From Johns Hopkins University (US) via : “Europa Clipper to determine whether icy moon has ingredients necessary for life”

From Johns Hopkins University (US)


July 5, 2021
Ashley Stimpson, Johns Hopkins University

Credit: Eric Nyquist.

In 1610, Galileo peered through his telescope and spotted four bright moons orbiting Jupiter, dispelling the long-held notion that all celestial bodies revolved around the Earth. In 2024, when scientists expect to send the Europa Clipper spacecraft to investigate one of those moons, they too may find evidence that fundamentally alters our understanding of the solar system.

Europa is the sixth nearest moon to Jupiter and is roughly the same size as our own. Thanks to data retrieved by the Galileo space probe—launched in 1989 and named to honor the Italian astronomer—and the Hubble Space Telescope, scientists are almost sure that a salty, liquid ocean is hidden beneath Europa’s icy surface, one so large that astronomers believe it could contain two times the water in all of Earth’s oceans combined.

Europa itself has been around for 4.5 billion years, but its surface is geologically young, only about 60 million years old, suggesting that it has been continually resurfaced, perhaps through a process much like Earth’s shifting plate tectonics. As Europa travels around Jupiter, its elliptical orbit and the planet’s strong gravitational pull cause the moon to flex like a rubber ball, producing heat that’s capable of maintaining an ocean’s liquid state. Hydrothermal energy at the moon’s core, left over from its formation, may also heat the ocean at the seafloor.

These unique characteristics have led NASA to deem Europa “the most promising place in our solar system to find present-day environments suitable for some form of life beyond Earth.” But in order for life to exist, it needs more than just water and energy. It also needs essential chemicals like hydrogen, carbon, and oxygen. While Europa seems to check the first two boxes, its composition remains a mystery. Confirming all three of these ingredients for life will determine whether Europa is habitable.

“That’s the $4 billion question,” says Haje Korth, a space physicist at the Johns Hopkins Applied Physics Lab and deputy project scientist for the Europa Clipper mission. He and his colleagues at NASA and its California-based Jet Propulsion Lab are gearing up to investigate whether Europa might contain the ingredients necessary for life somewhere in its vast ocean.

In late 2024, they will send the orbiter into the skies above Cape Canaveral, where it will begin its five-and-a-half-year journey to Europa. During that time it will fly by both Mars and Earth, using the planets’ gravity to slingshot itself 484 million miles toward Jupiter, arriving by 2030. Kate Craft, one of the mission’s project staff scientists, warns the long journey will precede even greater challenges.

“The radiation from Jupiter is really harsh,” she says. “Our instruments have to be able to survive that.”

Alien Ocean: NASA’s Mission to Europa. Credit: JHU.

Roughly the size of a basketball court, the Europa Clipper will carry an impressive suite of 10 separate instruments. Korth says getting all those gadgets to work simultaneously—in the frigid temperatures of outer space, no less—will be another test.

Two cameras, so powerful they will be able to pick up features just a few feet long, will map the moon’s surface in color and from multiple angles. Spectrometers will study the chemical makeup of Europa’s surface as well as the particles that hover above it. A magnetometer will be able to determine the depth and salinity of Europa’s ocean.

Two more instruments, a thermal emission imaging system and an ultraviolet spectrograph, will look for areas where Europa’s ocean may have spilled out onto the surface via eruptions or plumes. If scientists find such a location, they would be able to analyze the composition of Europa’s ocean without ever touching down on its surface.

“These would be the most pristine samples of the ocean underneath,” Korth says. “This is not a plume-hunting mission, but we’ll certainly take that opportunity.”

Clipper will spend three and a half years in orbit around Jupiter, performing a flyby of Europa every two to three weeks from as close as 16 miles away, sending back observations that will reach Earth in as little as a week. Between flybys, scientists will pore over this cache of data, adjusting the observations if they see something that sparks their interest—a plume, for example—or necessitates further investigation. Right now, the mission team has planned 45 flybys, but the tour could be extended if funding allows.

While launch is still more than three years away, Craft is already part of multiple studies determining the feasibility and logistics of a Europa Lander mission, the next logical step if Europa Clipper finds the moon to be habitable. A lander could be delivered to Europa from a sky crane—much like the recent Mars Perseverance—and house a cryobot designed to drill through the icy shell and into the ocean below.

Europa’s subsurface waters aren’t the only outer-space oceans that APL has its eyes on. In October 2020, the Lab announced it would pitch NASA on the Enceladus Orbilander, a spacecraft designed to orbit and land on Saturn’s sixth-largest moon to search for signs of life hidden in its ocean.

See the full article here .


Please help promote STEM in your local schools.

Stem Education Coalition

Johns Hopkins Unversity campus.

The Johns Hopkins University (US) opened in 1876, with the inauguration of its first president, Daniel Coit Gilman. “What are we aiming at?” Gilman asked in his installation address. “The encouragement of research … and the advancement of individual scholars, who by their excellence will advance the sciences they pursue, and the society where they dwell.”

The mission laid out by Gilman remains the university’s mission today, summed up in a simple but powerful restatement of Gilman’s own words: “Knowledge for the world.”

