Last night I attended a public lecture by Prof. Eric Wilcots from University of Wisconsin-Madison, USA held at the Johannesburg Planetarium. The lecture was titled “Seasoning the Universe with a little bit of SALT” in which he spoke about the new Southern African Large Telescope located in the Karoo near Sutherland. The telescope cost R225.36 million ($36 million) to build and has a mirror array of 11 meters in diameter (composed of 91 smaller hexagon segments) making it one of the largest optical telescopes in the world.

According to the professor, one of the biggest reasons for building such a large telescope in the Southern Hemisphere is obviously to observe heavenly bodies (cosmically speaking) that are only visible on this side of the planet. Another feature of these parts of the globe, nicely demonstrated by the planetarium, is that the Milky Way is a lot brighter and clearer in the night sky- So much so that one can observe many individual stars and clusters in the Milky Way. The reason for this is that the Northern Hemisphere is looking outward of our galaxy while the Southern Hemisphere is looking inward where stars are closer and more condensed. Other objects of interest in galactic astronomy exclusive to the southern sky are the Large and Small Magellanic Clouds. These clouds can be seen with the naked eye and are actually dwarf galaxies that orbit our own. Among other things, SALT will allow astronomers to more clearly observe individual stars from these galaxies some 160 000 and 200 000 light-years away. [Hypothetically speaking, if someone were to observe the Milky Way galaxy from a planet in one of these galaxies it must be a spectacular sight- Our galaxy is over 14 times brighter than the LMC appears to us on Earth and would span a width of over 70 full moons across the sky!]

SALT also comes equipped with a spectrometer which can be used to do spectroscopic analysis and identify different chemical elements in celestial bodies and perhaps where they come from. It will also be used to measure Doppler shift, the apparent change in frequency of a wave that is perceived by an observer moving relative to the source of the waves, that will measure if and how fast these bodies move to or away from us.

Apparently SALT collects 10 Gigabytes of data a night, which is a huge amount of information for astronomers to comb through trying to find evidence of origin or cosmic events. In fact, it is not only SALT that needs to manage huge amounts of data but other big observatories have this problem too. Of course one requires powerful computers to process and analyse the data and give astronomers useful summaries or views of what they are looking for. As technology advances and our observatories become more powerful because astronomers are measuring things at higher resolution of detail, the amount of data that will be collected might increase to unmanageable proportions. The professor told me that they hope Moore’s law will allow them to see more of the universe, but also help astronomers to have increasingly powerful computers to process all of that information. A project called SETI@Home uses the Internet to link over 5.2 million volunteer computers using their idle processor time to function as one big super computer that analyse data recorded by the Arecibo Observatory in Puerto Rico.

Consuming a colossal amount of information alone is not the best way to discover the secrets of the Universe, working smarter not harder to make information more useful may give us the answers we seek more efficiently. It makes sense that NASA has partnered with Google, famous for their innovative search technologies, in which the collaborated work will include large-scale data management and massive distributed computing. One of the things that set us apart from computers is our ability to recognize patterns between seemingly unrelated things and use this knowledge to build and discover new phenomena, but we are mostly limited by the speed of our senses and how fast our brain processes information. Artificial Intelligence will still need to make great strides before being of any use, but I believe it will be a great asset in sifting through mountains of soil for those gold nuggets of information.

See also:
Southern African Large Telescope official website
Prof. Eric M. Wilcots University homepage
Wits Planetarium
Large Magellanic Cloud
Small Magellanic Cloud
Doppler Effect
Moore’s law
SETI@home project website
NASA, Google To Collaborate on Technology Research, Development

This entry was posted on Wednesday, March 29th, 2006 at 11:41 pm and is filed under Space. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.