Take a closer look at the complex choreography involved in building NASA’s
Europa Clipper as the mission to explore Jupiter’s moon Europa approaches
its 2024 launch date.
The hardware that makes up NASA’s Europa Clipper spacecraft is rapidly
taking shape, as engineering components and instruments are prepared for
delivery to the main clean room at the agency’s Jet Propulsion Laboratory in
Southern California. In workshops and labs across the country and in Europe,
teams are crafting the complex pieces that make up the whole as mission
leaders direct the elaborate choreography of building a flagship mission.
The massive 10-foot-tall (3-meter-tall) propulsion module recently moved
from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, to the Johns
Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, where
engineers will install electronics, radios, antennas, and cabling. The
spacecraft’s thick aluminum vault, which will protect Europa Clipper’s
electronics from Jupiter’s intense radiation, is nearing completion at JPL.
The building and testing of the science instruments at universities and
partner institutions across the country continue as well.
The mission is also gearing up for its System Integration Review in late
2021, when NASA will review plans for assembling and testing Europa Clipper,
and its instruments are inspected in detail.
“It’s really exciting to see the progression of flight hardware moving
forward this year as the various elements are put together bit by bit and
tested,” said Europa Clipper Project Manager Jan Chodas of JPL. “The project
team is energized and more focused than ever on delivering a spacecraft with
an exquisite instrument suite that promises to revolutionize our knowledge
of Europa.”
Jupiter’s icy moon Europa, which harbors an internal ocean with twice the
amount of water in Earth’s oceans combined, may currently have conditions
suitable for supporting life. Europa Clipper will carry a broad suite of
science instruments into orbit around Jupiter and conduct multiple close
flybys of Europa to gather data on its atmosphere, surface, and interior.
Hardware in the Works
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| Europa Clipper’s spectrometer, Mapping Imaging Spectrometer for Europa (MISE), is seen in the midst of assembly in a clean room at NASA’s Jet Propulsion Laboratory. MISE will analyze infrared light reflected from Europa and map its surface composition in detail. |
Delivery of the towering propulsion module from Goddard to APL marked a
milestone for that major piece of hardware. APL built the twin cylinders
that make up the module and shipped them to JPL, where technicians added
thermal tubing that will carry coolant to keep the spacecraft from getting
too hot or too cold in deep space. From there, the cylinders went to
Goddard, where propellant tanks were installed inside of them and 16 rocket
engines were attached to the outside.
Another large piece of hardware nearing completion is the spacecraft’s
radiator, which connects to the thermal tubing. The width and length of a
twin-size bed, the radiator’s 3-inch-thick (7.5-centimeter-thick) panel has
the crucial job of radiating heat out into space to keep the spacecraft
within its operating temperature range. It is covered with louvers that open
and close automatically as the spacecraft disperses more or less heat to
regulate its temperature.
Meanwhile, work at APL begins to integrate the propulsion module and the
telecommunications hardware (electronics, radios, antennas, and cabling).
And construction of a high-gain antenna – a dish nearly 10 feet (3 meters)
wide – is underway at vendor Applied Aerospace Structures Corporation in
Stockton, California. It will be delivered to APL this year, where it will
be integrated before the entire module comes back to JPL a final time. By
the spring of 2022, the huge element will join other Europa Clipper hardware
streaming into JPL’s main high bay for assembly, test, and launch operations
(ATLO).
One of the first elements in place for ATLO will be the spacecraft’s vault,
now entering its final stage of fabrication at JPL. Eventually, the vault
will be bolted to the top of the propulsion module and affixed with miles of
cabling so that the power box and computer inside can communicate with the
other subsystems.
Attached to the vault will be a deck, also completing assembly at JPL, that
will support many of the instrument sensors. Called the nadir deck, it
stabilizes the spacecraft’s sensors and helps ensure they are oriented
correctly.
Science Instruments Nearing Completion
At the same time that the spacecraft body, electronics, and engineering
subsystems come together, nine science instruments are being assembled and
tested across a network of clean rooms at NASA centers, partner
institutions, and private industry vendors. The suite of instruments will
investigate everything from the depth of the internal ocean and its salinity
to the thickness of the ice crust and potential plumes that may be venting
subsurface water into space.
Slated to be delivered to ATLO from late 2021 through mid-2022, the
instruments, which include cameras to capture surface geology in detail, are
undergoing extensive testing. Engineers want to be sure the instruments can
communicate correctly with the flight computer, spacecraft software, and the
power subsystem, to be able to respond to commands and transmit data back to
Earth.
Mission leaders acknowledge that COVID-19 challenges have stretched the
project and instrument teams as they find ways to meet deadlines when parts
are delayed or staffing is short. Engineers, technicians, and scientists
continue to power through.
“What we’ve seen, even in the midst of the pandemic, is that the engineering
and instrument teams are responding very well. The pandemic has affected
mission schedule, but the teams are tackling the challenges, communicating
openly, and displaying tremendous flexibility to keep the hardware on track
for our October 2024 launch,” said Europa Clipper Deputy Project Manager
Jordan Evans. “We see it day in and day out, across the team, and it’s
fantastic.”