What Gilman created was a research university, dedicated to advancing both students’ knowledge and the state of human knowledge through research and scholarship. Gilman believed that teaching and research are interdependent, that success in one depends on success in the other. A modern university, he believed, must do both well. The realization of Gilman’s philosophy at Johns Hopkins, and at other institutions that later attracted Johns Hopkins-trained scholars, revolutionized higher education in America, leading to the research university system as it exists today.

The Johns Hopkins University (US) is a private research university in Baltimore, Maryland. Founded in 1876, the university was named for its first benefactor, the American entrepreneur and philanthropist Johns Hopkins. His $7 million bequest (approximately $147.5 million in today’s currency)—of which half financed the establishment of the Johns Hopkins Hospital—was the largest philanthropic gift in the history of the United States up to that time. Daniel Coit Gilman, who was inaugurated as the institution’s first president on February 22, 1876, led the university to revolutionize higher education in the U.S. by integrating teaching and research. Adopting the concept of a graduate school from Germany’s historic Ruprecht Karl University of Heidelberg, [Ruprecht-Karls-Universität Heidelberg] (DE), Johns Hopkins University is considered the first research university in the United States. Over the course of several decades, the university has led all U.S. universities in annual research and development expenditures. In fiscal year 2016, Johns Hopkins spent nearly $2.5 billion on research. The university has graduate campuses in Italy, China, and Washington, D.C., in addition to its main campus in Baltimore.

Johns Hopkins is organized into 10 divisions on campuses in Maryland and Washington, D.C., with international centers in Italy and China. The two undergraduate divisions, the Zanvyl Krieger School of Arts and Sciences and the Whiting School of Engineering, are located on the Homewood campus in Baltimore’s Charles Village neighborhood. The medical school, nursing school, and Bloomberg School of Public Health, and Johns Hopkins Children’s Center are located on the Medical Institutions campus in East Baltimore. The university also consists of the Peabody Institute, Applied Physics Laboratory, Paul H. Nitze School of Advanced International Studies, School of Education, Carey Business School, and various other facilities.

Johns Hopkins was a founding member of the American Association of Universities (US). As of October 2019, 39 Nobel laureates and 1 Fields Medalist have been affiliated with Johns Hopkins. Founded in 1883, the Blue Jays men’s lacrosse team has captured 44 national titles and plays in the Big Ten Conference as an affiliate member as of 2014.


The opportunity to participate in important research is one of the distinguishing characteristics of Hopkins’ undergraduate education. About 80 percent of undergraduates perform independent research, often alongside top researchers. In FY 2013, Johns Hopkins received $2.2 billion in federal research grants—more than any other U.S. university for the 35th consecutive year. Johns Hopkins has had seventy-seven members of the Institute of Medicine, forty-three Howard Hughes Medical Institute Investigators, seventeen members of the National Academy of Engineering, and sixty-two members of the National Academy of Sciences. As of October 2019, 39 Nobel Prize winners have been affiliated with the university as alumni, faculty members or researchers, with the most recent winners being Gregg Semenza and William G. Kaelin.

Between 1999 and 2009, Johns Hopkins was among the most cited institutions in the world. It attracted nearly 1,222,166 citations and produced 54,022 papers under its name, ranking No. 3 globally [after Harvard University (US) and the Max Planck Society (DE)] in the number of total citations published in Thomson Reuters-indexed journals over 22 fields in America.

In FY 2000, Johns Hopkins received $95.4 million in research grants from the National Aeronautics and Space Administration (US), making it the leading recipient of NASA research and development funding. In FY 2002, Hopkins became the first university to cross the $1 billion threshold on either list, recording $1.14 billion in total research and $1.023 billion in federally sponsored research. In FY 2008, Johns Hopkins University performed $1.68 billion in science, medical and engineering research, making it the leading U.S. academic institution in total R&D spending for the 30th year in a row, according to a National Science Foundation (US) ranking. These totals include grants and expenditures of JHU’s Applied Physics Laboratory in Laurel, Maryland.

The Johns Hopkins University also offers the “Center for Talented Youth” program—a nonprofit organization dedicated to identifying and developing the talents of the most promising K-12 grade students worldwide. As part of the Johns Hopkins University, the “Center for Talented Youth” or CTY helps fulfill the university’s mission of preparing students to make significant future contributions to the world. The Johns Hopkins Digital Media Center (DMC) is a multimedia lab space as well as an equipment, technology and knowledge resource for students interested in exploring creative uses of emerging media and use of technology.

In 2013, the Bloomberg Distinguished Professorships program was established by a $250 million gift from Michael Bloomberg. This program enables the university to recruit fifty researchers from around the world to joint appointments throughout the nine divisions and research centers. Each professor must be a leader in interdisciplinary research and be active in undergraduate education. Directed by Vice Provost for Research Denis Wirtz, there are currently thirty two Bloomberg Distinguished Professors at the university, including three Nobel Laureates, eight fellows of the American Association for the Advancement of Science (US), ten members of the American Academy of Arts and Sciences, and thirteen members of the National Academies.