Planetary scientists are discovering more about Jupiter’s fourth-largest moon, one of Earth’s nearest ocean worlds—places like Saturn’s moons Titan and Enceladus that have bodies of salty water and other liquids that could be amenable to the emergence of life. They’re presenting new findings this week about Europa’s cracked surface, hidden ocean, and geological activity at the biggest annual planetary conference in the United States, organized by the American Astronomical Society, held virtually for the second year in a row. The research serves as a prelude to tantalizing opportunities for new observations by upcoming missions being dispatched by NASA and the European Space Agency.“Europa is fantastic. Of anywhere in the solar system, outside the Earth, it has the greatest potential, I think, for maintaining a habitable environment that could support microbial life,” says Michael Bland, a US Geological Survey space scientist in Flagstaff, Arizona. After modeling the moon’s dynamic, rocky interior, Bland believes the conditions on its deep seafloor could be amenable to life, according to new work that he and NASA Jet Propulsion Laboratory scientist Catherine Elder presented at the conference on Monday.
After that, Bland, Babcock, and their colleagues look forward to NASA’s Europa Clipper, a mission years in the making that’s planned for launch in 2024. “The Europa Clipper will assess Europa’s habitability and how we might be able to use these investigations for other ocean worlds, thinking about the potential for life there as well,” says Kathleen Craft, a planetary scientist at Johns Hopkins University Applied Physics Laboratory in Baltimore, who will be presenting at the conference on Thursday.The car-sized orbiter, with 100-foot solar panels unfurled on each side, will use radar, radio signals, and gravity science to study the structure of the moon, including measuring the thickness of the ice shell and the depth of the underground ocean. It will also try to snag samples from its plumes, which could include droplets from the ocean itself that might reveal information about how conducive to life it really is, Craft says. A baguette-sized instrument will ingest gas and vapor, analyze and classify the contents, and then beam the crucial data back to scientists at home.Its mission also includes conducting aerial surveillance for a potential lander mission to Europa, which could scoop up material on the surface, or drill down for it, looking for that coveted evidence of extraterrestrial lifeforms.
Arizona State University (ASU) scientists and engineers building the Europa Thermal Emission Imaging System (E-THEMIS) for NASA's Europa Clipper passed a major hurdle recently by capturing the first successful test images from this complex infrared camera, known as "first light" images.
Two interesting updates on Clipper plans from today's OPAG meeting.1) There will be no Jupiter system science. The last Decadal Survey said that to constrain costs on a reformulated Europa mission (which eventually became Clipper) that the system science should be dropped. The current mission plan does that.2) The only measurements at Ganymede and Callisto will be to calibrate the instruments, not to conduct science observations (although useful science might come out of the calibration measurements).While this may seem disappointing, the JUICE mission is designed to do extensive Jovian system science and to conduct science campaigns at Ganymede and Callisto.
[snip]Lastly, I just saw this now and figured I'd post it as well - it's a report on the engineers refining the flyby trajectories:https://europa.nasa.gov/news/38/mission-dispatch-tweaking-the-trajectory/
While looking at the slides of last year's August 2021 OPAG meeting presentations, I see that the Europe Clipper slides have impressive photos of the payload instruments and their placements on the probe. Looking at the "Payload accommodation" slide 9, I wondered who has the final say on placing these instruments? Presumably, just guessing, they must be distributed for a good centre of gravity of the probe and easy handling, but the science requirements might dictate another placement. If that guess is correct then who would actually balance out the probe? APL?
JPL is responsible for the total design and has to trade payload vs spacecraft requirements.
I heard something last year while working on the planetary decadal survey and I cannot remember the specifics, but there's actually a set of guidelines about who can ultimately trade off payload--and science--for spacecraft requirements. In other words, NASA has specific rules that say that "Person X can decide that some science cannot be done and remove that from the mission in order to accomplish other mission goals." They get the last word, although they will have to justify those decisions to the associate administrator.[...] NASA has put in place rules that give certain people the power to do that [downgrade science to get mission to work]. They have to. It's necessary when managing complex programs. I'm sure JWST operated under similar rules.
If you have a fixed budget, or a fixed launch date, then there may be no alternative to dropping science. Planetary missions have both constraints, so it's doubly necessary.
Presuming 'Clipper holds up well, how much might an extension cost, and could it have the flexibility to investigate Jupiter and the other moons?
So any non-Europa science would have to wait until a mission extension, right?
