In a few mission expansions, NASA paved the way for more seismic observations on Mars with the robot InSight lander and approved plans for the Juno spacecraft to change its orbit and close flies from Jupiter’s icy moon Europa, Ganymede and the to perform volcanic moon. Io.
The Juno mission, which has been in orbit around Jupiter since July 4, 2016, has been approved for an extension of four years to September 2025, assuming the spacecraft continues to operate. NASA also granted a two-year extension for the InSight mission, which landed on Mars on November 26, 2018.
The Juno orbit focused on observations of Jupiter in the first four years on the giant planet, but the mission’s to-do list will grow in the coming years to include flybys and measurements of Jupiter rings and three of its largest moons. close.
Led by NASA’s Jet Propulsion Laboratory, the InSight mission has been extended by two years until December 2022. InSight will continue to measure seismic tremors on Mars and produce data to help scientists unravel the internal structure of the Red Planet. .
The solar-powered Mars lander will also continue to operate a weather station, and ground crews will make plans to bury a tedder leading to InSight’s seismometer in hopes of eliminating the instrument’s data outage. .
A lower priority for the InSight team during the two-year mission is to continue with the lander’s robotic arm to hammer a heat probe deeper into the Martian soil. The mole – one of InSight’s two main instruments along the seismometer – got stuck in early 2019 before reaching a planned depth of at least 3 meters to measure the heat gradient in the Red Planet.
Despite the problem with the heat probe, InSight’s seismic sensors worked as designed. The seismometer instrument made the first detection of a ‘marching earthquake’ shortly after it was put into service on the planet’s surface in 2019.
The Juno spacecraft examined the atmosphere and internal structure of Jupiter, revealing new insights into Jupiter’s cyclonic storms and finding evidence for a large, possibly dissolved nucleus at its center.
Scott Bolton, Juno’s lead researcher at the Southwest Research Institute in San Antonio, said last year that the spacecraft could address a wider range of scientific questions if NASA provided an extended mission.
“It’s really becoming a complete systems explorer, not as focused as the main mission was,” Bolton said last year. “We have several aircraft from Io, Europa and Ganymede.”
The solar-powered Juno spacecraft was launched in August 2011 and begins a five-year voyage to Jupiter.
Juno’s nine scientific instruments include a microwave radiometer for atmospheric zones, ultraviolet and infrared spectrometers, particle detectors, a magnetometer and a radio and plasma wave experiment. The Jupiter orbit also carries a color camera known as the JunoCam, which collects image data for processing and analysis by an army of civil scientists around the world.
NASA has approved the additions for the InSight and Juno missions following recommendations from a senior review team, where a panel of independent scientists will assess the merits of NASA’s robotic science missions beyond their original planned lifespan.
In considering senior recommendations, NASA balances the scientific productivity of older missions with priorities for developing and launching new spacecraft. By 2020, InSight and Juno were ready for expansion after reaching their primary mission phases.
“The senior review confirmed that these two planetary science missions are likely to continue to bring new discoveries and raise new questions about our solar system,” said Lori Glaze, director of the planetary science division at NASA headquarters in Washington. “I thank the members of the senior judging panel for their comprehensive analysis and also thank the mission teams who will now provide exciting opportunities to refine our understanding of the dynamic science of Jupiter and Mars.”
Juno’s primary mission cost about $ 1.1 billion, while InSight developed for about $ 1 billion, launched and flew to Mars, including contributions from European partners. The cost per year for operating each mission is significantly lower than the development cost and launch of the spacecraft.
The senior reviewers found that InSight and Juno ‘produced exceptional science’ and recommended that both missions be expanded. NASA approved the expansions Friday.
Lockheed Martin built the InSight and Juno spacecraft for NASA.
While the expansion of InSight is largely about improving and expanding datasets from the country’s main mission, Juno will aim for new targets over the next four years.
The flies of Jupiter’s moons are powered by Juno’s changing orbit. Jupiter’s asymmetric gravitational field gradually disrupts Juno’s trajectory and, according to Bolton, draws the nearest point of the spacecraft’s elliptical or egg-shaped, 53-day orbit northward.
The northward migration of Juno’s period, or the closest approach to Jupiter, will allow the spacecraft to take a closer look at the planet’s north pole. Juno was the first mission to see a glimpse of Jupiter’s poles, and now the spacecraft could see the North Pole and its cyclonic storms in more detail.
“It gives us the proximity to the northern parts of Jupiter, which is a new frontier,” Bolton said. “We saw a lot of activity there, so we will be able to explore it up close, while in the primary mission we were limited to the lower latitudes.”
In an extended mission, the spacecraft will also be able to quantify how much water is trapped inside Jupiter’s atmosphere, Bolton said.
Juno’s naturally evolving orbit is also what will make the spacecraft go near Jupiter’s moons and rings.
The lunar planes could begin in mid-2021 with an encounter with Ganymede, Jupiter’s largest moon, at a distance of about 1,000 kilometers, Bolton said last year.
After a series of distant passes, Juno will travel just 320 kilometers above Europe in late 2022 for a fast-moving flight. Only NASA’s spacecraft Galileo, which ended its mission in 2003, came closer to Europe.
There are two encounters with Jupiter’s volcanic moon Io planned in 2024 at distances of about 1,500 kilometers (1,500 kilometers), according to the flight plan Bolton presented last year. Juno will be able to search for changes on the surfaces of Jupiter’s moons, as it was last seen near NASA’s Voyager and Galileo probes.
In Ganymede, Juno will map the moon’s surface composition and investigate the 3D structure of Ganymede’s magnetosphere. Ganymede is the only moon in the solar system that has its own magnetic field.
Juno’s microwave radiometer can examine the thickness of Europe’s global ice shell, which covers an ocean of liquid water. “We’ll see where the ice is thin and where it’s thick,” Bolton said.
Juno’s spectrometers will also map concentrations of water ice, carbon dioxide and organic molecules on 40 percent of Europe’s surface, Bolton said.
“Image observations will find changes since Voyager and Galileo, and observations with the spacecraft’s microwave radiometer will explore Europe’s ice shell,” NASA said. “In situ measurements of Jupiter’s ring system will examine their structure and characterize their dust population.”
The visit to Europe will give scientists a taste of what will happen to NASA’s Europe Clipper mission, which could start as early as 2024. Europa Clipper will carry a more powerful radar – including instruments – around the moon’s ice shell through a series of targeted fly bees.
The JunoCam imager will take the sharpest photos of Europe since the Galileo mission’s last encounter with the icy moon in 2000, enabling scientists to search for evidence of plumes erupting from the surface of Europe.
The other instruments of the spacecraft will be set up to search for particles caged from Europe in the possible plumes. Signs of recurring eruptions from Europe were detected by the Hubble Space Telescope.
During its flight planes, Juno will search with Io for evidence of a global magma ocean feeding Io’s volcanoes. Juno can also observe active volcanoes in the polar regions of Io.
Juno is the second spacecraft orbiting Jupiter after the Galileo mission, which deliberately crashed on the giant planet in 2003. Galileo’s last nearby flight of one of Jupiter’s moons, Io, took place in 2002.
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