September 11, 2024<\/p>\n
4 min read<\/p>\n<\/div>\n
Europa Clipper, NASA\u2019s Mission to Jupiter\u2019s Oceanic Moon, Is \u2018Go\u2019 for Launch<\/p>\n
The Europa Clipper spacecraft is only weeks away from lifting off on an epic voyage to one of the solar system\u2019s most enigmatic and enticing moons<\/p>\n<\/div>\n
By Michael Greshko<\/a> & Nature magazine<\/a><\/p>\n Technicians prepare to install Europa Clipper\u2019s 3-meter-wide antenna on the spacecraft on 17 June at the Kennedy Space Center in Cape Canaveral, Florida.<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/div>\n After decades of dreaming of Jupiter\u2019s moon Europa \u2014 and the vast ocean that probably lies beneath its icy surface \u2014 scientists are now weeks away from sending a spacecraft there. NASA confirmed yesterday that its Europa Clipper mission will launch on schedule, following a scare that it might have to be significantly delayed owing to possibly faulty transistors installed on the US$5-billion spacecraft.<\/p>\n \u201cWe are confident that our beautiful spacecraft and capable team are ready for launch operations and our full science mission at Europa,\u201d Laurie Leshin, the director of NASA\u2019s Jet Propulsion Laboratory (JPL) in Pasadena, California, said at a 9 September press conference.<\/p>\n With a mass of more than 3.2 tonnes, a height of roughly 5 metres, and a width of more than 30 metres with its solar panels fully unfurled, Europa Clipper is the largest spacecraft that NASA has ever built for a planetary mission. Yesterday, the mission passed what\u2019s known in NASA parlance as \u2018key decision point E\u2019 \u2014 the final review hurdle that needs to be cleared before proceeding towards launch. The spacecraft\u2019s launch window opens on 10 October.<\/p>\n If you’re enjoying this article, consider supporting our award-winning journalism by subscribing<\/a>. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.<\/p>\n If it takes off successfully next month, the orbiter will arrive at Jupiter in April 2030. Its nine instruments will then investigate both Europa\u2019s icy crust and the ocean that scientists suspect lies beneath it, to determine whether the moon could support life as we know it. Previous missions have suggested that Europa\u2019s icy surface hides a subterranean ocean of brine with more than twice the volume of water in Earth\u2019s oceans. The moon\u2019s fissured, seemingly young surface also implies that the satellite has active geology \u2014 hinting that Europa\u2019s interior could be warm and dynamic enough for the complex chemistry of life.<\/p>\n There\u2019s no such thing as a tricorder \u2014 a fictional instrument from the Star Trek universe \u2014 that we can aim at something to reveal whether it is alive, said Curt Niebur, the Europa Clipper programme scientist at NASA\u2019s headquarters in Washington DC, during the press conference. \u201cIt is extremely difficult to be able to detect life, especially from orbit,\u201d he said. \u201cFirst, we\u2019re going to ask the straightforward question: Are the proper ingredients there for life to exist?\u201d<\/p>\n Before the transistor scare, Europa Clipper had endured its share of setbacks. In 2019, NASA angered scientists by cutting a sophisticated magnetometer from the spacecraft<\/a>, citing budget concerns. The mission also endured uncertainty for years over how it would get to space. That\u2019s because the US Congress had long mandated that the spacecraft fly aboard NASA\u2019s long-delayed Space Launch System rocket. Finally, in 2020, US lawmakers allowed the programme to select the reliable Falcon Heavy rocket from private firm SpaceX in Brownsville, Texas, for the launch.<\/p>\n The possible transistor problem reared its head in May this year<\/a> when NASA engineers learnt that batches of a certain kind of transistor already installed on the Europa Clipper spacecraft were misbehaving. The components, called MOSFETS (metal-oxide-semiconductor field-effect transistors), act like switches in electrical circuits. They came from a NASA supplier, the company Infineon, based in Neubiberg, Germany.<\/p>\n Because Europa Clipper is set to fly past Europa 49 times, at distances as close as 25 kilometres, the spacecraft will also need to fly through a fusillade of charged particles accelerated by Jupiter\u2019s magnetic field, which is roughly 20,000 times as strong as Earth\u2019s. This means that the electronics housed in the orbiter must resist radiation damage.<\/p>\n But in May NASA said it was examining whether the mission\u2019s transistors risked malfunctioning. The agency launched into four months of 24-hour intensive testing at three different facilities: JPL; the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland; and the NASA Goddard Space Flight Center in Greenbelt, Maryland. \u201cThis was a huge lift, and I think \u2018huge lift\u2019 is a huge understatement,\u201d Leshin said.<\/p>\n After evaluating spare MOSFETs from the same batches that were installed on Europa Clipper, NASA found that the spacecraft\u2019s circuits would perform as expected. This conclusion partially rests on the fact that during the first half of its four-year baseline mission orbiting Jupiter, the spacecraft will be in the worst of Jupiter\u2019s radiation only one out of every 21 days. The rest of the time, the orbiter\u2019s transistors can partially self-heal from radiation damage when gently heated, via a process called annealing.<\/p>\n \u201cWhile Europa Clipper does dip into the radiation environment, once it comes out, it comes out long enough for those transistors the opportunity to heal and partially recover between flybys,\u201d said Jordan Evans, the Europa Clipper project manager at JPL during the conference. \u201cWe can \u2014 I have high confidence, and the data bears it out \u2014 complete the original mission.\u201d<\/p>\n This article is reproduced with permission and was <\/i>first published<\/i><\/a> on September 10, 2024<\/i>.<\/p>\n<\/div>\n![\"Technicians](\"https:\/\/static.scientificamerican.com\/dam\/m\/3fef5921caf2ef4e\/original\/Technicians_in_blue_suits_and_white_caps_installing_antenna_on_spacecraft.jpg?w=600\")
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Choppy waters en route to an ocean world<\/h2>\n