"JPL led the U.S. into space with Explorer 1, the first U.S. satellite, and joined NASA shortly after the agency formed in 1958. JPL spacecraft have flown to every planet in the solar system, the Sun, and into interstellar space in a quest to better understand the origins of the universe, and of life."
Not many organizations can say that: We've flown to every planet in the solar system. Wow. (And of course, they've done more than that.)
The NASA+ stream died for me "404 The cosmic object you were looking for has disappeared beyond the event horizon." I much preferred the old IBM stream they used to use. Shame, but at least it sounds like the launch was a success.
Nothing nonchalant about it. There was a stringent qualification process.
The time between boosters first being reused in Falcons and this mission is the same as the time between JFK's 'we choose to go to the moon' speech and the actual moon landings.
I worked on one component of the spacecraft which was a derivative of something we've built may times before. However, the test program was entirely unique to Europa Clipper, and most of the cost was in this bespoke testing. The use of a "heritage" component served mostly to lower risk; it did not save much cost overall.
There’s also politics at play. Public space agencies need to keep the absolute number of failures down to keep funding flowing, even if it costs absurd amounts to do it due to rapidly diminishing returns. This is especially important to flagship missions.
When I took Ae105 at Caltech, the NASA MSL project manager explained it like this (I remember the numbers he used clearly): a mission might cost $500 million with an 80% chance of success, or they can spend twice as much to increase the chance of success to 95% by investing a lot more in upfront testing and R&D. Now, the smart thing to do - given a billion dollar budget - is to take that first option because if it fails you can try again and the probability of both attempts failing is only 4%, compared to 5% for the expensive single mission. Then you’ve got an 80% chance of having $500 million left over for a different mission.
The public and decision makers react irrationally to any failure, putting funding for other missions and the entire program in jeopardy. NASA and ESA have to make some extremely suboptimal decisions to make sure that funding doesn’t get catastrophically cut.
The above is the example the instructor used to easily illustrate his point but he said the real numbers are even more stark. Often times the cost savings of just building a second copy of the payload along with the first means it costs $600 million for the first attempt, and only $200 million for the second (the cost of the launch vehicle and keeping people on staff), saving hundreds of millions overall.
> The public and decision makers react irrationally to any failure, putting funding for other missions and the entire program in jeopardy. NASA and ESA have to make some extremely suboptimal decisions to make sure that funding doesn’t get catastrophically cut.
Which, incidentally, is one of the key reasons SpaceX has had the success they have: they're set up to handle failure and avoid this politics. How many Starships have blown up? If Starship were a NASA program, how many explosions ago would it have been cancelled? And yet this approach to risk is pretty effective!
Isn't that partly or largely due to Musk's influence? Like many powerful influencers, Musk can reliably rally supporters to even an unreality.
Compare the responses to a failure by Boeing or SLS and to a
failure by SpaceX.
Also, SpaceX hasn't had a serious non-experimental failure yet (?). I'm sure their PR is preparing for that eventuality, but when non-fans are upset over a bad outcome and then learn about the risk tolerated, they will swing from admiring risk to condemning it. Imagine the Congressional committees.
Even if SpaceX is super-conservative when flying humans (which we shouldn't assume - cultures tend to be consistent), if someone dies then all that risk-seeking behavior will be attacked.
(To be clear, as long as SpaceX can manage risk in production - i.e., with high-value payloads such as people and NASA flagships - I think they and everyone else should use risk efficiently.)
It's really frustrating that there's not a way to educate the public on simple concepts like this. You'd think the out-in-the-open development approach of SpaceX, for instance, would make it blatantly obvious how much money they're saving by permitting failure...yet the news continually spins their less-than-perfectly successful test launches as undesirable. And space spending is perhaps one of the least consequential areas of government where this failure of the herd to comprehend reality applies.
The public are smarter than you give them credit for. For the most part space missions are contests between governments and those governed with science as a consolation price. If you are part of team A do you want to have to come up with reasoning on why you lost? No. Does anyone care if a billionaire's toy gets blown up? No. The obvious choice to eliminate all risk would be not to play, but that is not an option; the other is to delay and delay some more. Thus, SLS.
And can introduce unusual failure cases for these bespoke missions. Mars Observer was lost in flight to Mars three decades ago, probably because of the inappropriate reuse of a satellite rocket engine. (1) The space environment out around Jupiter is really quite different from the environment that the JWST is facing around E-S L2 or what the Parker Solar Probe is facing right near the Sun. Even if the component is spec'd to handle the environment, you need to have actual educated humans (read: expensive labor) determine what those conditions will be, and then verify that the part will meet it, and that's where the money goes- to pay all of those humans.
If you built even 15 Europa Clippers the cost per-item would come down enormously (because all of those people's work could be re-used), but since the 1970's NASA has not had the budget for multiple probes per missions. So every mission is bespoke, and has to be done again completely from scratch.
1: The engine was normally used for circularizing the orbit of a geosynch comm satellite, so within a few hours of flight. For doing a Mars Insertion burn it needed to sit fueled for months in outer space, which was not appropriately tested, and probably the fuel tank exploded in flight because of that.
> So every mission is bespoke, and has to be done again completely from scratch.
Is there room here for making things more reusable? For example, instead of creating one big satellite with tens of instruments, how about they create 10 satellites with one instrument each? or would that still be too bespoke to lower the cost per item?
While we now live in an era of abundant rocket launches, it used to cost far more to launch with very few launches per year.
The whole strategies of exploration haven’t shifted yet to this new paradigm. Hopefully NASA starts making smaller probes and launching them far more often.
