Europa

Ocean on Jupiter’s moon ‘could be habitable,’ researchers say

With NASA slated to explore Jupiter’s moon Europa sometime in the next decade, researchers are increasingly confident that the ocean on the celestial satellite “could be habitable.” Speaking at the 2020 Goldschmidt Conference earlier this month, NASA researchers said they have developed a model that shows Europa, the sixth largest moon in the Solar System, could support life. “We were able to model the composition and physical properties of the core, silicate layer, and ocean,” NASA JPL researcher and the study’s lead author, Mohit Melwani Daswani, said in a statement. “We find that different minerals lose water and volatiles at different depths and temperatures. We added up these volatiles that are estimated to have been lost from the interior, and found that they are consistent with the current ocean’s predicted mass, meaning that they are probably present in the ocean.” The ocean is under a dense layer of frozen crust that is largely believed to be at least six and as many as 19 miles thick. The surface temperature on Europa is exceptionally cold as well, approximately -260 degrees Fahrenheit at the equator and -370 degrees Fahrenheit at the poles, according to Space.com. While the ocean is widely believed to be warm, researchers are only just learning that it likely formed due to the minerals being broken down by either tidal forces or radioactive decay, according to Universe Today. “Indeed it was thought that this ocean could still be rather sulfuric,” Daswani explained, “but our simulations, coupled with data from the Hubble Space Telescope, showing chloride on Europa’s surface, suggests that the water most likely became chloride rich. In other words, its composition became more like oceans on Earth. We believe that this ocean could be quite habitable for life.” In August 2019, NASA confirmed it would launch a mission to Europa, a trek that could answer whether the icy celestial body could be habitable for humans and support life. The Europa Clipper, which could launch as soon as 2023 but has a baseline commitment of a “launch readiness date by 2025,” will have a mass spectrometer on the craft, used to determine the mass of ions in an atom. The mission for the solar-powered Clipper is expected to cost around $4 billion, according to NASA. The space agency has previously said the purpose of the mission will be to investigate whether Europa, the sixth-largest of Jupiter’s 79 known moons, “could harbor conditions suitable for life, honing our insights into astrobiology.” A 2018 study expressed concerns that Europa’s surface may be extremely porous, which could harm any probe that touches down on its surface. In December 2019, a study suggested that if there is life on Europa, it would be indigenous to the moon and not related to humans.

Fascinating!!  For more on Europa, click on the text above.     🙂

NASA preparing mission to send lander to Europa, offering humanity’s best ever chance of meeting aliens

NASA might soon launch our best ever chance of meeting aliens. The space agency is putting together plans to send a lander to Europa, one of Jupiter’s moons and perhaps the most likely place to harbour extraterrestrial life anywhere near us. But first it will have to work out how it can actually land on a surface about which it knows next to nothing. The agency started seriously exploring the possibility by commissioning a report on the value of sending a lander onto the icy surface of the moon. That report has now arrived and NASA is looking to explore its findings with the scientific community. The mission’s work will be divided up into three goals. The first and most important will be the search for life, but the other two are to look at how habitable Europa might be, and to explore the possibility of future robotic exploration of the moon and its oceans. Scientists expect that Europa has a large saltwater ocean underneath the icy crust that we can see. That has twice as much water as the oceans on Earth do, scientists expect. Those circumstances and others have led scientists to conclude that Europe is probably one of the most likely places to find present-day life outside of Earth, and it is relatively close by. As such, scientists hope that the plan to send a life-detecting robot to the planet – the first time that has happened at NASA since the Viking mission more than 40 years ago. But they also have to cope with the fact that the icy surface of the moon is almost entirely unknown, and that it has no atmosphere and so can’t make use of things like a heat shield or parachutes. The lander is being prepared ready for after NASA’s solar-powered flyby of Europa is expected to launch in the early 2020s. That will be able to take a variety of high-definition images of the ocean and the icy shell that surrounds it, helping us learn more about the surface before sending a lander onto the planet.

