Sutherland, Northern Cape Province, South Africa. Surprisingly, there are three roads that lead to it. One 160 km dirt road from Calvinia, the R354 which is the worst South African road on which we have ever, ever driven; the same dirt road that leads from Sutherland to Fraserburg for another 108 km of sheer torture; and one asphalt paved road, the R354, where you just might run into, literally and figuratively, part of a flatbed tandem lorrie that was unable to ascend the last incline to the top of the last hill before the more-or-less plain. Sutherland, the coldest temperatures in the winter and the hottest temperatures in the summer. Why here? SALT, is the reason.
SALT is the Southern African Large Telescope, located about 15 km off the only part of the paved R354 heading towards Fraserburg, in the South African Astronomical Observatory (SAAO). Here you’ll find a high-powered research astronomical center with an array of telescopes constructed by a consortium of international partners including the United States, Germany, Poland, India, the United Kingdom, and New Zealand. The main telescope, constructed between 2006 to 2009, is considered to be Africa’s Giant Eye on the Universe. It is housed in the building shown on the left, and can be “booked” for professional use either on site or remotely. The SALT for scientists website provides details for international users.
Although similar to the Hobby-Eberly Telescope located at the McDonald Observatory, University of Texas, SALT has a redesigned optical system for its 11 m (33.33 ft) diameter hexagonal mirror array. This redesign results in a larger field of view and effective collecting area, making the SALT telescope is unique. You can see each part of the hexagonal mirror in the image on the right. The primary mirror is spherical in shape, and has an effective aperture of 11.1 m x 9.8 m. Positioned above the mirror is a tracker that moves across it on a virtual spherical focus surface, allowing sky-objects to be “followed” as the earth rotates, without adjusting the azimuth angle for a period of up to two hours. Impressive.
A staff of astrophysicists, astronomers, and technicians live onsite, with accommodations for visiting scientists from around the world. Instruments are controlled from below and include the SALTICAM, which is a highly fast and sensitive CCD imaging camera. This instrument can be operated in a “video” mode, allowing high time resolution (down to ~0.1s) photometry, and also serves as the telscope’s acquisition camera. The telescope also is optimized as an imaging spectrometer (RSS), operating in the UV-Visible region (310 – 900 nm) of the electromagnetic spectrum.
The facility provides the public with a few views of space made with these instruments. One is the “Picture of the Month” which, unfortunately, was last updated in 2011! Another feature for the public is the image gallery; this page was last updated in 2009. And, SAAO offers “first light” images, last updated in 2005. But, I guess that when you’re looking at objects that are light years away and observing processes that occurred millions of years ago, what are regular updates anyway?