Is there life orbiting Jupiter?
By Patrick Gasda
Extremely cold and bombarded by intense radiation, Jupiter’s moon Europa seems like one of the last places in the solar system to look for life. But Europa could hold organic material yet undiscovered and an ocean hiding deep below its thick, frozen crust.
To help NASA with its interplanetary research, Los Alamos National Laboratory is designing a prototype instrument capable of withstanding the extreme conditions on Europa. It is proposed for an upcoming mission to Jupiter’s moon. The goal is to deepen understanding of this tantalizing world and extend the search for life in the solar system.
Los Alamos scientists have plenty of history helping NASA explore another world for evidence of habitability and ultimately of life. In the early 2000s the first neutron spectrometer — developed by the laboratory — orbited Mars, discovering and mapping its vast water resources. More recently they designed ChemCam, a combination of lasers, spectrometers, a telescope, and a camera that piggybacked on the Mars Curiosity rover to study Martian rocks and helped find evidence for a habitable Mars in the past.
The Los Alamos team is now testing SuperCam, a souped-up version of ChemCam set to join the Mars 2020 mission with a camera, laser, spectrometers, and microphone to identify chemicals and minerals on the red planet.
ChemCam, SuperCam and OrganiCam leverage the lab’s work in radiation hardening of satellites, space-based detection and development of unique sensors such as those used for global security and nonproliferation.
The lab is collaborating with colleagues at the University of Hawaii and in France on OrganiCam, which uses a fluorescence-spectrometer similar in some ways to the one on SuperCam. Researchers are designing OrganiCam to identify possible organic materials on Europa. Once it arrives after its long journey, the instruments will get straight to work. Its pulsed laser will illuminate a large area and its super-fast camera will make a panorama in search of a nanosecond-brief fluorescence signal, glowing for a fraction of a second under the laser’s light.
OrganiCam’s spectrometer does two things: First, based on spots identified in panoramic fluorescence images, it detects the unique fluorescence signatures categorizing any organic materials present. If something glows with a nanosecond lifetime, it’s probably organic, and if it’s organic, it could be bacteria — life. Next, using Raman spectrometry, it identifies materials by their “fingerprint” spectra. Once glowing targets are identified by OrganiCam, the lander will stretch out its two-meter-long arm, scoop up samples and bring them inside for further analysis. Finally, the lander will send data up to an orbiter, which will relay the information to waiting scientists back on Earth.
So what makes researchers think life might exist in such an inhospitable environment? Since NASA began fly-by missions to Europa in the late 1970s and the Hubble Space Telescope saw possible water plumes in 2012, they’ve suspected the presence of hidden, subsurface liquid. NASA’s recent new analysis of information gathered by the Galileo spacecraft in 1997 adds to the evidence of an ocean.
Furthermore, tidal heating — an effect of Jupiter’s powerful gravity on Europa’s rocky interior and metallic core — is thought to warm the interior ocean and rocks. This heating may cause vents to form on Europa’s seafloor, similar to black smokers on the Earth’s seafloor, where this environment supports life and may be where life started. Scientists also plan to measure levels of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, the building blocks of life, up there on that frozen moon.
Simple, right? Not so fast — the challenges are many. For one thing, temperatures on Europa range from minus 300 degrees at night to minus 240 degrees during the day. By comparison, the warmest day on Europa is colder than the coldest night on Mars and colder than any spot imaginable on Earth.
As if the cold wouldn’t be hard enough on OrganiCam’s components, intense radiation slamming Europa from Jupiter’s huge magnetic field could darken the camera’s lenses, reducing the ability to collect usable data. High radiation could also cause OrganiCam’s electronics to fail. That’s where the lab’s expertise in designing, testing and building radiation-tolerant devices comes in. Lab scientists plan to evaluate the effects of that exposure on the instruments by exposing them to Europa-level radiation in the beam at the Los Alamos Neutron Science Center.
OrganiCam is expected to work for about 20 days. Its operational life is limited by its power source, but Europa’s harsh conditions will also quickly erode its performance. Though scientists may have to wait some years for results from OrganiCam, if all goes well, Europa may prove to be one of the best places in the solar system to look for life.
Patrick Gasda is a staff scientist in the Space Science and Applications group at Los Alamos National Laboratory. As a member of the OrganiCam team, he works with team leader Roger Wiens to study the geochemistry and astrobiology of Europa. The concept phase of OrganiCam is being funded by Laboratory Directed Research and Development funds and the Center for Space and Earth Science at Los Alamos National Laboratory.
This story first appeared in Santa Fe New Mexican.
