Dr Anjani Ganase reflects on the ocean as a source of life; and the possibility that where there is water in the universe, there might be life.
Breathe in and out, look around, see life all around us. Life as we know it is the culmination of evolution that started over three billion years ago on this planet in our ocean. We have evolved enough to be able to trace our origins but also to seek out other origin stories in our solar system and beyond. Life requires the presence of energy, organic molecules to be organised and structures and water as the medium for chemical reactions and transport of elements and nutrients.
Our planet is home to a large body of waters, the ocean occupies 70 per cent of planet earth. It is the keeper of climates and maintains life. Our planet received deposits of frozen water from space over billions of years from comets and asteroids colliding with the surface of the planet. As the planet warmed, the water collected to form the ocean. While water is common on other planets, as it resulted from the formation of the universe during the Big Bang, it is very common as water vapour or frozen as ice.
[caption id="attachment_1155160" align="alignnone" width="1024"] Jezero crater on Mars, the landing site for NASA's Mars 2020 mission. On ancient Mars, water carved channels and transported sediments to form fans and deltas within lake basins. Photo courtesy NASA/JPL-Caltech/MSSS/JHU-APL -[/caption]
Liquid water is rarer, so when seeking life, we must go where the water flows. We observe the water vapour through the Hubble telescope around stars and nebulas (space dust found where new stars are born). We also observed frozen ice on many planets and moons in our solar systems.
Scientists have been looking for liquid water throughout our solar system and even beyond it. Just looking at our neighbours, Mars’ atmosphere is thinner than earth. Evidence of liquid water is seen on the surface of Mars where water has eroded the surface with the formation of rivers and lakes leaving behind scars. Scientists speculate that the patterns came from an era where water existed in plenty but the thinning atmosphere likely resulted in the transport of water out of the atmosphere into space. What’s left are frozen ice caps giving some potential for microbial life. Our other neighbour, Venus was also suspected of housing an ocean, but similar to Mars, the thin atmosphere and a run-away planet climate (warming conditions) would have boiled the water out of the atmosphere.
Looking farther away in our solar system, scientists have sought out places where water exists with the hope that there may be flowing water and signs of life. Using sophisticated telescope technologies such as the James Webb Space Telescope or the Kepler telescope capable of detecting the full electro-magnetic spectrum from infrared, visible light to ultraviolet and gamma rays to discern the chemical compositions of planets faraway. Frozen water can be found on several moons around Jupiter and Saturn. Moons of Jupiter – Europa and Ga
