Is the fountain spewing from Europa? NASA’s Europa Clipper Is In The Case – Are You Happy With That?
Finding the beams in Europa is an exciting prospect, but scientists warn it will be complicated, even up close.
In 2005, images of a brilliant jet of water spewing from the surface of Saturn’s moon Enceladus captivated the world. Massive column of water vapor, ice particles and organic molecules spewing from the moon’s south pole suggests an ocean of liquid water beneath Enceladus’ ice crust and confirms that the moon is active geologically. The outflow also pushes Enceladus and other worlds in the outer solar system, which has no atmosphere and is far from the heat of the Sun, to the top of NASA’s list of places to look for signs of life.
Scientists are currently preparing for a mission to another ice cover ocean world possible: Jupiter’s moon Europa. Scheduled to launch in 2024, NASA’s Europa Clipper spacecraft will study the moon from deep within to its surface to determine if it has the ingredients that make it a viable home for life. or not.
Like Enceladus, Europa is geologically dynamic, meaning that both moons generate heat internally as their solid layers stretch and flex from the gravitational tug with their host planets and their neighboring moons. This, instead of heat from the Sun, keeps the subsurface water from freezing on these ice-covered moons. Heat can also help produce or circulate the chemical building blocks of seafloor life, including carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur.
But that’s where the similarities end.
“Many people think Europa will be Enceladus 2.0, with beams constantly spewing from the surface,” said Lynnae Quick, a member of the science team behind Clipper’s Europa Imaging System (EIS) camera. “But we can’t see it that way; Europa is a completely different monster,” said Quick, who is based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
One of the first images of Enceladus’ water jets was taken by NASA’s Cassini spacecraft on November 27, 2005. In this image, Enceladus is backlit by the Sun. Vendor: NASA / JPL / Institute of Space Science.More information here.
Evidence suggests that Europa can drain water from its surface just like Enceladus. For example, scientists use NASA’s Galileo spacecraft, NASA’s Hubble Telescope, and vast Telescopes on Earth reported detecting faint jets or their chemical compositions at Europa.
But no one is sure. “We’re still in space where there’s really compelling evidence but none of it’s a murder,” he said. Matthew McKay Hedman, a member of Europa Clipper’s Mapping Imaging Spectrometer for Europa (MISE) science team and associate professor in the Department of Physics at the University of Idaho.
Scientists are attracted to plumes for a few reasons. First, there’s no denying them cool: “We’re scientists, but we’re also humans,” says Shawn Brooks, who is working with Europa Clipper’s Europa Ultraviolet Spectrometer (Europa-UVS) science group and is based in NASA’s Jet Propulsion Laboratory in Southern California said.
But more realistically, says Brooks, the plumage gives scientists easier access to Europa’s interior. “It all depends on whether Europa is habitable, and that depends on having some understanding of what’s going on below the surface, which we don’t have yet.” he said.
In other words, the magic of Europa, a prototype for a habitable world, is hidden from view deep within the moon. Compared to Enceladus, which is about the size of Texas, Europa is one-quarter the size of Earth, or slightly smaller than Earth’s moon. And evidence suggests that Europa has a much deeper saltwater ocean than Enceladus, possibly 40 to 100 miles (about 60 to 160 km) deep, meaning it could hold twice as much water as the ocean above. Earth. Some scientists theorize that Europa’s ocean may react to the superheated rocks beneath its seafloor, possibly through hydrothermal vents. On Earth, such regions are hotspots of chemical activity that feed a multitude of organisms.
There may also be large pockets of meltwater in Europa’s ice crust, scientists say, more likely than the ocean as the source of the beams. These bags can also create a cozy habitat for the creatures.