Things that make ya go, “hmmmm…”      🙂

Jupiter moon Europa’s ocean may have enough energy to support life

Jupiter’s moon Europa might be able to support life even if there’s little or no volcanic activity under the satellite’s icy shell, a new study suggests. A salty ocean of liquid water is believed to lie beneath Europa’s icy exterior. Scientists think this ocean could be habitable, if it harbors the required chemical building blocks and the right proportion of elements to provide energy for biological systems — the right ratio of oxygen to hydrogen, for example. The new study suggests that there is, indeed, enough of that energy. A research team led by Steve Vance, of NASA’s Jet Propulsion Laboratory in Pasadena, California, found that, even without taking possible volcanic processes into account, Europa likely produces 10 times more oxygen than hydrogen, just as Earth does. According to the team’s calculations, Europa’s hydrogen is generated as seawater reacts with rock in the moon’s crust. Europa has cooled slowly over the eons, forming new cracks in the crust that expose more rock to seawater, thus generating more hydrogen, the researchers said. Meanwhile, the oxygen would come from ice on Europa’s surface. Radiation from Jupiter — which is far more intense than anything experienced on Earth’s surface — breaks water molecules into hydrogen and oxygen. The oxygen then reacts with other compounds in the water as well as the hydrogen. As the oxidants sink, they get recycled into Europa’s interior, and then into the ocean, study team members said. Until now, many planetary scientists thought that Europa, kneaded by Jupiter’s gravity, would be volcanically active. After all, the neighboring moon Io is the most volcanically active body in the solar system; Jupiter’s gravity and tidal forces deform Io’s crust and mantle, generating huge amounts of heat. Something similar could be happening at Europa, but nobody knows for sure if it is. Much speculation about possible Europan life envisions a biosphere that resembles the clusters of life found near hydrothermal vents on Earth’s ocean floor. But the new research suggests that volcanism isn’t necessary to cycle chemicals through the ocean, and thus is probably not necessary for living things to survive, study team members said. The study was published online in the journal Geophysical Research Letters.

Fascinating!!   🙂

Water, water everywhere in our solar system’s moons

The confirmation of a subterranean ocean underneath the icy surface of Jupiter’s moon Ganymede is the latest thread in a mounting body of evidence that water – and by theoretical extension, life – in our solar system need not be relegated solely to the narrow neither too hot nor too cold orbit known as the Goldilocks zone inhabited by Earth. With this confirmation, announced Thursday by NASA, Ganymede joins the ranks of two other moons that lie beyond the reach of the sun’s warmth and are believed to host underground reservoirs of liquid water. Evidence of similar oceans has been detected on Europa, another of Jupiter’s moons, and Enceledus, which orbits Saturn. This growing body of evidence that one of the key ingredients for life exists outside the range that was once considered to be the solar system’s only hospitable zone has prompted astronomers to completely rethink where and how they look for signs of life elsewhere in the solar system. “One of the things that we have learned in the last few decades is that life as we know it is not as we knew it,” says Nick Schneider, professor at the University of Colorado’s Department of Astrophysical and Planetary Science in Boulder, Colo. While the quest for evidence of microbial life in the solar system may seem inconsequential to Earthlings, discovery of any form of life, however small, could hold profound clues about the origin of life on our own planet, says Dr. Schneider, who was not involved in the Ganymede research, but serves as the instrument lead on the Imaging UltraViolet Spectrograph for NASA’s MAVEN mission to Mars. “I think that people will really come to accept this as the most profound question that we can ask,” he says. Astronomers first began to theorize that factors other than proximity to the sun could raise temperatures on other worlds to levels conducive to liquid water even before the first Voyager flybys around the Jupiter system in the 1980s, says planetary scientist Heidi Hammel, the executive vice president of the Association of Universities for Research in Astronomy (AURA) in Washington, D.C. “What we’re learning is that the sun and its warmth isn’t the only way to get warmth in the solar system and we’ve been thinking that for some time,” Dr. Hammel says. “However, there’s a difference between having a theory about something and having evidence that the model is correct.”

Indeed.  Very cool!    🙂