NASA decided in October 2024 to launch the million-dollar Europe Clipper mission on a commercial heavy-lift rocket, and not on the space launch system, officials said Wednesday.
The decision puts an end to a long-running dilemma for NASA, which until last year was legally necessary to launch the Europe Clipper mission on the more expensive Space Launch system. The language conveyed in previous NASA grant bills prompted NASA to launch the probe on the SLS rocket, but Congress conceded in the 2021 fiscal year issued in December.
Legislators gave NASA some flexibility on the decision to launch the vehicle in fiscal year 2021, and ordered the agency to launch Europa Clipper on the Space Launch System only if the rocket is available, and as “if the torque-loading” analysis has confirmed that Clipper is suitable for SLS. ”
Europa Clipper executives last year expressed concern about the compatibility of the spacecraft with the Space Launch System due to structural loads that the probe will experience during an SLS launch. NASA officials said last year that a Space Launch System rocket would only be available for the Europa Clipper launch in 2025 due to commitments to use SLS rockets on the agency’s Artemis lunar missions.
If Europe’s Clipper is forced to launch on an SLS rocket, NASA will likely have to store the spacecraft to wait for the launcher’s availability, NASA officials said. And an SLS launch, according to the space agency, would cost up to $ 1.5 billion more than launching the Europa Clipper on a commercial rocket.
The flexibility in the 2021 budget language has given NASA the green light to finally proceed with a commercial missile acquisition for Europa Clipper.
Bob Pappalardo, project scientist for Europe Clipper at the Jet Propulsion Laboratory, said on Wednesday that NASA executives on January 25 ordered the Clipper team to launch the spacecraft on a commercial rocket. Engineers were previously designing the spacecraft to launch on an SLS or a commercial booster, which resulted in extra work and extra costs, and delayed the critical design review of Europa Clipper, a milestone in which the design of the spacecraft was frozen.
“We now have clarity on the launch of the launch vehicle and the launch date,” Pappalardo said Wednesday at a meeting of NASA’s Outer Planets Assessment Group. ‘We got direction from the Planetary Missions Program Office at the end of January to a single road vehicle road. We received a memorandum stating that the project ‘must cease immediately to maintain SLS compatibility and proceed with a CLV, a commercial launcher.’ ‘
The launch of the Europa Clipper mission on the more powerful space launch system will give the spacecraft an extra eruption as it leaves Earth, enabling a direct trip to Jupiter with a transit time of about two and a half to three year.
With a commercial rocket, such as Falcon Heavy, from SpaceX, the spacecraft will have to use gravity maneuvers, or flybys, with Mars and Earth to gain enough speed to swing into the outer solar system. This will increase the travel time to five and a half years from launch to arrival at Jupiter.
The Europa Clipper mission has a planetary launch window in 2024 that opens on October 10 and closes on October 30, based on a trajectory calculated by NASA and that the launch is accepted on a commercial rocket. The spacecraft would leave Earth on a course on 28 February 2025 and then return to Earth for a second gravitational assist on 2 December 2026 and place Clipper on orbit to orbit Jupiter on 11 April 2030.
Backup launch windows are available for Europa Clipper in 2025 and 2026, arriving at Jupiter later in the 2030s.
The longer flight time to Jupiter will contribute to Europa Clipper’s operating budget, but the cost is more than offset by the savings from launching on a cheaper commercial rocket.
Jan Chodas, Europe Clipper’s project manager at JPL, said the decision to go with a commercial rocket definitely helps the team from the point of view that they do not have to walk many of the double paths with SLS and a CLV, so there are cost savings there. ”
She said there is also an “increase in efficiency” for the Europa Clipper team because scientists and engineers can continue without duplicating the work for the SLS and commercial launch alternatives. Chodas said the Launch Services program at NASA’s Kennedy Space Center in Florida would oversee the launch of the launcher, which would result in a rocket choice “in about a year.”
The Launch Services program will hold a ‘full and open competition to select the launch vehicle for Clipper,’ said Curt Niebur, NASA’s program scientist for missions to outer planets. “That competition begins.”
NASA released a request for information reports on January 26, seeking answers from commercial launch providers in the United States about their ability to launch Europe Clipper. The mission is in NASA’s flagship class of interplanetary probes, with a cost commitment of $ 4.25 billion.
Europe Clipper’s multimillion dollar cost has a requirement to launch the spacecraft on a reliable rocket. NASA said in its January 26 request for information that the launch provider selected for Europe Clipper must perform at least three successful flights of the same launch vehicle configuration proposed for Clipper before the mission begins in October 2024, with at least two consecutive successful launches.
The Europa Clipper spacecraft is expected to weigh more than 13,000 pounds, or at least 6,065 kg, with fuel loaded for travel to Jupiter.
The mass of the spacecraft, coupled with the requirement for a high-speed departure from Earth, means that SpaceX’s Falcon Heavy rocket is the only launch vehicle expected to be available in 2024, and is also currently in use, which is the Europe Clipper mission can accommodate. This probably assumes that SpaceX expands the Falcon Heavy’s first stage amplifiers, dedicating all of the rocket’s achievements to the launch, leaving no propulsion to repair the stages.
After orbiting Europe around Jupiter, Europa Clipper will drive at a rate to make about 45 flying planes with Europe, going as far as 25 kilometers from the icy moon. Equipped with large solar power plants to generate electricity, the spacecraft will take a slightly different path through Europe at each pass and eventually survey almost the entire moon with observations of its nine scientific instruments.
Europe is covered with a global ice shelf that contains an ocean of liquid water and provides an environment that can be habitable for life. Clipper’s instruments will take high resolution photographs and map the composition and topography of Europe’s ice shell. The probe will carry a radar to reflect radio waves from the interior of Europe to determine the thickness and deep structure of the ice sheets, and Clipper will look for evidence of eruptions of water coming through the cracks in the ice, which a window in the area can provide. of the liquid ocean below.
Pappalardo said the Europe Clipper mission completed its critical design review in December. The review board identified concerns about costs regarding the mission’s development and operational plans and the launch vehicle decision as key issues facing the Clipper team. But NASA’s decision to go along with a commercial rocket ultimately reduces concerns, Pappalardo said.
“The whole project is still making great technical progress despite the COVID-19 impact,” Pappalardo said.
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