抖阴旅行射

Banner image: The SUDA instrument in a clean room at LASP.听(Credit: NASA/抖阴旅行射 Boulder/Glenn Asakawa)

Editor's note: Europa Clipper successfully launched Oct. 14.

As early as Oct. 10, a small piece of Colorado will begin its more than six-year journey to Jupiter鈥檚 mysterious moon Europa鈥攚hich, scientists believe, may harbor a vast ocean of water beneath its icy surface.

The SUrface Dust Analyzer is a $53 million instrument designed and built by a team at the (LASP) at 抖阴旅行射 Boulder. It鈥檚 one of nine instruments and a gravity science investigation flying to Europa aboard NASA鈥檚 flagship spacecraft. Europa Clipper will arrive at the moon in 2031 and, over the subsequent four years, will explore whether it has conditions that could support life.

SUDA is an important part of that search, said Sascha Kempf, principal investigator for the instrument. The apparatus is gold plated, weighs almost 35 pounds and is shaped like a bucket. As Europa Clipper swoops past the moon during its planned 49 flybys, SUDA will collect and analyze tiny particles of ice flying above the surface鈥攑otentially grabbing a taste of the hidden ocean below.

鈥淲here SUDA really flourishes is with detecting trace amounts of stuff embedded in ice,鈥� said Kempf, an associate professor at LASP and the Department of Physics.听

Europa Clipper is set to launch from NASA鈥檚 Kennedy Space Center in Florida on a SpaceX Falcon Heavy rocket.听

Here鈥檚 a closer look at the incredible SUDA instrument, by the numbers:

10,000 miles per hour

You can think of SUDA almost like a mobile chemistry laboratory for ice in space.

Here鈥檚 how it works: Europa is surrounded at all times by a cloud of ice particles鈥攂its of the surface that tiny meteorites have knocked into space. During flybys, SUDA will sweep through this cloud moving at speeds of around 10,000 mph, or roughly 4.4 kilometers per second, in some cases encountering thousands of particles in the process.

That鈥檚 fast鈥攕o fast, in fact, that those grains of ice will vaporize instantly when they hit an impact target at the back of SUDA.

鈥淭hat impact is so energetic that it actually ionizes the material,鈥� said Scott Tucker, SUDA project manager at LASP. 鈥淭he particles will break up into their molecular and atomic components.鈥�

SUDA will then extract those ingredients, focusing them toward a detector known as a time-of-flight mass spectrometer. Small building blocks, such as lone hydrogen ions, will reach the detector faster than heavier stuff, such as larger molecules. Bit by bit, SUDA will create a complete list of everything inside each grain of ice.

1 part per million

It鈥檚 remarkably sensitive. SUDA is capable of detecting a vast range of compounds that could be in Europa鈥檚 ocean鈥攆rom salts to much larger and more complex molecules like amino acids or fatty acids.

On Earth, those organic molecules are basic ingredients for life, although they can also be found in clouds of gas in space and other sterile environments. Scientists don鈥檛 know whether they exist on Europa. If they do, SUDA could identify them down to concentrations of just one part per million, and could even distinguish between different types of amino acids.

12 kilometers

The instrument鈥檚 detective work doesn鈥檛 stop there. When ice particles enter SUDA, they first pass through a sort of mesh that records their speed and orientation, Tucker said. With that information, researchers can recreate the path the particles took to reach the instrument.

鈥淲e can track the ballistic trajectories of the particles back to the ground,鈥� he said.

In other words, they can find where the ice came from on the surface of Europa鈥攊n some cases, to within 12 kilometers (7.5 miles).

That, in turn, will allow the researchers to put certain regions of the moon under the microscope. Hsiang-Wen (Sean) Hsu, the deputy principal investigator for SUDA, is especially eager to study two regions known as . They are what geologists call 鈥渃haos regions,鈥� places where huge slabs of ice have broken through the moon鈥檚 normally smooth surface鈥攁 sign that ocean water may be welling up from below.

鈥淏y measuring the composition of materials from those regions, we can actually get a peek at the processes occurring below the surface,鈥� said Hsu, a research scientist at LASP.

250 nanometers

The researchers also have to ensure that the impact target at the back of SUDA is incredibly clean鈥攖hey don鈥檛 want any atoms or molecules from Earth flying off when particles hit this target, contaminating data from Europa.听

To achieve that feat, the SUDA team got some help from scientists at JILA, a joint research institute between 抖阴旅行射 Boulder and the National Institute of Standards and Technology (NIST). The group figured out a way to coat the impact target at the back of SUDA in a layer of ultra-pure iridium metal just 250 nanometers thick, or hundreds of times thinner than the width of a hair.听

Iridium is among the densest metals on Earth, which means that it won鈥檛 break apart easily, even when it takes a pummeling in space.

27 months

For now, the team will have to wait. The researchers won鈥檛 be able to open SUDA鈥檚 door until after Europa Clipper crosses Mars鈥� orbit for the last time a little more than two years from now鈥攁t that point, they can begin sampling particles of dust in space to check that the instrument is performing as expected.

Tucker, however, is eager for the launch. He鈥檚 traveling to Florida in October to watch the spacecraft blast off with more than 20 people from LASP and around 10 SUDA team members from other institutions.

鈥淚'm really excited,鈥� he said. 鈥淥f course, you're always a little nervous when a launch comes up.鈥�

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Managed by Caltech in Pasadena, California, JPL leads the development of the Europa Clipper mission in partnership with the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, for NASA鈥檚 Science Mission Directorate in Washington. The Planetary Missions Program Office at NASA鈥檚 Marshall Space Flight Center in Huntsville, Alabama, executes program management of the Europa Clipper mission.