Telescope to be set atop Chile mountain

Seeking a higher, drier spot for astronomers to better observe the distant universe, University of Tokyo researchers will shortly install an infrared telescope in the thin air atop a 5,640-meter mountain in the Chilean Andes.

The 1-meter telescope on Mount Chajnantor in the Atacama Desert of northern Chile will stand on a higher elevation than any other when it is completed in late March.

The large reflecting telescope is the first of three to be placed on the mountaintop under the Tokyo Atacama Observatory (TAO) project at the University of Tokyo's Institute of Astronomy in six to seven years.

The project aims to take advantage of the desert aridity and the peak's thin air, which registers pressure of 0.5 atmosphere (about 500 hPa). At lower heights, infrared rays are apt to be absorbed by vapor and air as they travel through the atmosphere.

The Chajnantor summit is optimal for observing infrared light with long wavelengths of around 0.02 to 0.03 millimeter, thus allowing researchers to observe extremely distant galaxies and the births of planets, they said.

Infrared rays at those wavelengths are not observable at lower altitudes.

The 1-meter telescope, with its dome of 6 meters in diameter, will arrive by sea in Chile on Saturday. Its construction and related costs will total around 1 billion yen.

Under the TAO project, a 2-meter Magnum (multicolor active galactic nuclei monitoring) telescope, which the university has operated in Hawaii, will be repaired and also transported up the Chajnantor peak.

A third telescope, with a 6.5-meter diameter to be built at a cost of about 7 billion yen, will join the first two in six to seven years, according to the researchers.

The university team is led by professor Yuzuru Yoshii. The Chilean government has granted the team use of land at the peak for free.

The team also built a 6-kilometer access road that zigzags up to the top.

Telescopes at such heights can be a viable alternative to observation via astronomy satellites, which require much greater costs. Another factor is the difficulty of equipping them with large telescopes.(IHT/Asahi: January 8,2009)