In the two mission extensions, the National Aeronautics and Space Administration (NASA) used the InSight lander to clear the way for more seismic observations on Mars, and approved the Juno spacecraft to change its orbit and execute the Jupiter Ice Moon Europa , Ganymede and the volcanic moon flyover plan o
Since July 4, 2016, the Juneau mission, which is operating near Jupiter, has been approved for a four-year extension until September 2025, provided that the spacecraft is still in operation. NASA also extended the InSight mission for two years, which landed on Mars on November 26, 2018.
The Juno orbiter has focused on Jupiter observations for the first four years on the giant planet, but the mission’s list of tasks will increase in the next few years, including flybys and measurements of Jupiter’s rings and its three largest moons.
The InSight mission, led by NASA’s Jet Propulsion Laboratory, has been extended for two years and will last until December 2022. InSight will continue to measure the seismic tremors of Mars and provide data to help scientists unravel the internal structure of the Red Planet.
The solar-powered Mars lander will also continue to operate the weather station, and the ground team will make plans to bury the ropes leading to the InSight seismograph in order to eliminate data loss in the instrument.
In the two-year mission, the InSight team’s lower priority is to continue to work hard to use the lander’s robotic arms to help the thermal probe hammer itself deep into the Martian soil. The mole mouse, one of the two main instruments of the InSight seismograph, stalled in early 2019 until it reached the planned depth of at least 10 feet (3 meters) to measure the thermal gradient inside the Red Planet.
Despite the problems with the thermal probe, InSight’s seismic sensors still work as designed. An “earthquake” was detected for the first time soon after the seismograph was deployed on the earth’s surface in 2019.
The Juno spacecraft probed Jupiter’s atmosphere and internal structure, revealing new insights about Jupiter’s cyclone storms, and found evidence of a large nucleus that may dissolve in its center.
Juno’s principal investigator at the Southwest Research Institute in San Antonio, Scott Bolton, said last year that if NASA approves the mission extension, the spacecraft could solve a wider range of scientific problems.
Bolton said last year: “It has indeed become a complete system browser, not as focused as the main task.” “We have multiple flybys of Io, Europa and Ganymede.”
The solar-powered Juno spacecraft was launched in August 2011 and began a five-year voyage to Jupiter.
Juno’s nine scientific instruments include microwave radiometers for atmospheric detection, ultraviolet and infrared spectrometers, particle detectors, magnetometers, and radio wave and plasma wave experiments. The Jupiter orbiter is also equipped with a color camera called JunoCam, which collects image data for processing and analysis by an army of citizen scientists around the world.
After the recommendations of the high-level review, NASA approved the extension of the InSight and Juno missions, and the independent expert team assessed that the extension of the InSight and Juno missions exceeded its original planned useful life.
When considering the recommendations of the advanced review, NASA will balance the scientific productivity of the old mission with the priorities of developing and launching new spacecraft. In 2020, InSight and Juno expanded after reaching the end of the main mission phase.
“The advanced review has confirmed that these two planetary science missions may continue to bring new discoveries and new problems to our solar system,” said Lori Glaze, director of the planetary science department at NASA headquarters in Washington. )Say. “I thank the members of the senior review team for their comprehensive analysis and the mission team, who will now continue to provide exciting opportunities to deepen our understanding of the dynamics of Jupiter and Mars.”
Juno’s main mission cost approximately US$1.1 billion, and the development, launch and flight of InSight to Mars at a price of approximately US$1 billion, including donations from European partners. The cost of performing each mission every year is much lower than the cost of developing and launching a spacecraft.
The senior review panel members found that InSight and Juno “produced outstanding science” and recommended extending these two tasks. NASA approved the expansion on Friday.
Lockheed Martin built the InSight and Juno spacecraft for NASA.
InSight’s expansion is mainly to improve and expand the data set for the main mission of the lander, and Juno will target new targets in the next four years.
Juno’s changing orbit will make the overflight of Jupiter’s moons possible. According to Bolton, Jupiter’s asymmetric gravitational field gradually disturbs Juno’s trajectory and, over time, pulls the spacecraft’s elliptical or oval 53-day orbit to the nearest point.
The way Juno’s lurkers migrate north, or the closest approach to Jupiter, will allow spacecraft to observe the North Pole of the Earth more closely. Juno is the first mission to discover the poles of Jupiter, and now spacecraft can see the North Pole and its cyclone storms in more detail.
Bolton said: “This brings us to the north of Jupiter, which is a new boundary.” “We saw a lot of activity there, so we can explore very closely, and in the main mission, we are limited to low latitudes. “
Bolton said that during the extended mission, the spacecraft will also be able to quantify how much water has accumulated in Jupiter’s atmosphere.
Juno’s natural evolutionary orbit will also allow the spacecraft to pass near Jupiter’s moons and rings.
Bolton said last year that the orbiting the moon may begin in mid-2021 when it will meet Jupiter’s largest moon, Ganymede, at a distance of about 600 miles (1,000 kilometers).
After a series of distant passes, Juno will dive 200 miles (320 kilometers) above Europa in late 2022 for a high-speed flyover. Only when NASA’s Galileo spacecraft ended its mission in 2003 could it be closer to Europa.
According to the flight plan proposed by Bolton last year, it plans to make two contacts with Jupiter’s volcano Io in 2024, with a flight distance of approximately 900 miles (1,500 kilometers). Since NASA’s Voyager and Galileo probes recently discovered Jupiter’s moons, Juno has been able to look for changes in the surface of Jupiter’s moons.
In Ganymede, Juno will map the surface composition of the moon and study the 3D structure of Ganymede’s magnetosphere. Ganymede is the only satellite in the solar system with its own magnetic field.
Juno’s microwave radiometer will be able to detect the thickness of Europa’s global ice crust, which covers an ocean of liquid water. Bolton said: “We will see places with thin ice and places with thick ice.”
Bolton said Juno’s spectrometer will also map the concentration of water ice, carbon dioxide and organic molecules on 40% of Europa’s surface.
NASA said: “Image observations will look for changes since Voyager and Galileo, and spacecraft’s microwave radiometer observations will explore the ice crust of Europa.” “In-situ measurements of Jupiter’s ring system will explore its structure and characterize it. Its dust population.”
The visit to Europa will give scientists a preliminary understanding of the implementation of NASA’s Europa Clipper mission (which will be launched in 2024). The Europa Clipper will be equipped with more powerful radars and other instruments to make targeted flyovers through a series of measurements of the moon’s ice crust.
Since the Galileo mission’s last encounter with the icy moon in 2000, the JunoCam imager will take the clearest picture of Europa, allowing scientists to search for evidence of plumes erupting from the surface of Europa.
Other instruments of the spacecraft will be adjusted to look for particles emitted from Europa in the possible plume. The Hubble Space Telescope found signs of repeated Europa eruptions.
During the flyby with Io, Juno will look for evidence that the global magma ocean feeds the Io volcano. Juno may also be able to observe the active volcanoes in the Io polar regions.
Juno has entered Jupiter’s orbit for the second time after the Galileo mission, which deliberately crashed into a giant planet in 2003. Galileo’s last flight over one of Jupiter’s moons (Io) took place in 2002.
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