NASA Scientific and Technical Aerospace Reports

Telescope (HST) at optical wavelengths. More recently, Spitzer Space Telescope made a direct detection of the infrared
radiation from the planet. Aside from the important statistical fact that gas giant planets do exist in more than 7% of nearby
F, G, K and M (main sequence) stars, and more preferably around metal-rich ones, the wealth of radial velocity data has also
unveiled the existence of hot Jupiters -gas giant planets orbiting very close to their parent star in scorching hot regions clearly
not conducive to the formation of Jovian planets (which are made mostly of volatile gas). It is now believed that those worlds
were likely formed at larger distances beyond the so-called snow line, (where water and other volatiles would condense out
of the cloud of gas and dust that form a planetary system) and migrated inward either through disk-planet dynamical
interaction and/or planet-planet gravitational interaction. Clearly, it has been a very busy and exciting first decade for the
still-infant discipline of exoplanetary science. We have yet to probe and search at relatively large (greater than 5-6
astronomical units (AU)) semi-major axes, a parameter-space impractical for the radial velocity technique since it requires
long baseline measurements patiently acquired over a significant fraction of one orbital period. For planets like Jupiter and
Saturn, this time frame corresponds to 12 and 29 years, respectively.
Derived from text
Astronomy; Planetary Systems; Surveys; Gemini Project; Planet Detection
20060000071 Gemini Observatory, Hilo, HI, USA
Recent Science Highlights
Roy, Jean-Rene; Fischer, Scott; Gemini Focus: Newsletter of the Gemini Observatory; December 2005, pp. 49-53; In English;
See also 20060000060; Copyright; Avail.: Other Sources
Over 82 separate nights the Gemini North and Keck I telescopes mapped the clouds 0 of Saturn’s largest moon Titan
during a coordinated monitoring imaging campaign during the moon s 2003-2004 and 2004-2005 apparitions. Henry G. Roe
(CalTech) and a team including Gemini s Chad Trujillo, found that Titan s recently discovered short-lived mid-latitudes clouds
cluster near 350 degrees west longitude and 40 degrees south latitude. They can last as long as one Earth day before
dissipating. The observations point to a localized surface event such as geysering or cryovolcanism as a possible trigger for
the formation of these clouds. The team used adaptive optics systems on both Mauna Kea telescopes to map Titan s surface
and atmospheric features at a spatial resolution of about 300 kilometers as shown in Figure 1 inset images. At Gemini North,
the nightly monitoring of Titan with ALTAIR, (the facility adaptive optics system), was done as a test for multi-instrument
queue observing, a mode that is now fully implemented.
Derived from text
Titan Atmosphere; Dissipation; Infrared Telescopes; Spatial Resolution; Methane
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