Europa Clipper is literally the largest thing ever launched to the outer planets (so big that Falcon Heavy can't be reused for this mission, they have to throw it all away in order to get every last jot of performance out of the rocket- so this is not an "abundant rocket launches" situation- this is a fully expendable rocket just like an Atlas V). And the size is not for fun, but because going close to Europa (the entire point of the mission) means going through the second strongest set of EM and radiation belts in our solar system. Even with this size- meaning it can have a lot more shielding than normal- the probe can only survive a few months of the radiation from Jupiter's van Allen belts. The plan is to break that few months of exposure up over about four years of calendar time, by having it do highly elliptical orbits so it stores a lot of data during a close flyby of Europa and then transmits that all back to Earth while it is far outside of Jupiter's radiation storm, then it can head back down and collect more data. And that lengthy transmission time is because it is sending information from so far away- and has so little juice that the effective bandwidth is tiny.
It is possible for a swarm of small satellites to fill niches in space exploration. Closely studying Europa isn't really one of them with today's technology.
Yeah. I'm surprised that we don't have a standard deep space probe bus by now in at least serial production, at least for orbiters if not landers, rovers, and such.
Each mission has unique requirements, but since payload mass costs are coming down, ISTM it should be possible to create a standard buss that meets most requirements most of the rime, even if it's heavier than a bespoke effort for any one mission.
For things in Earth orbit (LEO all the way up to GEO) we do have some fairly worked out buses that can keep commercial missions done on budget within the fairly well developed parameters of commercial up to GEO. Have, honestly, since the 1980's. Multiple companies from multiple countries have demonstrated this, there is a competitive market for commsats and earth observing satellites (the only two markets where business cases really close). If you are doing science from LEO you can probably re-use a lot of components from those markets.
For exploration missions and anything in deep space (basically, beyond Lunar Orbit) people have kicked around ideas for common buses, there have been plenty of proposals, but no one seems to have enough value in them to be the third or fourth user of one- everyone has found it better to start from scratch than use someone else's bus design. It is possible if there was a sustained, focused effort at one kind of project, say, something where Mars orbiter launches were guaranteed every 26 months for more than a decade, that the investment in a common bus might pay off. But as long as we are bouncing between Mars, Jupiter, Pluto/KBO's, E-S L2, and inside Mercury's orbit, it just isn't actually reusable.
Just as one point, until the past few years everything in the outer planets had to be RTG powered, which requires a totally different design than something solar. It was only with Juno (and now the Europa Clipper) that solar has been demonstrated for outer planets at all, and it is still not exactly a design you'd have off the shelf, nor would the power design you'd want for outer planets solar be at all similar to the design you'd want for inner planets solar. The same is true for comms, for thermal management, for rad-hardening, etc.
I was just thinking about how much pressure there must be on everyone involved in Discovery Class missions. People's entire professional careers, billions of dollars, so much at stake!
Is the pressure something significant, or is it spread across so many people that there is little trouble sleeping at night?
>Is the pressure something significant, or is it spread across so many people that there is little trouble sleeping at night?
When you are on contract for something, you deliver to the contract, and are done when you successfully meet the customer's requirements. So in that sense you don't have the same exposure to the program risks.
However, I've been part of one-off science missions before, and there is a different feeling beyond the contract obligations, though it's certainly abstracted through the many layers of sub-, sub-contracts.
The one that gets to me is the Huygens part of the Cassini-Huygens mission. Cassini was launched October 15th, 1997, Huygens separated from the Cassini carrier on December 25th 2004, and landed on Titan on January 14th, 2005. So it was in space for over 7 years before it got it's 90 minutes of time on the surface. That was actually towards the upper-end of expected lifetime on Titan- somewhere between 30-90 minutes was the expected lifetime of the lander(1). So you build and test and test and test (2) for years before launch, then the probe travels for seven years in outer space, and then it gives you an hour and a half of data and that's it. Your entire life for ... 15 years? Resolved in 90 minutes. On the shorter end of probe lifespan, it would have died before the first signal even reached Earth!
1: Officially I believe the expectation was "3 minutes" but that was a deliberate under-promise so that a success could be declared as long as they got any message at all from the lander on the surface: I have second-hand accounts that 30 minutes was what the scientists considered the minimum.
2: Even with all that testing, disaster almost struck. It wasn't until after the launch that someone realized even all of this testing had missed something important. The radio communications between Cassini and Huygens would be affected by the Doppler shift of Huygens hitting Titan's atmosphere, which would be unpredictable changes to velocity. After launch they had to rejigger when Huygens would be launched to a time when the signals would be perpendicular to the direction of travel so the shift wouldn't affect the radio waves so much that the Cassini receiver firmware (which could not be modified after launch) could still detect the signals.
And also with all of that testing, ESA's instructions to the Cassini probe missed turning on one channel on the receiver and so half of the pictures that Huygens transmitted had nothing listening in and were lost.
> Your entire life for ... 15 years? Resolved in 90 minutes
I ultimately decided against pursuing a career in aerospace engineering after talking to engineers who worked a similar time frame on a project only to watch it get killed in 30 seconds' debate in Congress.
Because it's one shot, must work stuff. They don't build this type of equipment often (really ever) because it's all bespoke to this mission. That means they need to build, verify, test, etc and it all has to work first time because there is only 1 shot (over a 1 month period) for the launch window
I was curious, so I looked up the budget. Development of Europa Clipper cost about $2.5 billion of which $1.1 billion was the spacecraft, $475M was payload, $200M was the launch vehicle (about $230M saved by not using SLS), $160M for ground systems, $60 M for testing. Formulation of Europa Clipper cost $1.2 billion. Operating it will cost about $80M per year.
