Year: 2018-19
Sneha Kar
School: St Anthony's High School
Grade: 9
City: Chandannagar, West Bengal
Introduction
Enceladus is a fascinating moon of Saturn. I choose to photograph Enceladus because I think its without doubt a very special moon, with most unusual geographical features and structures and as I appreciate in JPL's videos and simulations, it must have tremendous cliffs and gorges but what catches my attention most is the possibility of having life on it. The scientist have already sent some spacecraft to Enceladus like Voyager 1 and 2 Cassini.
Potential habitability
Enceladus ejects plumes of salt water that are laced with grains of silica rich sand, nitrogen (in ammonia) and organic molecules including trace amount of simple hydrocarbons such as methane (CH4), propane (C3H8), acetylene (C2H2) and formaldehyde (CH2O) which are carbon bearing molecules. This indicates that hydro thermal activity – an energy source may be at work in Enceladus subsurface ocean. In addition models indicating the large rocky core is porous, allowing water to flow through it to pick up heat.
Molecular Hydrogen (H2) , a geochemical source of energy that can be metabolized by methanogen microbes to provide energy for life, could be present if, as models suggest Enceladus salty ocean has an alkaline pH from serpentinization of chondritic rock.
The presence of an internal global salty ocean with an aquatic environment supported by global ocean circulation patterns with an energy source and simple organic compounds in contact with Enceladus rocky core, may advance the study of potential habitable environments for microbial extraterrestrial life.
Several robotic missions have been proposed to further explore Enceladus and assess its habitability. Some of the proposed missions are:
Journey to Enceladus and Titan, Enceladus life finder and Life investigation for Enceladus.
On April 13, 2017, NASA announced the discovery of possible hydrothermal activity on Enceladus sub- surface ocean pole. A mass spectrometer on the Cassini craft detected moleculaur hydrogen particles from the plumes and after months of analysis, the conclusion was made that the hydrogen was most likely the result of hydrothermal activity beneath the surface. It has been speculated that such activity could be a potential oasis of habitability.
The presence of ample hydrogen in Enceladus ocean means that microbes if any exists there- could use it to obtain energy by combining the hydrogen with carbon-di-oxide dissobled in the water. The chemical reaction is known as “methanogenesis” because it produces methaneas a byproduct , and it is the root of the tree of life in earth, the birthplace of all life that is known to exist.
In the future, NASA hopes to send another mission to the system to further explore these plumes and the interior of Enceladus. The mission will likely include a new instrument that was recently announced by NASA known as submillimeter. Enceladus life fundamentals Instrument (SELFI). This instrument, which was proposed by a team from the NASA Goddard Space Flight Centre, recently received support for further development, I hope scientists can find life on Enceladus. That's why I want to photograph Enceladus."
