By Guido Lanfranchi.
Is there life beyond Earth? And if there is, how can we discover it? On which planet or moon could it be? While we often consider such questions as the topic of science fiction movies and books, scientists at NASA are actually busy in finding concrete answers. On June 19th, Dr. James Green, recently appointed Chief Scientist at NASA, shared his insights about NASA’s efforts in searching forms of life in the solar system.
Making reasonable hypotheses on where to find forms of life beyond our planet, sending space probes across the solar system to collect information, gathering and elaborating such information to refine the hypotheses. These are the tasks that several NASA scientists have been doing, day after day, over the past 15 years, thus dramatically advancing human knowledge on the immense universe that surrounds our planet.
Dr. Jim Green, Chief Scientist of NASA, shared with the international press the efforts of NASA in searching for life beyond our planet. These efforts – Dr. Green said – started to take a more definite shape when NASA asked to several astrobiologists to come up with a definition of life. The experts formulated a definition that could not really satisfy space scientists, as life’s three key “must have” (metabolism, reproduction, and evolution) were hardly measurable.
Nevertheless, NASA did not back down: as metabolism needs water, water became the first criteria to address NASA’s search for life in space. It was in this way that, around 10 years ago, the “follow the water” process started. By 2018, Dr. Green is clearly admitting that NASA has still not found any life yet, but at the same time he proudly informed his public that terrific progress has been made, especially in NASA’s ability to steer and orientate its quest for life. Moreover, while doing so, NASA has also collected an incredible amount of data on all the major bodies in the solar system, by now being able to model planets’ and moons’ evolutions over time.
As a result, NASA scientists can now analyze the past evolution of planets such and Mars and Venus. Both planets – Dr. Green explained – were in the past way more similar to the Earth. However, over the past hundreds of millions of years their atmospheric conditions deeply changed, making them inhabitable today. These observations are incredibly interesting for two reasons. On the one hand, the study of such changes can provide useful insights in evaluating where our planet is headed. On the other hand, this is also of utmost relevance for NASA’s quest for life, as life could have well been present on Mars and Venus, for instance, before their recent atmospheric changes.
Also, Dr. Green described one of NASA’s most tantalizing findings, that is, distant planets that have been often considered inhabitable due to their icy surfaces might well be hosting forms of life. For bodies such as Enceladus and Titan, superficial ice might indeed just be a crust, under which oceans might be existing and fostering life. In order to follow up on these and many other findings, NASA is now planning a series of missions (e.g. to Venus, Europa, Titan, and the Saturn system), especially thanks to the “tremendous support from the American people.”
Questioned by the audience, Dr. Green also answered a series of interesting questions. Questioned about NASA’s budget, Dr. Green expressed its satisfaction with the current sums available, expected to amount to $20 billion for next year only. Moreover, as privates seems to get more and more interested in the business of space, Dr. Green expressed his will to collaborate with the private sector. Such collaboration – he explained – could enable NASA to spare some efforts and money, thus unlocking the organization’s potential to expand its reach into more cutting-edge research domains. Similarly, Dr. Green stressed the profitable cooperation that NASA enjoys with the European Space Agency (ESA) and the US Department of Defense, recently tasked by the US President to establish a military space force.
Finally, Dr. Green, asked by the audience about specific projects, discussed some of NASA’s upcoming activities, such as the Europa Clipper mission and the Lunar Orbital Platform Gateway. More specifically on NASA’s Mars program, Green announced the organization’s next step, that is, to be able to bring back to our planet samples from Mars surface. When analyzed with NASA’s technological equipment as it is available on Earth, such samples might well provide interesting insights on possible forms of life living in Mars in the past.
While we conduct our daily lives as if nothing was happening, we might want to keep in mind the incredibly important researches that Dr. Green and his colleagues are daily, restlessly working on. The discoveries that NASA is making now – Dr. Green said – “are not going to appear in textbooks for perhaps many years.” Luckily, at least they are going to be in some newspapers and magazine. To all the people interested: food for thought is up for grabs.