In the NASA budget, -$230M is the "change from base year estimate" for the launch vehicle. In other words, the launch vehicle ended up being less than half the price of the initial budget estimate. (This is unusual; almost everything goes up from the initial budget.) Originally, congress mandated that Europa Clipper use the SLS to launch. But after vibration problems turned up with SLS, it would take $1 billion to redesign the Clipper. They say the SLS would have cost $1 billion for the launch vehicle. So I think the way the math works out is that SLS rocket cost much more than originally budgeted ($800M more?) and it would have cost another $1 billion to redesign Clipper. So abandoning SLS saved $230 million compared to the original budget but saved $2 billion compared to what SLS would have ended up costing.
Building a ship containing delicate sensors that needs to get into space, arrive at the target, and beam back measurements on the first try with a very low tolerance for error is hard.
On Earth, it's cost-efficient to build things with a reasonable "bathtub curve" failure rate because they can be repaired or (if a consumer product) replaced under warranty. Neither of these are an option in one-off space projects: everything has to be built to ~100% initial reliability, which makes everything much more expensive.
In theory falling launch costs will eventually mean maybe we can make space science missions more disposable so a loss from random failure is no big deal, but we're not quite there yet.
> The etymological origin of the word clipper is uncertain, but is believed to be derived from the English language verb "to clip", which at the time meant "to run or fly swiftly".[2]
> Because Europa Clipper needs a lot of energy to start it on its interplanetary trajectory to Jupiter, the rocket for this launch will be fully expendable, with the exception of a recoverable fairing. This means that there will be no return of first-stage boosters for this launch. Although SpaceX has flown a fully expendable Falcon Heavy before, this is the first time that NASA’s Launch Services Program is launching a mission for the agency with this Falcon Heavy configuration, though the program has extensive experience now with both expendable as well as reusable rockets. In addition to not recovering any boosters, technicians removed components only needed for reuse to increase the performance of the rocket, to launch the largest planetary spacecraft NASA has ever developed and give it the power it needs to travel to Jupiter.
That's awesome flexibility. I'm guessing that meant they could omit landing legs, whatever powers them, and anything to do with engine re-pressurization and restart. Any extra fuel for boostback and landing can now go into S2 delta v.
Nope. They needed the maximum amount of thrust from those boosters in order to propel the spacecraft toward Jupiter, so they couldn't save enough fuel for the boosters to land themselves. This was the 6th flight of these boosters, so we thank them for their service!
It's an engineering tradeoff of payload vs. booster cost. It's heavily one-sided for this launch—you get 4x more payload to this interplanetary orbit with the expendable Heavy vs. the reusable one [a].
Future launches with Starship, analogous to this one, would refuel their upper stage in orbit to their full capacity, so there would be no performance downside to recovering boosters; you would need more launches, but they would all be reusable.
Also with starship launches only needing about a million dollars in fuel, it makes a ton of sense to just launch fuel to orbit versus sacrificing an entire ship
It's limited by physics: if a reusable rocket can carry a maximum payload of X tons, it can only be reused when it carries a payload of X/N tons, and (1-X)/N as extra fuel. How large X and N are of course depends on the rocket design, but N is always going to be greater than 1.
So, for any rocket, flying it reusably is going to mean not using the full capacity.
You could build a larger re-usable rocket that could launch this payload and still have margin for recovery, such as the in-development SpaceX Starship.
However for this type of mission that would still leave the question of "What if we skipped re-usability and paid more to expend the launcher? Could we launch a larger payload and/or get there faster?"
The trajectory for this mission was already a slower transit time than the alternate plan of launching it on the SLS rocket. I think for some missions that are infrequent and targeting far-away destinations there will always be a desire to maximize performance at the cost of reusability on that singular launch.
It's limited by physics: Recovering the rockets requires counteracting gravity, which requires energy. If the energy is needed for something else - in this case for additional propulsion - then it's not available for recovery.
It's the tyranny of the rocket equation. The more you send up, the more fuel you need to send up and then you need to send fuel to lift that fuel and then fuel to lift that fuel and so on.
Since you have to have a burn to slow down and land you have to carry extra fuel to recover. That's always going to be the case, but starship is making strides towards minimizing that as much as possible with belly flops and chopsticks
Sure, a bigger rocket could carry this particular payload while being reusable. But for any rocket there will always be payloads it can't carry while also having enough fuel to land.
ETA is 2030. Originally planned for a rocket (SLS) which would have delivered the Clipper in ~3 yrs, but which was decided to be not viable for the Clipper (with some lobbying suspected).
How much science is delayed by the extra 2+ years? Looking at the 'project plan', is the Clipper's arrival (and delivery of data) on the critical path for research? And how much research?
I'm picturing a lot of scientists and research projects waiting an extra 2-3 years, and then all the research, follow-on missions, etc. also delayed. Essentially, the decision might shift everything in this field 2-3 years further away, and then centuries from now human habitation of other planets is 2-3 years later (ok, a bit exaggerated).
But seriously, maybe it's not on the critical path or doesn't impact that much. Is anyone here familiar with the research?
The lobbying was from the SLS side. Congress was set on forcing Europa Clipper to fly on SLS regardless of technicalities and only backed off because the Europa Clipper team made it clear they'd want an additional $1B to make the spacecraft able to handle the exceedingly rough ride SLS provides. They were perfectly happy handing $2B of taxpayer money to Boeing, but were unwilling to spend another $1B on science.
On top of that, it's worth considering that SLS wouldn't be ready to fly right now anyway. As it stands, they can't even manage to build one rocket per year, the Artemis-2 rocket has already been delayed to next year, so, Clipper would've launched 2-3 years later anyway.