Quote from: Jim on 01/31/2022 06:56 pmJPL is responsible for the total design and has to trade payload vs spacecraft requirements.I heard something last year while working on the planetary decadal survey and I cannot remember the specifics, but there's actually a set of guidelines about who can ultimately trade off payload--and science--for spacecraft requirements. In other words, NASA has specific rules that say that "Person X can decide that some science cannot be done and remove that from the mission in order to accomplish other mission goals." They get the last word, although they will have to justify those decisions to the associate administrator.The context of that is important, because the scientific community has established high-level science goals for the mission, and then through a series of steps, turned those into specific science goals for the mission. And they become very attached to those goals and mad if they are not going to be achieved. But somebody actually has to make the mission work, and it is possible that something like a fuel or mass margin requires losing some of the science (not always deleting a payload, but maybe not performing observations or not allocating comm to a payload). I think that this discussion came up because of the magnetometer issue, when JPL had to accept much lower science, and members of the community were really upset and asked how they could do that, because the science requirements were clear. NASA has put in place rules that give certain people the power to do that. They have to. It's necessary when managing complex programs. I'm sure JWST operated under similar rules.
One unusual issue that Clipper faces is that ESA is flying a mission with a similar instrument payload which will be operating at Jupiter at the same time. Clipper arrives 16 months before JUICE so it could theoretically take some discoveries away from the Europeans before they arrive. This would lead to questions from the press about duplication and waste. Focusing Clipper entirely on Europa and leaving Ganymede and the rest of the system to Europe is both a sensible division of effort and good politics.
Quote from: Blackstar on 01/31/2022 08:08 pmQuote from: Jim on 01/31/2022 06:56 pmJPL is responsible for the total design and has to trade payload vs spacecraft requirements.I heard something last year while working on the planetary decadal survey and I cannot remember the specifics, but there's actually a set of guidelines about who can ultimately trade off payload--and science--for spacecraft requirements. In other words, NASA has specific rules that say that "Person X can decide that some science cannot be done and remove that from the mission in order to accomplish other mission goals." They get the last word, although they will have to justify those decisions to the associate administrator.The context of that is important, because the scientific community has established high-level science goals for the mission, and then through a series of steps, turned those into specific science goals for the mission. And they become very attached to those goals and mad if they are not going to be achieved. But somebody actually has to make the mission work, and it is possible that something like a fuel or mass margin requires losing some of the science (not always deleting a payload, but maybe not performing observations or not allocating comm to a payload). I think that this discussion came up because of the magnetometer issue, when JPL had to accept much lower science, and members of the community were really upset and asked how they could do that, because the science requirements were clear. NASA has put in place rules that give certain people the power to do that. They have to. It's necessary when managing complex programs. I'm sure JWST operated under similar rules. I was thinking about this a bit more and a bit more of my memory came back. The issue was over who "owns" the science requirements for a science mission. And the answer that came back from NASA was that in the end, it is the program manager (who is an engineer and not a scientist) who "owns" those requirements and can trade them off for other factors, like mission success, margins (safety, fuel, mass), etc.When you dig really far down into Europa Clipper, you can find some scientists who are not happy with the quality of the science that the mission will do. They wanted something that would achieve X, Y, and Z, and what they're getting is something that will achieve X-1, Y-1, and Z-1 instead. But that's not true for all of the scientists, and some of them may be unhappy that they are not getting everything they want, but happy that they are getting something. It's a matter of how much some people complain, because just about everybody can complain.I think that this issue of "ownership" of the science requirements also came up with Perseverance with landing site selection, and you can probably find mention of that in the Perseverance threads. There the issue was who had the final say in where the rover landed, and it really rested with the person who ran the mission based on engineering considerations. And if you take a broad enough perspective, and look at historical examples, you will find that this kind of stuff happened throughout the planetary space program. An example was the tradeoffs for a moveable instrument platform on Cassini vs. fixed instruments that required the spacecraft to turn and point for observations and limited simultaneous observations. The scientists wanted a moveable instrument platform. But at some point, somebody had to make a call on that, and they calculated that eliminating the platform would save a lot of money and that was more important to the program. In the end, somebody has to be authorized to make the tough calls on mission design.
All that said, I personally won't be surprised if NASA doesn't end up budgeting some money to collect other system data, sort of an extended mission during the actual prime mission. But that is my pure speculation.
If they’re having trouble doing that — and the science community cares — the AA can pull on levers like budget reserves, risk posture, and plain old schedule slips to fix
I think that most major programs divide up their reserves and the program manager has some reserves, but the AA also has some reserves. So the program manager is required to fix their problems using their own reserves, but if they have to, they can appeal to the AA for some of their reserves. That's not something they do lightly, because it's the equivalent to going to the boss for more money.
