NASA launches its biggest space probe to find if life can exist on Jupiter moon
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Ali Martin Staff writer
Could life exist elsewhere in the universe?
Scientists are one step closer to discovering whether earthlings are alone in the universe, as NASA鈥檚 largest and most technologically advanced planetary spacecraft, the Europa Clipper, launched on Oct 14. The Clipper will head for Europa, one of Jupiter鈥檚 95-plus moons, to find out if that celestial body holds the conditions for life as we know it here on Earth.
The Clipper is 10 years in the making, and will take 5 陆 years more to get to Europa. Over the course of 49 flybys that will take 3 陆 years, the Clipper will send back data allowing scientists to examine Europa鈥檚 oceans, rock, and atmosphere. Scientists believe the oceans, in particular, are similar to Earth鈥檚 and will be a good indicator for the possibility of life there.
Why We Wrote This
A story focused onThe launch of the Europa Clipper mission to a potentially habitable celestial body 鈥� a moon of Jupiter 鈥� is a leap forward in the quest to answer one of humanity鈥檚 greatest questions: Is there life beyond Earth?
has been part of the Clipper mission since its inception. The planetary geologist and Clipper project staff scientist talked with the Monitor about the mission鈥檚 science and goals, and what it all means for humanity.
The discussion has been edited for clarity and length.
What exactly are you looking for? What will indicate conditions for life?
There鈥檚 this question of whether you have some sort of nutrient cycling on Europa that might be able to sustain life.
The simplest way I explain it is: water plus rock plus energy plus time. We have water, which we think is like our ocean water on Earth. We think there鈥檚 a rocky interior 鈥� Europa鈥檚 core 鈥� that鈥檚 in contact with that subsurface ocean. That water-rock interaction is what鈥檚 producing that chemistry that you need for life potentially. That鈥檚 how we think life originated on Earth; at these mid-ocean ridges on Earth where you had the ocean water in contact with rock, in contact with heat and magma coming out of Earth鈥檚 interior.
The energy for Europa is generated through its slightly elliptical orbit around Jupiter. It causes Europa to almost breathe or flex, and that flexing generates a lot of heat in the rocky interior and then it has to come out. We think this has all been simmering together for 4 billion years. And we don鈥檛 know how long it takes for life to originate. It could be instantaneous. It could be a billion years. That鈥檚 why it鈥檚 important that we have that time component.
What are the questions about habitability?
A lot of that is about the stability and the composition of the ocean. We think it鈥檚 salty. We don鈥檛 know exactly what salts are in there or are there organics in there also. That鈥檚 a really important chemical piece for habitability. If you think about it, life might be able to originate, and then it eats everything. And if those nutrients aren鈥檛 refreshed it鈥檚 going to die. And so there has to be a cycle, a nutrient cycle also within Europa. And we think that may come from the young surface.
Europa鈥檚 surface is so young, about 100 million years old. Earth鈥檚 surface is about 200 to 300 million years old. We think that there could be some essence of plate tectonics going on in [Europa鈥檚] icy shell that鈥檚 refreshing the surface. Oxidants in the harsh radiation environment actually produce oxidants on the surface that can then be transported in the ice shell and then into the ocean. That may provide this nutrient conveyor belt, if you will, to help refresh nutrients in the ocean that may sustain life.
NASA
What does that mean to us on Earth if life can exist on other planets, other moons?
It鈥檚 such an amazing, big question: Are we alone? And I think it鈥檚 amazing from both a fundamental humanity perspective and also from a very scientific perspective. We have one data point for life in the universe. We don鈥檛 know if we鈥檙e special and unique or if we are more common than we thought.
If we deem Europa habitable, we need to go and understand whether it鈥檚 actually inhabited, right? And there鈥檚 important implications. If it鈥檚 inhabited, maybe we understand how life originates and maybe we鈥檙e not alone in the universe. And maybe life is really common. And that would blow my mind, right? And if it鈥檚 not inhabited but we deem it to be habitable, then maybe we鈥檙e missing something. Maybe we don鈥檛 know how life really originated on Earth. We鈥檙e missing some piece to the puzzle. And it鈥檚 really hard when you only have this one data point of Earth to understand how life originates, where life might originate, and therefore whether we鈥檙e alone in our solar system or alone in the universe.
There鈥檚 also this larger philosophical question of whether we understand life at all. Does life have to originate in a way that it originated on Earth?
What are you most looking forward to discovering?
I鈥檓 excited for the answers to the questions that we don鈥檛 even know to ask yet. We think we know some stuff about Europa. But we鈥檙e going to learn so much and discover so many things with this very capable and amazing spacecraft that I don鈥檛 even know what those questions are yet.
This is a generational mission. Not only do we do it for ourselves, but we do it for the next generation. I use Voyager 2 and Galileo data still, data that鈥檚 coming up on 50 years old and 20 years old. Not only do we do missions like this for our own scientific curiosity, but also to produce these datasets that are going to last for generations to come. And that is also just so cool to think about. It鈥檚 an exciting responsibility. It鈥檚 also a big responsibility to make sure that you鈥檙e producing these datasets that are going to be valuable for generations to come.