You don't think SpaceX did any lobbying? They just passively stood aside? Look at this story, about SpaceX, via the Project 2025 think tank's FOIA requests, searching for NASA employees who has written things critical of SpaceX:
It's really hard to discuss any topic that brushes SpaceX tangentially on HN. I asked about the research, not about the rockets, but if one even mentions SpaceX in anything less than glowing terms they get six (so far) responses re rockets, all defending SpaceX, and not a mention of the research.
NASA and SLS are actually the property of the people posting; their mission is to serve all Americans. SpaceX is a private business, whose mission is to serve only itself and, in the practice of its owner's businesses, has zero regard for everyone else.
In that context it's bizarre that people are fans of the latter. In context of social media, where mass influence is bought, it's perhaps what we'd expect - that's not NASA's business.
>It's really hard to discuss any topic that brushes SpaceX tangentially on HN. I asked about the research, not about the rockets, but if one even mentions SpaceX in anything less than glowing terms they get six (so far) responses re rockets, all defending SpaceX, and not a mention of the research.
Everyone's just pointing out the obvious fact that SLS wasn't going to be able to do the mission on time or at cost anyway, so the delays were happening regardless, and Falcon Heavy was the only other option. You phrased your question with the assumption that SLS was going to launch on-time, added in the implication that SpaceX lobbied for the launch and caused research to be delayed by a few years, then decided to complain that everyone else was being biased.
>NASA and SLS are actually the property of the people posting; their mission is to serve all Americans. SpaceX is a private business, whose mission is to serve only itself and, in the practice of its owner's businesses, has zero regard for everyone else.
SLS is the property of Boeing, another private business. Its mission is to transfer vast sums of taxpayer money to Boeing under a contract whose terms remove any expectations of good performance and whose use in Artemis is legally mandated by Congress for no technical reason. The NASA Office of Inspector General has constantly been expressing serious concerns over how bad of a deal SLS is for the American people. We've also had genuine technological progress held back because Congressmen wanted to transfer money to SLS. Its ever inflating costs threaten actually useful science programs every year. I don't see how anyone who actually wants American leadership in space can support it.
SpaceX, as you have noted, is also a private business. With NASA being one of its biggest customers, they are obviously beholden to NASA's desires. Unlike Boeing, who has explicitly expressed their intent to refuse contracts which properly hold the company responsible for under-performing, SpaceX consistently insists on such contracts. Currently, they provide most launch services to NASA and have saved NASA billions over the years. They maintain a mutually beneficial relationship, where NASA gains all sorts of valuable data and capabilities from SpaceX's private development efforts, and SpaceX gains business from NASA.
If you're dismissing this as a social media influence thing, despite all the technical points presented to you, then all that shows is that you were just concern trolling in your original post and have no interest in actually having your question answered.
By theory and - especially these days - by practice, private business is there to enrich its owners.
One way it does that is to serve customers, another is to manipulate, cheat, and squeeze them of every dime the business can get, and then drop them for higher-margin customers. Just look at modern business.
Using a commercial launch vehicle reduced the cost quite a bit (saved a billion on the vehicle itself and another billion by not having to design the payload to pass SLS's much more rigorous vibe checks). The $2b saved is about 10% of NASA's annual budget. The next mission to Titan has a budget of around $3b, for reference.
On top of that, there's no guarantee SLS would've actually been able to launch on schedule. The program has had a lot of setbacks, to put it lightly, and has only launched once so far (6 years later than it's original ETA). There's additional rockets in production but if it came down to it the manned SLS missions would probably get priority for political reasons.
> In late 2015, Congress directed NASA to launch Europa Clipper using the Space Launch System (SLS), NASA’s massive moon rocket.
> The SLS was still in development at the time, and would be for a number of years to come. Delays with the powerful rocket, and the need to dedicate at least the first three SLS vehicles to launches for NASA's Artemis moon program, pushed Europa Clipper’s liftoff date into limbo. (SLS debuted in late 2022, successfully sending the uncrewed Artemis 1 mission to the moon.)
> The 2021 U.S. House of Representatives budget proposal instructed NASA to launch Europa Clipper by 2025, and to do so on an SLS "if available." Those two crucial words put the probe on a path toward a commercial launch vehicle, which turned out to be a Falcon Heavy.
So while the flight time may be longer, at least the entire mission is derisked in that it was forced to get off the ground instead of wait for an appropriate gap within the SLS's launch capacity.
I don't have any special insider information, but from what I know about spaceflight I think we should be glad they used the Falcon Heavy instead of SLS.
SLS has been consistently delayed pretty much every year since its conception, most recently the Artemis 2 mission which was supposed to fly this year is now delayed to next. It has only flown one time, now two years ago. It's also an order of magnitude more expensive than the Falcon Heavy with each flight costing upwards of $2 billion.
My guess is if they had been stuck with SLS this mission would not get to Europa until significantly later, if at all.
Well, Congress specified it to use SLS, since they were looking for extra payloads. And then uncoupled it from SLS when it became clear it couldn't even handle one extra payload.
NASA, wisely, always benchmarked the mission on Falcon Heavy, and bailed from SLS as soon as they were allowed to.
Clipper on SLS was more of a "wouldn't it be neat" scenario than the intended mission design.
This presumes that an additional SLS rocket would have been completed and ready to launch in the same timeframe as this launch on Falcon Heavy. From what I have seen of the SLS program I think that is an unlikely scenario.
I love JPL's straightforward bio:
https://www.nasa.gov/jpl/jet-propulsion-laboratory-history/
"JPL led the U.S. into space with Explorer 1, the first U.S. satellite, and joined NASA shortly after the agency formed in 1958. JPL spacecraft have flown to every planet in the solar system, the Sun, and into interstellar space in a quest to better understand the origins of the universe, and of life."
Not many organizations can say that: We've flown to every planet in the solar system. Wow. (And of course, they've done more than that.)