Because it is closer to Jupiter than Enceladus is near Saturn, more heat is generated at Europa due to friction generated as it orbits its host planet. Because internal heat stimulates geological activity on rocky worlds, Europa is thought to be geologically broader than Enceladus. Some scientists predict that Europa has tectonic plates that change and recycle the icy blocks that make up the lunar surface. If so, Europa could be circulating nutrients produced on the surface by radiation from Jupiter, such as oxygen, to pockets of liquid in the ice crust or possibly to the ocean itself. Through the Europa Clipper, scientists will have the opportunity to test some of their predictions by analyzing the chemical composition of the plumes or the marks they may leave on the surface.
This composite image shows plumes of water vapor suspected of erupting at 7 o’clock on the edge of Jupiter’s moon Europa. The beams, captured by NASA’s Hubble Space Telescope Imaging Spectrograph, are seen as silhouettes as the moon passes in front of Jupiter. The Hubble data was collected on January 26, 2014. The image of Europa, superimposed on Hubble’s data, was obtained from data from the Galileo and Voyager missions. Vendor: NASA / ESA / W. Spark (STScI) / USGS Center for Astronomical Sciences.More information here.
Scientists warn that Europan plumes, even if they are there, can be difficult to detect even up close. They can be discrete, and can be small and thin, because Europa’s gravity, much stronger than Enceladus’, will likely keep these plumes close to the surface. It was a dramatic departure from Enceladus’s spectacular column of vapor: It was always above and larger than the moon itself, spewing icy particles hundreds of miles above the surface. “Even if they were there, Europa’s plumage might not be so photogenic,” says Hedman.
Although Europa Clipper scientists are devising many innovative strategies to find active beams when the spacecraft begins to explore Europa in 2031, they are not relying on them to understand what is happening. inside the moon. “We don’t have to capture one to do a successful mission,” Quick said.
Quickly add that every musical instruments on Clipper could contribute evidence of habitable conditions below the surface regardless of active beams.
A few examples of how the team would look for potential beams include Europa Clipper’s camera set, EIS. It will detect beams of light near Europa’s surface in part by looking for their shadows at Europa’s limb or edge, as the moon is illuminated by Jupiter’s light as it passes in front of the planet. The EIS will take pictures of plumes if they are present, as well as visible plaques on the surface. NS Europa-UVS will also attempt to detect beams in ultraviolet light, including at the moon’s edge as Europa passes in front of nearby stars, and it can measure the chemical composition of such beams. A thermal camera, Europa Thermal Emission Imaging System (E-THEMIS), will look for hot spots on the surface that could be evidence of active or recent eruptions.
The Europa Clipper team is set to succeed whether or not researchers find the beam in Europa, although many scientists hope for a spectacular underwater show to enrich the mission and our understanding of Europa. “I suspect Europa is active and letting some matter escape,” Hedman said. “But I hope that when we really understand how it does it, it won’t be what people expect.
Life as we know it needs liquid water. Astrobiology, a field of science and engineering that describes efforts to find the components of life beyond Earth, is the search for planets, dwarf planets, and moons that contain substantial liquid water. Scientists call these places “the ocean world”. Source: NASA’s Goddard Space Flight Center.
More information about the mission
Missions like Europa Clipper contribute to the field astronomy, the interdisciplinary study of the variables and conditions of distant worlds that could harbor life as we know it. Although Europa Clipper is not a life-detecting mission, it will conduct detailed reconnaissance of Europa and investigate whether the icy moon, with its subsurface ocean, is capable of supporting life. . Understanding Europa’s habitability will help scientists better understand how life evolved on Earth and our potential for finding extraterrestrial life.
Managed by Caltech in Pasadena, California, JPL led the development of the Europa Clipper mission in partnership with the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, for NASA’s Science Mission Directorate in Washington. The Planetary Missions Program Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama, performs program management of the Europa Clipper mission.
More information about Europa can be found here:
Banner image caption: Left is a view of Europa taken on March 2, 1979, by the Voyager 1 spacecraft. Next is a color image of Europa taken by the Voyager 2 spacecraft during the collision its proximal forehead on July 9, 1979. Right is an image of Europa created from images taken by the Galileo spacecraft in the late 1990s. Image credit: NASA/JPL. Download images of Europa here
Via Lonnie Shekhtman
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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