Planetary scientist and astrobiologist Kevin Peter Hand has been a member of the National Geographic family since 2011, and his field work has taken him to the most extreme environments on Earth. Working in NASA’s Jet Propulsion Laboratory (JPL), Hand and his team have created technology that is capable of traveling millions of miles through space in an effort to determine whether there is life beyond Earth.
NASA’s Galileo mission, launched in 1989, led scientists to believe there is a subsurface ocean on Jupiter’s fourth largest moon, Europa. This distant ocean may harbor conditions suitable for life as we know it. In order to assess whether there are habitable environments in alien oceans, Hand conducts his research in the deepest parts of our own ocean and in our planet’s harshest climates.
Hand will be sharing how his team’s discoveries could provide insight on whether we are actually alone in the universe at tonight’s Exploring Ocean Worlds event at the National Geographic headquarters in Washington, D.C. Before he takes the stage, he answered some questions we had about ocean and space exploration:
Our panel will discuss the distinct possibility of other ocean worlds existing in our solar system. Where in our solar system are these worlds present?
The ocean worlds of the outer solar system exist beneath the icy shells of moons orbiting Jupiter and Saturn, and possibly even moons of Uranus and Neptune. These are worlds with names like Europa, Ganymede, Callisto, Enceladus, Titan and Triton. The first three are moons of Jupiter, the next two are moons of Saturn, and the last one, Triton, is a moon of Neptune. In all cases, vast liquid water oceans may exist beneath their icy shells. If we have learned anything from life on Earth, it’s that where there is liquid water, there is life. These oceans harbor a tremendous volume of liquid water — might they be habitable or inhabited? We’ve just got to go and explore.
What sort of technology is necessary to explore the possibility of life beyond Earth?
Well, a complete answer to this question would have to cover everything from the rocket needed for launch, to the spacecraft needed to land, to the instruments needed to make the measurements. I’ll spare you the details on what it takes to get to these worlds and instead I’ll focus on the types of measurements that could be useful once we’re there. For the most part, when we talk about the search for life within these ocean worlds, we’re talking about the search for single-celled, microbial life. To search for signs of microbial life you need instruments that can look for the physical signs — e.g., cameras and microscopes — and you need instruments that can look for the chemical signs — e.g., spectrometers that can measure organic compounds and reveal the elemental and molecular makeup of a sample. Combining several instruments and several types of measurements is critical, as any single measurement could yield ambiguous or confusing results.
Importantly, a lot of the instruments and tools that we envision using on these distant worlds have their heritage from similar devices used on Earth and in our ocean.
Would you say that this technology could be used to explore our own ocean as well? What kind of overlap or commonalities do space exploration and ocean exploration share?
There is a lot of overlap, and we are working hard to bridge the oceanographic community with the planetary science and astrobiology community. Devices that are being used on Earth can be adapted for use on these future missions, and some of the advancements we’ve made in space can be adapted to advance exploration in our own ocean.
As just one example, JPL and Woods Hole Oceanographic Institution are partnered up on developing a small robotic vehicle that will get us back to the deepest region of our ocean (the Mariana Trench). This new vehicle uses a number of technologies that were originally developed for space exploration and the construction of small satellites called “cubesats.” We’re essentially building “cubesats for the sea.” The low-mass, low-power, small-volume devices that make cubesat useful in space also make those devices very useful in our ocean.
Another example is autonomy — getting robots to do things on their own. In space, we have to use autonomy for a number of functions because once the robot is launched, there is no getting it back; it must do certain things on its own. In the exploration of our ocean autonomy, it’s often easier to just pull the robot back onto the ship and fix the problem, rather than to have the robot be intelligent enough to figure it out on its own. Our teams are trying to bridge how autonomy is being used across three different robotic platforms — from our ocean to oceans far out in the solar system.
Similarly, what are some not-so-obvious differences?
A key difference is where the science gets done. Usually when science teams go out to explore our ocean, the scientists collect samples and bring them back to the lab — it’s a sample return mission. In space, sample return missions are hard, expensive and very rare. We have to do the science on the planet or moons to which we have sent the robot. This requires the scientists and engineers to build robust instruments that can make the measurements on these worlds. One of the things we’re trying to do is to bring some of that mentality to the exploration of our ocean: do more science in real-time in the ocean with an instrumented robotic vehicle. We’ve got a long ways to go, but it’s another great example of how we’re trying to bridge the exploration of Earth’s ocean with oceans beyond Earth.
As an astrobiologist, you are understandably an advocate for space exploration. However, many would argue we should be using our resources to explore our own ocean. Would you say both forms of exploration influence each other?
One of the great aspects of our efforts to explore oceans beyond Earth, such as Europa’s ocean, is that we have a win-win of simultaneously improving our ability to explore our ocean here on Earth. The robots and instruments that will someday get into Europa’s ocean will have their heritage in Earth’s ocean. The robots that are now exploring Mars have their heritage from robots that were developed to explore old, rocky terrains on Earth. A lot of investment went into that. Similarly, the submersibles and instruments that will someday explore Europa, Enceladus and Titan will have their roots in vehicles built to explore Earth’s ocean. We’re starting to make those investments now, and I think that in the next few decades we’ll see a significant leap in our capability to explore our ocean with small, low-power, autonomous robots that are the precursors to robots that will someday explore the oceans of the outer solar system.
Finally, your research has taken you from the depths of the ocean to Mount Kilimanjaro; are you able to pick one defining experience? What has most inspired you and your work?
Ooh, tough question. I’ve been very fortunate to see so many different, amazing places on our home planet — from the Dry Valleys of Antarctica to the far northern reaches of the Arctic Ocean. Hard to pick one, but I’d have to go with a dive that I made along the Mid-Atlantic Ridge at a site called Snake Pit. It’s a very active hydrothermal region with chimneys gushing out black, chemically rich fluids. Around these chimneys we saw an incredible cyclone of shrimp, buzzing and darting like bees at a hive. It was astounding. Here we were in one of the deepest, darkest, most extreme environments on Earth, and life was thriving. Experiences like that lead me to predict that we likely live in a universe rich with life of all shapes and sizes.