Alternate streams with commentary...
Everyday Astronaut: https://www.youtube.com/watch?v=IAixoyE78rE
NASA Spaceflight: https://www.youtube.com/watch?v=9JUn8LmGYEA (This is not an official NASA stream)
And for people who prefer text: https://www.washingtonpost.com/science/2024/10/14/europa-cli...
> The journey to the Jupiter system is expected to take five and a half years, arriving April 11, 2030, for four years of observations.
See you in five years!
Cool, I finally have something to live for
Hopefully we'll see humans back on the Moon, and cheap reusable human-rated spacecraft on Mars, before then.
The NASA+ stream died for me "404 The cosmic object you were looking for has disappeared beyond the event horizon." I much preferred the old IBM stream they used to use. Shame, but at least it sounds like the launch was a success.
Spaceflight Now: https://www.youtube.com/watch?v=tZjszhRVo9s
https://en.wikipedia.org/wiki/Europa_Clipper#Launch_and_traj...
really cool to see the trajectory:
- earth mars gravity assists
- complex trajectory around jupiter and its moons
Damn, I am impressed how nonchalantly the flagship NASA mission was using the reused boosters, dirty from soot.
NASA prefer them now, as they're "flight proven".
They're using them to launch astronauts now too.
Nothing nonchalant about it. There was a stringent qualification process.
The time between boosters first being reused in Falcons and this mission is the same as the time between JFK's 'we choose to go to the moon' speech and the actual moon landings.
Cost of the Europa Clipper program is around $4-5 billion. Can anyone in the industry shed some light on why these programs are so expensive?
I worked on one component of the spacecraft which was a derivative of something we've built may times before. However, the test program was entirely unique to Europa Clipper, and most of the cost was in this bespoke testing. The use of a "heritage" component served mostly to lower risk; it did not save much cost overall.
There’s also politics at play. Public space agencies need to keep the absolute number of failures down to keep funding flowing, even if it costs absurd amounts to do it due to rapidly diminishing returns. This is especially important to flagship missions.
When I took Ae105 at Caltech, the NASA MSL project manager explained it like this (I remember the numbers he used clearly): a mission might cost $500 million with an 80% chance of success, or they can spend twice as much to increase the chance of success to 95% by investing a lot more in upfront testing and R&D. Now, the smart thing to do - given a billion dollar budget - is to take that first option because if it fails you can try again and the probability of both attempts failing is only 4%, compared to 5% for the expensive single mission. Then you’ve got an 80% chance of having $500 million left over for a different mission.
The public and decision makers react irrationally to any failure, putting funding for other missions and the entire program in jeopardy. NASA and ESA have to make some extremely suboptimal decisions to make sure that funding doesn’t get catastrophically cut.
The above is the example the instructor used to easily illustrate his point but he said the real numbers are even more stark. Often times the cost savings of just building a second copy of the payload along with the first means it costs $600 million for the first attempt, and only $200 million for the second (the cost of the launch vehicle and keeping people on staff), saving hundreds of millions overall.
> The public and decision makers react irrationally to any failure, putting funding for other missions and the entire program in jeopardy. NASA and ESA have to make some extremely suboptimal decisions to make sure that funding doesn’t get catastrophically cut.
Which, incidentally, is one of the key reasons SpaceX has had the success they have: they're set up to handle failure and avoid this politics. How many Starships have blown up? If Starship were a NASA program, how many explosions ago would it have been cancelled? And yet this approach to risk is pretty effective!
Isn't that partly or largely due to Musk's influence? Like many powerful influencers, Musk can reliably rally supporters to even an unreality.
Compare the responses to a failure by Boeing or SLS and to a failure by SpaceX.
Also, SpaceX hasn't had a serious non-experimental failure yet (?). I'm sure their PR is preparing for that eventuality, but when non-fans are upset over a bad outcome and then learn about the risk tolerated, they will swing from admiring risk to condemning it. Imagine the Congressional committees.
Even if SpaceX is super-conservative when flying humans (which we shouldn't assume - cultures tend to be consistent), if someone dies then all that risk-seeking behavior will be attacked.
(To be clear, as long as SpaceX can manage risk in production - i.e., with high-value payloads such as people and NASA flagships - I think they and everyone else should use risk efficiently.)
> Also, SpaceX hasn't had a serious non-experimental failure yet
SpaceX had an explosive failure in 2016 with a commercial payload onboard.
Thanks. How valuable was the payload?
It's really frustrating that there's not a way to educate the public on simple concepts like this. You'd think the out-in-the-open development approach of SpaceX, for instance, would make it blatantly obvious how much money they're saving by permitting failure...yet the news continually spins their less-than-perfectly successful test launches as undesirable. And space spending is perhaps one of the least consequential areas of government where this failure of the herd to comprehend reality applies.
The public are smarter than you give them credit for. For the most part space missions are contests between governments and those governed with science as a consolation price. If you are part of team A do you want to have to come up with reasoning on why you lost? No. Does anyone care if a billionaire's toy gets blown up? No. The obvious choice to eliminate all risk would be not to play, but that is not an option; the other is to delay and delay some more. Thus, SLS.
It's easy to imagine 3-4 years of projects failing and someone grandstanding about it, space exploration is a pointless endeavor to a lot of people
And can introduce unusual failure cases for these bespoke missions. Mars Observer was lost in flight to Mars three decades ago, probably because of the inappropriate reuse of a satellite rocket engine. (1) The space environment out around Jupiter is really quite different from the environment that the JWST is facing around E-S L2 or what the Parker Solar Probe is facing right near the Sun. Even if the component is spec'd to handle the environment, you need to have actual educated humans (read: expensive labor) determine what those conditions will be, and then verify that the part will meet it, and that's where the money goes- to pay all of those humans.
