Explained: What plumes on Enceladus tell us about possibility of life on Saturn’s Moon

Source: Indian Express

What is the News?

NASA’s Cassini spacecraft has detected an unusually high concentration of methane along with carbon dioxide and dihydrogen in the moons of Saturn.

What did the Cassini spacecraft find? The spacecraft has found that:

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

Based on this, the researchers have concluded that there may be unknown methane-producing processes on Enceladus that await discovery.

Are there any Methane producing organisms on Earth?

• Most of the methane on Earth has a biological origin. Microorganisms called methanogens are capable of generating methane as a metabolic byproduct.
• They do not require oxygen to live and are widely distributed in nature. They are found in swamps, dead organic matter, and even in the human gut.
• Also, they are known to survive in high temperatures, and simulation studies have shown that they can live in Martian conditions.
• Methanogens have been widely studied to understand if they can be a contributor to global warming.

Possible Reasons for Methane on Enceladus:

• A large amount of methane found on Enceladus is likely coming from activity at hydrothermal vents present on Enceladus’s interior seafloor.
• These vents could be very similar to those found in Earth’s oceans, where microorganisms live, feed on the energy from the vents, and produce methane in a process called methanogenesis.

About Cassini Mission:

• The Cassini-Huygens mission is a collaboration between NASA, ESA (European Space Agency), and the Italian Space Agency.
• The mission was launched in 1997. The spacecraft arrived in the Saturn system in 2004 and ended its mission in 2017.
• Significance: Cassini-Huygens was a mission of firsts. First to orbit Saturn. First landing in the outer solar system. Also, first to sample an extraterrestrial ocean.

About Titan:

• Titan is the largest moon of Saturn and the second-largest natural satellite in the Solar System.
• It is the only moon known to have a dense atmosphere and the only known body in space, other than Earth, where clear evidence of stable bodies of surface liquid has been found.

About Enceladus:

• Enceladus is the sixth-largest moon of Saturn. It is about a tenth of that of Saturn’s largest moon, Titan.
• Enceladus is an active moon that hides a global ocean of liquid salty water beneath its crust.