CNoisette

South African Astronomical Observatory

http://www.uiuc.edu

South African Astronomical Observatory

An image of the Great Comet through a telescope.
Location	Headquarters in Observatory, Cape Town; telescopes in Sutherland, Cape Town

South African Astronomical Observatory (SAAO)

South African Astronomical Observatory is the national center for optical infrared astronomy in South Africa. It was established in 1972. The observatory is run by South Africa's National Research Foundation. The facility's function is to conduct research in astronomy and astrophysics. The primary telescopes are located in Sutherland, which is a four hour drive from Observatory, Cape Town, which is where the headquarters is located. The SAAO has international links worldwide that exchange scientific and technological collaboration. Contributions from the South African Astronomical Observatory to the science field include the development of a spherical aberration corrector and the Southern African Large Telescope, otherwise known as SALT, which was inaugurated in November 2005. Much research as been done with the telescope including investigation of black holes and polar stars.

History

The SAAO started when the Royal Observatory at the Cape of Good Hope was founded in 1820, the first scientific institution in Sub-Saharan Africa. During the 1970’s, the Republic Observatory in Johannesburg and the Radcliffe Observatory in Pretoria merged with the much older Royal Observatory to form the South African Astronomical Observatory.

SAAO was established in January 1972 as a result of a joint agreement by the Council for Scientific and Industrial Research (CSIR) of South Africa and Scientific and Engineering Research Council (SERC) of United Kingdom. The headquarters are located on the grounds of the old Royal Observatory where the main building, offices, national library for astronomy and computer facilities are housed. Historic telescopes are also found at the headquarters in a number of domes and a small museum that displays scientific instruments. The South African Astronomical Observatory is administered as a National Facility under management of the National Research Foundation (NRF), now formerly Foundation for Research Development (FRD). In 1974, when the Radcliffe Observatory in Pretoria closed, the Royal Observatory and the Republic Observatory combined facilities. The Council for Scientific and Industrial Research (CSIR) purchased the 1.9 Radcliffe telescope and transported it to Sutherland.

SALT

The South African Astronomical observatory (SAAO) is home to the world-wide known telescope SALT. SALT is an acronym for Southern African Large Telescope. SALT was inaugurated in November 2005. It is the largest single optical telescope in the Southern Hemisphere, with a hexagonal mirror array 11 meters across. SALT shares similarities with the Hobby-Eberly Telescope (HET) in Texas; however, SALT used more mirror array. The Southern African Large Telescope gathers twenty-five times as much light as any existing African Telescope. With this larger mirror array, SALT can record distant stars, galaxies and quasars.

The Southern African Large Telescope is partnered with many countries globally involved with astronomical research. Partners include: National Research Foundation (RSA), Nicolaus Copernicus Astronomical Center from Poland, Inter-University Centre for Astronomy and Astrophysics from India, Georg-August-Universität Göttingen from Germany, University of Canterbury from New Zealand, the internationally-known Hobby-Eberly Telescope Board, Consortium of UK Universities and Institutions, and a number of United States institutions such as Rutgers University, University of Wisconsin - Madison, Carnegie Mellon University, University of North Carolina - Chapel Hill, Dartmouth College, and the American Museum of Natural History.

SALT is a computer-run precise device that connects researchers around the globe through the Internet. Astronomers can access SALT through their computers, by submitting observing requests. Once the observations have been conducted, the data is sent via Internet. It has been said that the Southern African Large Telescope is more space-based similar to CHANDRA and the Hubble Space Telescope. SALT is a ~10 meters (~33 feet) diameter optical telescope, located in the semi-desert region of the Karoo, South Africa.

Research

Many years of research using SALT at the South African Astronomical Observatory has led the facility to important discoveries. By using the Southern African Large Telescope, SAAO has the ability to take “snapshots” of starts in very quick succession. It is optimized for wavelengths and observing modes not available on other very large telescopes. As a result, astronomers can study rapidly changing properties of compact stars, primarily as they pull in gas from their companion stars or surroundings. The significance of this discovery allows us to detect black holes.The gravitational field of a compact star commonly pulls in gas from a companion star, thus radiation (especially X-ray) is emitted. Scientists used this as an indirect way to locate black holes. Another phenomenon that SALT has helped astronomers investigate is the way that masses build up on some compact stars until supernova explosions blow them apart, which gives scientists a "Type 1a" supernovae used to show that the expansion of the universe is speeding up.

Other note-worthy research the South African Astronomical Observatory has achieved using SALT include the discovery of a class of stars known as "polar", or a pair of stars. The "polar" binary star system, where a compactor star called a "white dwarf" whose volume has shrunk about one millionth of a star like our sun. Studies using SALT concluded that these polar binary start systems take only an hour and a half to complete an orbit. Also, the SALT telescope allows scientists to study the rapid brightness changes in exotic stars.

More research using SALT has aided astronomers investigate the structure and evolution of our galaxy, such as quasars, Magellanic clouds, the galactic structure and stellar astrophysics. SALT released its first color images, which marked the achievement of the "first light". This also marked the debut of the fully operating SALTICAM, which is a $600,000 digital camera designed and built for SALT. First light with the full mirror was declared on 1 September 2005 with 1 arc second resolution images of globular cluster 47 Tucanae, open cluster NGC 6152, spiral galaxy NGC 6744, and the Lagoon Nebula being obtained.

Facilities

Telescopes

• SALT
• 1.9 m (Radcliffe) Telescope and Instrumentation
• 1.0 m (Elizabeth) Telescope
• .75-m Telescope
• .5 m Telescope
• ACT: Alan Cousins Telescope
• BiSON
• IRSF
• MONET
• YSTAR

Geophysical

• SAGOS
• SUR

References

• http://www.saao.ac.za/
• http://www.nrf.ac.za/facilities/saao/
• http://www.salt.ac.za/public-info/milestones/first-light/
• http://www.salt.ac.za/public-info/milestones/inauguration/press-release/
• http://flickr.com/photos/pix_elate/2609507073/