If you built even 15 Europa Clippers the cost per-item would come down enormously (because all of those people's work could be re-used), but since the 1970's NASA has not had the budget for multiple probes per missions. So every mission is bespoke, and has to be done again completely from scratch.
1: The engine was normally used for circularizing the orbit of a geosynch comm satellite, so within a few hours of flight. For doing a Mars Insertion burn it needed to sit fueled for months in outer space, which was not appropriately tested, and probably the fuel tank exploded in flight because of that.
> So every mission is bespoke, and has to be done again completely from scratch.
Is there room here for making things more reusable? For example, instead of creating one big satellite with tens of instruments, how about they create 10 satellites with one instrument each? or would that still be too bespoke to lower the cost per item?
While we now live in an era of abundant rocket launches, it used to cost far more to launch with very few launches per year.
The whole strategies of exploration haven’t shifted yet to this new paradigm. Hopefully NASA starts making smaller probes and launching them far more often.
Europa Clipper is literally the largest thing ever launched to the outer planets (so big that Falcon Heavy can't be reused for this mission, they have to throw it all away in order to get every last jot of performance out of the rocket- so this is not an "abundant rocket launches" situation- this is a fully expendable rocket just like an Atlas V). And the size is not for fun, but because going close to Europa (the entire point of the mission) means going through the second strongest set of EM and radiation belts in our solar system. Even with this size- meaning it can have a lot more shielding than normal- the probe can only survive a few months of the radiation from Jupiter's van Allen belts. The plan is to break that few months of exposure up over about four years of calendar time, by having it do highly elliptical orbits so it stores a lot of data during a close flyby of Europa and then transmits that all back to Earth while it is far outside of Jupiter's radiation storm, then it can head back down and collect more data. And that lengthy transmission time is because it is sending information from so far away- and has so little juice that the effective bandwidth is tiny.
It is possible for a swarm of small satellites to fill niches in space exploration. Closely studying Europa isn't really one of them with today's technology.
Yeah. I'm surprised that we don't have a standard deep space probe bus by now in at least serial production, at least for orbiters if not landers, rovers, and such.
Each mission has unique requirements, but since payload mass costs are coming down, ISTM it should be possible to create a standard buss that meets most requirements most of the rime, even if it's heavier than a bespoke effort for any one mission.
For things in Earth orbit (LEO all the way up to GEO) we do have some fairly worked out buses that can keep commercial missions done on budget within the fairly well developed parameters of commercial up to GEO. Have, honestly, since the 1980's. Multiple companies from multiple countries have demonstrated this, there is a competitive market for commsats and earth observing satellites (the only two markets where business cases really close). If you are doing science from LEO you can probably re-use a lot of components from those markets.
For exploration missions and anything in deep space (basically, beyond Lunar Orbit) people have kicked around ideas for common buses, there have been plenty of proposals, but no one seems to have enough value in them to be the third or fourth user of one- everyone has found it better to start from scratch than use someone else's bus design. It is possible if there was a sustained, focused effort at one kind of project, say, something where Mars orbiter launches were guaranteed every 26 months for more than a decade, that the investment in a common bus might pay off. But as long as we are bouncing between Mars, Jupiter, Pluto/KBO's, E-S L2, and inside Mercury's orbit, it just isn't actually reusable.
Just as one point, until the past few years everything in the outer planets had to be RTG powered, which requires a totally different design than something solar. It was only with Juno (and now the Europa Clipper) that solar has been demonstrated for outer planets at all, and it is still not exactly a design you'd have off the shelf, nor would the power design you'd want for outer planets solar be at all similar to the design you'd want for inner planets solar. The same is true for comms, for thermal management, for rad-hardening, etc.
There are somewhat standard busses. Though you're correct, many use custom busses for their specific missions.
https://en.wikipedia.org/wiki/Comparison_of_satellite_buses
For example, the SSL 1300 apparently has hosted 118 satellites so far:
https://en.wikipedia.org/wiki/SSL_1300
Though maybe the distinction between "satellite" and "spacecraft" bears importance here.
Oh cool, someone that actually worked on it!
I was just thinking about how much pressure there must be on everyone involved in Discovery Class missions. People's entire professional careers, billions of dollars, so much at stake!
Is the pressure something significant, or is it spread across so many people that there is little trouble sleeping at night?
>Is the pressure something significant, or is it spread across so many people that there is little trouble sleeping at night?
When you are on contract for something, you deliver to the contract, and are done when you successfully meet the customer's requirements. So in that sense you don't have the same exposure to the program risks.
However, I've been part of one-off science missions before, and there is a different feeling beyond the contract obligations, though it's certainly abstracted through the many layers of sub-, sub-contracts.
The one that gets to me is the Huygens part of the Cassini-Huygens mission. Cassini was launched October 15th, 1997, Huygens separated from the Cassini carrier on December 25th 2004, and landed on Titan on January 14th, 2005. So it was in space for over 7 years before it got it's 90 minutes of time on the surface. That was actually towards the upper-end of expected lifetime on Titan- somewhere between 30-90 minutes was the expected lifetime of the lander(1). So you build and test and test and test (2) for years before launch, then the probe travels for seven years in outer space, and then it gives you an hour and a half of data and that's it. Your entire life for ... 15 years? Resolved in 90 minutes. On the shorter end of probe lifespan, it would have died before the first signal even reached Earth!
1: Officially I believe the expectation was "3 minutes" but that was a deliberate under-promise so that a success could be declared as long as they got any message at all from the lander on the surface: I have second-hand accounts that 30 minutes was what the scientists considered the minimum.
