Persevering with our Martian fantasies Unresolved questions and the hope of finding life on the planet have intrigued experts for decades

er will roam around this crater and sample carbonate rocks that might host algal mats called stromatolites, as we find in the oldest carbonate rocks on Earth.

C.P. Rajendran Still a mystery But as a geologist, I will remain scep- tical until I see some hard evidence The recent NASA mission of putting on biogenic remains. My concern is its latest rover, Perseverance, on not about the existence of the origi- Mars — a breathtaking technological nal conducive conditions for the mi- feat — has once again ignited our Mar- crobial forms of life to thrive, some tian fantasies and the fascination four billion years ago. It may have with discovering alien life forms. In- New horizons: A section of a composite image taken by the Perseverance rover been a reality. My concern would be grained in our minds is the idea that shows the rim of the Jezero crater. * AP the complex factors that control the Mars holds some sort of wherewithal preservation potential of organic in the innumerable crannies within After painstaking telescopic work dence of clays that may have formed matter and other biosignatures in the its rocks to support traces of life. The that was set up on the desert of Ari- after solid rocks were exposed to wa- four-billion to 3.5-billion-year-old question that whether humans will zona, Lowell, after years of observa- ter, as analogous examples of Earth’s phyllosilicate-rich terrain of Mars, be able to make use of even such tion, talked about hundreds of canals rock inventory would testify. But which shows evidence of sustained modicum of habitability to utilise its on the equatorial region of Mars. He some scientists were not easily con- weathering of sediments with liquid landscape is also significant, assum- propagated the idea that these were vinced as their Martian climate mo- water. Like the rusty red and iron ox- ing that we will be able to deal with engineered structures used for chan- dels failed to predict temperatures ide-rich lateritic soil we see in the the moral question of whether to cor- nelising water from the polar regions high enough for continuous genera- tropical regions of Earth, the weath- don off the planet from human inter- to meet the requirements of a dehy- tion of rain to have liquid water on ered soil formation of Mars may be a ference in case we do find indigenous drating planet, somewhat eerily re- the surface. So, it was concluded that poor medium to preserve biogenic life forms there. miniscent of a bleak hothouse Earth, any water on Mars would have been signatures. That could be one reason Noted cosmologist Carl Sagan in triggered by the runaway green- locked up in its polar regions with why the Perseverance rover is pro- his 1980 television series Cosmos tit- house effect. brief periods of melting and flooding grammed to seek carbonate rocks led an episode on Mars as “Blues for that carve out the valley networks. within the Jezero crater, where the a Red Planet”. As with Earth, blue is A backup planet? Though Martian climate may not pristine nature of the original biolog- the colour radiated by water, and Historically, Mars has always been have been stable, a corollary expla- ical and climatic signals is expected Earth, therefore, presents itself as a depicted as a backup site for human- nation holds the promise of life in the to be preserved better. We still do not ‘pale blue dot’ to orbiters and astro- ity to migrate to; it is now once again underground niches, where stabler understand the mechanisms of the nauts from outer space. Sagan, pas- being promoted as such by avant- conditions could have prevailed. formation of carbonates on Mars and sionate about Mars, saw its evolution garde entrepreneurs like Jeff Bezos Such examples of subsurface life are whether they are comparable to as a subversion of Earth, one that and Elon Musk. When Sagan was plenty in Earth’s environment. Earth’s processes, which are often started with equally grand designs making his television series, the So- The predecessor of Perseverance, related to oceanic settings. but failed quickly to live up to those viets were trying to explore Mars the Curiosity rover, which has been If the search for evidence of life on early expectations. By naming the with their orbiters. Some successful surveying and testing the Martian Mars is successful, it will prove that episode on Mars as “Blues for a red missions, however, relayed disap- surface since 2012, added some inter- life is a ubiquitous feature of the un- planet”, he probably wanted to high- pointingly bone-dry frames of the esting findings. Most importantly, it iverse, and that will have momentous light his earthly longing for the sea planet. But high-resolution cameras detected carbon-containing com- repercussions on how we see our- and the sky that were thought to be of American-sponsored orbiting mis- pounds in Martian rocks and shifting selves in the overall scheme of distinctive early markers of habitabil- sions launched much later showed levels of methane molecules in the things. But it is also equally possible ity. Thus, singing the blues for a networks of channels most likely to planet’s atmosphere. Two papers pu- that Mars continues to remain a mys- dried-up red planet, Sagan, who was have been sculpted by running wa- blished in the journal Science in 2018 tery if the results turn out to be un- brought up on science fantasies by ter. Thus, modern research informs concluded that these findings sup- certain on the question of microbial Edgar Rice Burroughs and H.G. Wells us that Schiaparelli and Lowell were port the possibility of the existence life — as Casey Dreier of Planetary So- about Martian invaders of Earth, may not completely off the mark in their of microbial life. Inge Loes ten Kate, ciety, an advocacy group of plane- have wanted to signal a lasting tri- interpretations, though Lowell was an astrobiologist at the Utrecht Un- tary exploration, said, “Mars excels bute to a possible glorious Martian wrong in attributing those morpho- iversity, in a commentary on the pap- at denying us our most fervent wish- life of the past. logical features as being engineered ers, said “the question of whether es. From not fitting into the epicycles The Martian science fantasy of the by intelligent beings. A few weeks be- life might have originated or existed of Ptolemy, to lacking the canals of 19th century was an offshoot of re- fore his death, Sagan recorded a on Mars is a lot more opportune now Lowell, to supplying no organic ma- ports of canals on Mars. Nineteenth- moving message for future explor- that we know that organic molecules terial (yet) to the Curiosity rover century Italian astronomer Giovanni ers: “Maybe we’re on Mars because were present on its surface.” team, the reality of Mars has consis- Schiaparelli had claimed that he saw of the magnificent science that can Perseverance, with its companion, tently irritated humanity throughout water-filled canali, or channels, on be done there — the gates of the won- the Ingenuity drone, is the most history.” the red planet. This topic assumed der world are opening in our time...” complex rover ever sent to Mars. It greater significance when a business- More surprises, as well as disap- has now reached its destination, the The author is an adjunct professor at the man-turned-astronomer, Percival Lo- pointments, were in store. In 2005, 45-km-wide Jezero Crater, where an National Institute of Advanced Studies, well, reported similar observations. the Mars Express satellite found evi- old lake supposedly existed. The rov- Bengaluru