did not have a solid dedicated group of national nor foreign radio astronomers and has been working in its development since. The involvement from the scientists at INAOE represented over 50% of the proposals received in the August 2014 call for proposals.

The building expertise on the Mexican side is reflected on the Project Scientist on the Mexican side, Chavez-Dagostino, which has been increasing his publications on radio and millimeter astronomy.

Thefts[edit]

In 2012, 128 real panels were stolen from the GTM installations before they were installed. They were recovered by Mexican authorities from the house of one of the thieves after an anonymous tip.[4]

References[edit]

External links[edit]