2: Even with all that testing, disaster almost struck. It wasn't until after the launch that someone realized even all of this testing had missed something important. The radio communications between Cassini and Huygens would be affected by the Doppler shift of Huygens hitting Titan's atmosphere, which would be unpredictable changes to velocity. After launch they had to rejigger when Huygens would be launched to a time when the signals would be perpendicular to the direction of travel so the shift wouldn't affect the radio waves so much that the Cassini receiver firmware (which could not be modified after launch) could still detect the signals. And also with all of that testing, ESA's instructions to the Cassini probe missed turning on one channel on the receiver and so half of the pictures that Huygens transmitted had nothing listening in and were lost.
> Your entire life for ... 15 years? Resolved in 90 minutes
I ultimately decided against pursuing a career in aerospace engineering after talking to engineers who worked a similar time frame on a project only to watch it get killed in 30 seconds' debate in Congress.
Thanks for that. It made me wonder: who was it? Were they in the shower, did they awake from a nightmare?
Here is an HN post from 2014, "How a Swedish engineer saved a once-in-a-lifetime mission to Titan (2004)" [0]
Since the link has rotted away, here is the archive link to the IEEE story. [1]
[0] https://news.ycombinator.com/item?id=7472495
[1] https://archive.is/3oj6P (archive.org is still not working reliably)
Because it's one shot, must work stuff. They don't build this type of equipment often (really ever) because it's all bespoke to this mission. That means they need to build, verify, test, etc and it all has to work first time because there is only 1 shot (over a 1 month period) for the launch window
I was curious, so I looked up the budget. Development of Europa Clipper cost about $2.5 billion of which $1.1 billion was the spacecraft, $475M was payload, $200M was the launch vehicle (about $230M saved by not using SLS), $160M for ground systems, $60 M for testing. Formulation of Europa Clipper cost $1.2 billion. Operating it will cost about $80M per year.
Details on the Europa Clipper budget are at https://www.nasa.gov/wp-content/uploads/2023/03/nasa-fy-2024...
(Edit: fixed billion/million typo)
> (about $230M saved by not using SLS)
Since SLS launches are now upwards of $2B per launch by some estimates, how does this math work? Wikipedia also suggests $2 billion saved.
https://en.wikipedia.org/wiki/Space_Launch_System#Europa_Cli...
In the NASA budget, -$230M is the "change from base year estimate" for the launch vehicle. In other words, the launch vehicle ended up being less than half the price of the initial budget estimate. (This is unusual; almost everything goes up from the initial budget.) Originally, congress mandated that Europa Clipper use the SLS to launch. But after vibration problems turned up with SLS, it would take $1 billion to redesign the Clipper. They say the SLS would have cost $1 billion for the launch vehicle. So I think the way the math works out is that SLS rocket cost much more than originally budgeted ($800M more?) and it would have cost another $1 billion to redesign Clipper. So abandoning SLS saved $230 million compared to the original budget but saved $2 billion compared to what SLS would have ended up costing.
I bet you it’s what the project would have been charged by the SLS program, but SLS would have lost a billion by providing a launch.
> $200 billion was the launch vehicle
Million I'd assume?
Building a ship containing delicate sensors that needs to get into space, arrive at the target, and beam back measurements on the first try with a very low tolerance for error is hard.
On Earth, it's cost-efficient to build things with a reasonable "bathtub curve" failure rate because they can be repaired or (if a consumer product) replaced under warranty. Neither of these are an option in one-off space projects: everything has to be built to ~100% initial reliability, which makes everything much more expensive.
In theory falling launch costs will eventually mean maybe we can make space science missions more disposable so a loss from random failure is no big deal, but we're not quite there yet.
ATTEMPT NO LANDING THERE.
They haven't given me my monolith, so no contract established
Veritasium video on the Clipper probe/mission:
* https://www.youtube.com/watch?v=DJO_9auJhJQ
Real Engineering:
* https://www.youtube.com/watch?v=SzKkBOUvsAY
Probe named after the sailing ship design:
> The etymological origin of the word clipper is uncertain, but is believed to be derived from the English language verb "to clip", which at the time meant "to run or fly swiftly".[2]
* https://en.wikipedia.org/wiki/Clipper
Not common but I have heard “moving at a fair clip” to describe speed in commentary and conversation.
Perhaps the term hasn’t quite died out.
Are the side boosters going to be recovered?
Per NASA, no
> Because Europa Clipper needs a lot of energy to start it on its interplanetary trajectory to Jupiter, the rocket for this launch will be fully expendable, with the exception of a recoverable fairing. This means that there will be no return of first-stage boosters for this launch. Although SpaceX has flown a fully expendable Falcon Heavy before, this is the first time that NASA’s Launch Services Program is launching a mission for the agency with this Falcon Heavy configuration, though the program has extensive experience now with both expendable as well as reusable rockets. In addition to not recovering any boosters, technicians removed components only needed for reuse to increase the performance of the rocket, to launch the largest planetary spacecraft NASA has ever developed and give it the power it needs to travel to Jupiter.
https://blogs.nasa.gov/europaclipper/2024/10/14/nasa-launch-...
That's awesome flexibility. I'm guessing that meant they could omit landing legs, whatever powers them, and anything to do with engine re-pressurization and restart. Any extra fuel for boostback and landing can now go into S2 delta v.
They also removed the gridfins and their engines.
https://blogs.nasa.gov/europaclipper/wp-content/uploads/site...
Nope. They needed the maximum amount of thrust from those boosters in order to propel the spacecraft toward Jupiter, so they couldn't save enough fuel for the boosters to land themselves. This was the 6th flight of these boosters, so we thank them for their service!
Is this one of those things that’s limited by physics or at some point will these kinds of missions be doable with a mostly reusable setup?
