This animation is an artist’s concept of Loki
Patera, a lava lake on Jupiter’s moon Io, made using data from the JunoCam
imager aboard NASA’s Juno spacecraft. With multiple islands in its interior,
Loki is a depression filled with magma and rimmed with molten lava. Credit:
NASA/JPL-Caltech/SwRI/MSSS
Imagery from the solar-powered
spacecraft provides close-ups of intriguing features on the hellish Jovian
moon.
Scientists on NASA’s Juno mission
to Jupiter have transformed data collected during two recent flybys of Io into
animations that highlight two of the Jovian moon’s most dramatic features: a
mountain and an almost glass-smooth lake of cooling lava. Other recent science
results from the solar-powered spacecraft include updates on Jupiter’s polar
cyclones and water abundance.
The new findings were announced
Wednesday, April 16, by Juno’s principal investigator Scott Bolton during a
news conference at the European Geophysical Union General Assembly in Vienna.
Juno made extremely close flybys of
Io in December 2023 and February 2024, getting within about 930 miles (1,500
kilometers) of the surface, obtaining the first close-up images of the moon’s
northern latitudes.
“Io is simply littered with volcanoes, and we caught a few of them in action,” said Bolton. “We also got some great close-ups and other data on a 200-kilometer-long (127-mile-long) lava lake called Loki Patera. There is amazing detail showing these crazy islands embedded in the middle of a potentially magma lake rimmed with hot lava. The specular reflection our instruments recorded of the lake suggests parts of Io’s surface are as smooth as glass, reminiscent of volcanically created obsidian glass on Earth.”
The JunoCam instrument on NASA’s Juno captured this
view of Jupiter’s moon Io — with the first-ever image of its south polar region
— during the spacecraft’s 60th flyby of Jupiter on April 9.
Image credit: NASA/JPL-Caltech/SwRI/MSSS. Image
processing: Gerald Eichstädt/Thomas Thomopoulos (CC BY).
Maps generated with data collected by Juno’s Microwave Radiometer (MWR) instrument reveal Io not only has a surface that is relatively smooth
compared to Jupiter’s other Galilean moons, but also has poles that are colder than middle latitudes.
Pole Position
During Juno’s extended mission, the spacecraft flies closer to the north pole of
Jupiter with each pass. This changing orientation allows the MWR instrument to
improve its resolution of Jupiter’s northern polar cyclones. The data allows multiwavelength comparisons of the
poles, revealing that not all polar cyclones are created equal.
“Perhaps most striking example of
this disparity can be found with the central cyclone at Jupiter’s north pole,”
said Steve Levin, Juno’s project scientist at NASA’s Jet Propulsion Laboratory
in Southern California. “It is clearly visible in both infrared and visible
light images, but its microwave signature is nowhere near as strong as other
nearby storms. This tells us that its subsurface structure must be very
different from these other cyclones. The MWR team continues to collect more and
better microwave data with every orbit, so we anticipate developing a more
detailed 3D map of these intriguing polar storms.”
Jovian Water
One of the mission’s primary science goals is to collect data that could help scientists better understand Jupiter’s water abundance. To do this, the Juno science team isn’t hunting for liquid water. Instead, they are looking to quantify the presence of oxygen and hydrogen molecules (the molecules that make up water) in Jupiter’s atmosphere. An accurate estimate is critical to piecing together the puzzle of our solar system’s formation.
Created using data collected by the JunoCam
imager aboard NASA’s Juno during flybys in December 2023 and February 2024,
this animation is an artist’s concept of a feature on the Jovian moon Io that
the mission science team nicknamed “Steeple Mountain.” Credit:
NASA/JPL-Caltech/SwRI/MSSS
Jupiter was likely the first planet
to form, and it contains most of the gas and dust that wasn’t incorporated into
the Sun. Water abundance also has important implications for the gas giant’s
meteorology (including how wind currents flow on Jupiter) and internal
structure.
In 1995, NASA’s Galileo probe
provided an early dataset on Jupiter’s water abundance during the spacecraft’s
57-minute descent into the Jovian atmosphere. But the data created more
questions than answers, indicating the gas giant’s atmosphere was unexpectedly
hot and — contrary to what computer models had indicated — bereft of water.
“The probe did amazing science, but
its data was so far afield from our models of Jupiter’s water abundance that we
considered whether the location it sampled could be an outlier. But before
Juno, we couldn’t confirm,” said Bolton. “Now, with recent results made with MWR data, we have nailed down that the water abundance near
Jupiter’s equator is roughly three to four times the solar abundance when
compared to hydrogen. This definitively demonstrates that the Galileo probe’s
entry site was an anomalously dry, desert-like region.”
The results support the belief that
the during formation of our solar system, water-ice material may have been the
source of the heavy element enrichment (chemical elements heavier than hydrogen
and helium that were accreted by Jupiter) during the gas giant’s formation
and/or evolution. The formation of Jupiter remains puzzling, because Juno
results on the core of the gas giant suggest a very low water abundance — a
mystery that scientists are still trying to sort out.
Data during the remainder of Juno’s
extended mission may help, both by enabling scientists to compare Jupiter’s
water abundance near the polar regions to the equatorial region and by shedding
additional light on the structure of the planet’s dilute core.
During Juno’s most recent flyby of
Io, on April 9, the spacecraft came within about 10,250 miles (16,500
kilometers) of the moon’s surface. It will execute its 61st flyby of Jupiter on
May 12.
More About the
Mission
NASA’s Jet Propulsion Laboratory, a
division of Caltech in Pasadena, California, manages the Juno mission for the
principal investigator, Scott Bolton, of the Southwest Research Institute in
San Antonio. Juno is part of NASA’s New Frontiers Program, which is managed at
NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s
Science Mission Directorate in Washington. The Italian Space Agency (ASI)
funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver
built and operates the spacecraft.
More information about Juno is available at: https://www.nasa.gov/juno
Source: NASA’s
Juno Gives Aerial Views of Mountain, Lava Lake on Io - NASA
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