The Gemini Observatory's New Infrared Instrument Is Finally Ready to Stare

After a year long delay, the new FLAMINGOS-2, a powerful infrared camera and spectrograph, is finally turning to the sky at the Gemini South observatory in Chile. FLAMINGOS stands for "FLoridA Multi-object Imaging Near-ir Grism Observational Spectrometer," because it was developed by a team at the University of Florida and presumably because "F-MOINIGOS" sounds ridiculous. In an email, one of the astronomers at the observatory just referred to it as "F2."

Images taken by the FLAMINGOS-2 during its last commissioning phase are already real stunners. The instrument is still being fine-tuned to work with Gemini South’s 8.1 meter diameter telescope, but scientists are confident that they’ve fixed the problem that cracked the large collimator lens during the FLAMINGOS-2’s scheduled final commissioning in February 2012.

The lens in question has a diameter of 26 centimeters and is made of calcium fluoride. It sits in near-vacuum like conditions, along with customizable "multi-object spectroscopy masks," which allow the lens to look at several things at once, but the operating temperature for this part of the telescope is 100 degrees Kelvin, or almost 280 degrees below zero Fahrenheit.

"The instrument works in the near-IR. At the reddest part of the near-IR (2 microns of wavelength) the emission from objects at room temperature is brighter than the sky," said Percy Gomez, Gemini’s FLAMINGOS-2 Instrument Scientist, in an email. "Therefore, we would have a hard time detecting very faint objects. So the instrument is kept at very low temperature."

To switch out the masks, the apparatus had to be warmed up to room temperature, then cooled back down to be used. "We believe that it was during one of these thermal cycles that the lens cracked," said Gomez.

“It has not been an easy journey,” said Gomez, “but thanks to the dedicated work of Gemini engineers and scientists very soon astronomers will be able to use a reliable and robust instrument.” The cracked lens has been replaced and the lens holder was redesigned to exert less pressure on the lens while it is in operation, and the FLAMINGOS-2 is ready to produce more pictures like this one:

The instrument is attuned to pick up infrared (heat) radiation from the universe, as opposed to reflecting telescopes that amplify visible light. Infrared photons are readily absorbed by water vapor, so the summit of Cerro Pachon in Chile in the dry Andes air is an ideal place for FLAMINGOS to perch, and another reason to keep the lens so chilly.