NASA–Webb–Keck Observation of Titan

About Titan

• Titan is the largest moon of Saturn and the second-largest moon in the solar system, after Jupiter's Ganymede.
• It is the only known moon with a thick atmosphere and surface liquid bodies, including lakes and seas of methane and ethane.
• Titan exhibits Earth-like weather patterns, including clouds, rainfall, and seasonal variations.

Key Findings

• These observations revealed the presence of clouds in the mid- and high northern latitudes of Titan that rose to higher altitudes over time, indicating convection-driven weather patterns.
• This marks the first-ever confirmed evidence of convective cloud activity in Titan’s northern hemisphere, where most of Titan’s hydrocarbon seas (like Kraken Mare and Ligeia Mare) are located.
• The findings offer fresh insights into Titan's active methane cycle, which is analogous in complexity to Earth’s hydrological cycle, but with methane and ethane instead of water.
• Understanding Titan's weather helps scientists better comprehend prebiotic chemistry and climate dynamics on icy moons with thick atmospheres.

About Keck Observatory

• The M. Keck Observatory is located near the summit of Mauna Kea, a dormant volcano in Hawaii, at an altitude of 4,200 metres. This high elevation provides evident atmospheric conditions for astronomical observations.
• The observatory consists of two 10-metre telescopes, Keck I (operational since 1992) and Keck II (since 1996), making it the largest optical/infrared telescope system in the world.
• Each telescope has a 10-metre primary mirror composed of 36 hexagonal segments made of zero-expansion glass ceramic, which ensures thermal stability and precision imaging.
• These segments are adjusted in real-time by computer-controlled actuators to maintain the mirror's hyperboloid shape, enabling ultra-precise focus and light collection.
• A technique called stressed mirror polishing was used to shape the asymmetric off-axis segments, a breakthrough innovation in modern telescope engineering.