This picture of Mars is a composite of several images
captured by Europa Clipper’s thermal imager on March 1. Bright regions are
relatively warm, with temperatures of about 32 degrees Fahrenheit (0 degrees
Celsius). Darker areas are colder. The darkest region at the top is the
northern polar cap and is about minus 190 F (minus 125 C).
NASA/JPL-Caltech/ASU
Headed for Jupiter’s moon Europa, the spacecraft did some sightseeing,
using a flyby of Mars to calibrate its infrared imaging instrument.
On its recent swing by Mars, NASA’s
Europa Clipper took the opportunity to capture infrared images of the Red
Planet. The data will help mission scientists calibrate the spacecraft’s
thermal imaging instrument so they can be sure it’s operating correctly when
Europa Clipper arrives at the Jupiter system in 2030.
The mission’s sights are set on
Jupiter’s moon Europa and the global ocean hidden under its icy surface. A year
after slipping into orbit around Jupiter, Europa
Clipper will
begin a series of 49 close flybys of the moon to investigate whether it holds
conditions suitable for life.
A key element of that investigation
will be thermal imaging — global scans of Europa that map temperatures to shed
light on how active the surface is. Infrared imaging will reveal how much heat
is being emitted from the moon; warmer areas of the ice give off more energy
and indicate recent activity.
The imaging also will tell
scientists where the ocean is closest to the surface. Europa is crisscrossed by
dramatic ridges and fractures, which scientists believe are caused by ocean
convection pulling apart the icy crust and water rising up to fill the gaps.
This picture of Mars is a colorized composite of
several images captured by Europa Clipper’s thermal imager. Warm colors
represent relatively warm temperatures; red areas are about 32 degrees
Fahrenheit (0 degrees Celsius), and purple regions are about minus 190 F (minus
125 C).
NASA/JPL-Caltech/ASU
“We want to measure the temperature of those features,” said Arizona State
University’s Phil Christensen, principal investigator of Europa Clipper’s infrared camera, called the Europa Thermal Imaging System
(E-THEMIS). “If Europa is a really active place, those fractures will be warmer than
the surrounding ice where the ocean comes close to the surface. Or if water
erupted onto the surface hundreds to thousands of years ago, then those
surfaces could still be relatively warm.”
Why Mars
On March 1, Europa Clipper flew
just 550 miles (884 kilometers) above the surface of Mars in order to use the
planet’s gravitational pull to reshape the spacecraft’s trajectory. Ultimately, the assist will get the mission to
Jupiter faster than if it made a beeline for the gas giant, but the flyby also
offered a critical opportunity for Europa Clipper to test E-THEMIS.
For about 18 minutes on March 1,
the instrument captured one image per second, yielding more than a thousand
grayscale pictures that were transmitted to Earth starting on May 5. After
compiling these images into a global snapshot of Mars, scientists applied
color, using hues with familiar associations: Warm areas are depicted in red,
while colder areas are shown as blue.
By comparing E-THEMIS images with
those made from established Mars data, scientists can judge how well the
instrument is working.
“We wanted no surprises in these
new images,” Christensen said. “The goal was to capture imagery of a planetary
body we know extraordinarily well and make sure the dataset looks exactly the
way it should, based on 20 years of instruments documenting Mars.”
NASA’s Mars
Odyssey orbiter,
launched in 2001, carries a sister instrument named THEMIS that has been
capturing its own thermal images of the Red Planet for decades. To be extra
thorough, the Odyssey team collected thermal images of Mars before, during, and
after Europa Clipper’s flyby so that Europa scientists can compare the visuals
as an additional gauge of how well E-THEMIS is calibrated.
Europa Clipper also took advantage
of the close proximity to Mars to test all the components of its radar
instrument in unison for the first time. The radar antennas and the wavelengths
they produce are so long that it wasn’t possible for engineers to can do that
in a clean room before launch. The radar data will be returned and analyzed in
the coming weeks and months, but preliminary assessments of the real-time
telemetry indicate that the test went well.
To leverage the flyby even further,
the science team took the opportunity to ensure that the spacecraft’s
telecommunication equipment will be able to conduct gravity experiments at Europa. By transmitting signals to Earth while passing through
Mars’ gravity field, they were able to confirm that a similar operation is
expected to work at Europa.
Europa Clipper launched from NASA’s Kennedy Space Center in Florida on Oct. 14, 2024, via a
SpaceX Falcon Heavy, embarking on a 1.8 billion-mile (2.9 billion-kilometer)
journey to Jupiter, which is five times farther from the Sun than Earth is. Now
that the probe has harnessed the gravity of Mars, its next gravity assist will
be from Earth in 2026.
More About Europa Clipper
Europa Clipper’s three main science
objectives are to determine the thickness of the moon’s icy shell and its
interactions with the ocean below, to investigate its composition, and to
characterize its geology. The mission’s detailed exploration of Europa will
help scientists better understand the astrobiological potential for habitable
worlds beyond our planet.
Managed by Caltech in Pasadena,
California, NASA’s Jet Propulsion Laboratory in Southern California leads 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. APL designed the main spacecraft body in
collaboration with JPL and NASA’s Goddard Space Flight Center in Greenbelt,
Maryland, NASA’s Marshall Space Flight Center in Huntsville, Alabama, and
Langley Research Center in Hampton, Virginia. The Planetary Missions Program
Office at NASA Marshall executes program management of the Europa Clipper
mission. NASA’s Launch Services Program, based at NASA Kennedy, managed the
launch service for the Europa Clipper spacecraft.
Find more information about Europa
Clipper here:
https://science.nasa.gov/mission/europa-clipper/
Source: NASA’s Europa Clipper Captures Mars in Infrared - NASA
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