Cassini Spacecraft

In News

• NASA’s Cassini spacecraft has detected an unusually high concentration of methane, along with carbon dioxide and dihydrogen, in the moons of Saturn by flying through their plumes.

Moons of Saturn

• Saturn has 82 moons with confirmed orbits that are not embedded in its rings.
• Particularly notable among Saturn's moons are:

1. Titan, the second-largest moon in the Solar System (after Jupiter's Ganymede), with a nitrogen-rich Earth-like atmosphere and a landscape featuring dry river networks and hydrocarbon lakes,
2. Enceladus, which emits jets of gas and dust from its south-polar region, and

• Lapetus, with its contrasting black and white hemispheres.

Findings by Cassini

• The spacecraft has found that Titan has methane in its atmosphere and Enceladus has a liquid ocean with erupting plumes of gas and water.

Processes of Methane Formation

• Methane could be formed by the chemical breakdown of organic matter present in Enceladus’ core.
• Hydrothermal processes could help the formation of carbon dioxide and methane.
• On Earth, hydrothermal vents on seafloors are known to release methane, but this happens at a very slow rate.
• Possibility of Micro organisms called Methanogens.

Note: Searching for such microbes at Enceladus’ seafloor would require extremely challenging deep-dive missions that are not in sight for several decades.

Cassini

• Cassini, is a collaboration among NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its rings and natural satellites.
• The Flagship-class robotic spacecraft comprised both NASA's Cassini space probe and ESA's Huygens lander, which landed on Saturn's largest moon, Titan in 1997.
• Cassini was the fourth space probe to visit Saturn and the first to enter its orbit.

https://indianexpress.com/article/explained/plumes-on-enceladus-possibility-of-life-on-saturns-moon-explained-7395434/