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How Good Is Your Science KQ?
[i.e. your Knowledge Quotient]
Cassini-Huygens and Saturn's Titan
Looking up at the sky on a clear night one sees an amazing and uncountable number of twinkling ‘stars.’ These bright points of light have been
studied for thousands of years with the naked eye, and for hundreds of years
with telescopes, by people with their feet firmly planted on the ground. Their
observations have been transformed into fascinating diagrams, drawings,
paintings and light-camera photographs. This is all changing now as different
technologies and techniques are emerging and being used in astronomical
investigations.
A current investigation being carried out by the National Aeronautic and Space Administration (NASA), the European Space Agency (ESA), and the Italian Space Agency (ISA) has a spacecraft that has been traveling for more than 6 years through space in order to reach the vicinity of the planet Saturn at the end of 2004.
[Below: Artist's drawing of the Huygens probe in the vicinity of Titan (NASA)]
Launched from Cape Canaveral in the US on October 15, 1997, the 5.6-ton
Cassini spacecraft is bound for Titan, the second largest of Saturn’s 31
moons. Cassini will orbit Saturn three times and then send its probe (named
Huygens) on a 22-day cruise timed to descend by parachute to the surface of
Titan on January 14, 2005. Both spacecraft will carry out precise physical observations and the resulting data will be transmitted by Cassini to NASA computers on Earth.
As this stumper is being written Cassini has already transmitted some information about Titan's surface to the scientists at NASA.
The Huygens probe will use techniques that do not rely on
the naked eye, telescopes or even visible light. Advances in scientific
understanding and technologies, allow observations now to be based on
information derived from other types of electromagnetic radiation such as
infrared, X-rays, and radar.
Astronomers have already determined that Titan
has a thick, murky, orange-colored atmosphere that is mostly nitrogen, with
methane and other organic compounds and, in 1998, ESA’s Infrared Space
Observatory detected the presence of water vapor in the atmosphere.
Huygens is carrying instrumentation to analyze samples of the atmosphere collected as it
lands, measure the physical and electrical properties of the atmosphere,
determine the direction and strength of Titan's zonal winds, and provide
information on the composition of the surface material. We do not yet know if
Huygens will land on a rocky, icy surface or splash into a sea of ethane or
methane but if all goes well we will have such information by early Spring
2005.
The Stumper Questions:
- Which astronomer
discovered Titan: Christiaan Huygens (1629-1695), or Jean-Dominique Cassini
(1625-1712)
- Infrared radiation and X-rays are used in medical studies on Earth. Can you
identify at least two examples of such use for each?
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