It's an engineering tradeoff of payload vs. booster cost. It's heavily one-sided for this launch—you get 4x more payload to this interplanetary orbit with the expendable Heavy vs. the reusable one [a].
Future launches with Starship, analogous to this one, would refuel their upper stage in orbit to their full capacity, so there would be no performance downside to recovering boosters; you would need more launches, but they would all be reusable.
[a] https://elvperf.ksc.nasa.gov/Pages/Query.aspx (I queried for a high-energy orbit with a C3 of 42 km^2/s^2, which I think is correct, or at least very close)
Also with starship launches only needing about a million dollars in fuel, it makes a ton of sense to just launch fuel to orbit versus sacrificing an entire ship
It's limited by physics: if a reusable rocket can carry a maximum payload of X tons, it can only be reused when it carries a payload of X/N tons, and (1-X)/N as extra fuel. How large X and N are of course depends on the rocket design, but N is always going to be greater than 1.
So, for any rocket, flying it reusably is going to mean not using the full capacity.
You could build a larger re-usable rocket that could launch this payload and still have margin for recovery, such as the in-development SpaceX Starship.
However for this type of mission that would still leave the question of "What if we skipped re-usability and paid more to expend the launcher? Could we launch a larger payload and/or get there faster?"
The trajectory for this mission was already a slower transit time than the alternate plan of launching it on the SLS rocket. I think for some missions that are infrequent and targeting far-away destinations there will always be a desire to maximize performance at the cost of reusability on that singular launch.
It's limited by physics: Recovering the rockets requires counteracting gravity, which requires energy. If the energy is needed for something else - in this case for additional propulsion - then it's not available for recovery.
It's the tyranny of the rocket equation. The more you send up, the more fuel you need to send up and then you need to send fuel to lift that fuel and then fuel to lift that fuel and so on.
Since you have to have a burn to slow down and land you have to carry extra fuel to recover. That's always going to be the case, but starship is making strides towards minimizing that as much as possible with belly flops and chopsticks
It's a limitation of the Falcon Heavy, the launcher used this time. A future, more powerful one could do it while being reusable.
Sure, a bigger rocket could carry this particular payload while being reusable. But for any rocket there will always be payloads it can't carry while also having enough fuel to land.
That constraint can be significantly mitigated by in-space refueling. Then it just becomes a matter of what the rocket can lift into a stable orbit.
Edit: Not that this applies to any currently operational rockets.
They traded off the expense of expending a whole Falcon Heavy against the benefit of having additional delta-V to get to Jupiter faster.
The suspiciously clean white areas on all three boosters where the landing legs have been removed are good indicators of what's planned.
Not this time, only the payload fairing.
It's wild that the only thing they recover is the last thing they jettison!
Lightweight enough to be recovered via parachute system, unlike the big heavy boosters which need thrust!
No. All cores expended in this launch.
can't wait to try some tasty Europafish
For a moment I though this is European space agency sending a rocket :'(
ETA is 2030. Originally planned for a rocket (SLS) which would have delivered the Clipper in ~3 yrs, but which was decided to be not viable for the Clipper (with some lobbying suspected).
How much science is delayed by the extra 2+ years? Looking at the 'project plan', is the Clipper's arrival (and delivery of data) on the critical path for research? And how much research?
I'm picturing a lot of scientists and research projects waiting an extra 2-3 years, and then all the research, follow-on missions, etc. also delayed. Essentially, the decision might shift everything in this field 2-3 years further away, and then centuries from now human habitation of other planets is 2-3 years later (ok, a bit exaggerated).
But seriously, maybe it's not on the critical path or doesn't impact that much. Is anyone here familiar with the research?
> (with some lobbying suspected)
The lobbying was from the SLS side. Congress was set on forcing Europa Clipper to fly on SLS regardless of technicalities and only backed off because the Europa Clipper team made it clear they'd want an additional $1B to make the spacecraft able to handle the exceedingly rough ride SLS provides. They were perfectly happy handing $2B of taxpayer money to Boeing, but were unwilling to spend another $1B on science.
On top of that, it's worth considering that SLS wouldn't be ready to fly right now anyway. As it stands, they can't even manage to build one rocket per year, the Artemis-2 rocket has already been delayed to next year, so, Clipper would've launched 2-3 years later anyway.
You don't think SpaceX did any lobbying? They just passively stood aside? Look at this story, about SpaceX, via the Project 2025 think tank's FOIA requests, searching for NASA employees who has written things critical of SpaceX:
https://news.ycombinator.com/item?id=41757578
It's really hard to discuss any topic that brushes SpaceX tangentially on HN. I asked about the research, not about the rockets, but if one even mentions SpaceX in anything less than glowing terms they get six (so far) responses re rockets, all defending SpaceX, and not a mention of the research.
NASA and SLS are actually the property of the people posting; their mission is to serve all Americans. SpaceX is a private business, whose mission is to serve only itself and, in the practice of its owner's businesses, has zero regard for everyone else.
In that context it's bizarre that people are fans of the latter. In context of social media, where mass influence is bought, it's perhaps what we'd expect - that's not NASA's business.
>It's really hard to discuss any topic that brushes SpaceX tangentially on HN. I asked about the research, not about the rockets, but if one even mentions SpaceX in anything less than glowing terms they get six (so far) responses re rockets, all defending SpaceX, and not a mention of the research.
Everyone's just pointing out the obvious fact that SLS wasn't going to be able to do the mission on time or at cost anyway, so the delays were happening regardless, and Falcon Heavy was the only other option. You phrased your question with the assumption that SLS was going to launch on-time, added in the implication that SpaceX lobbied for the launch and caused research to be delayed by a few years, then decided to complain that everyone else was being biased.
>NASA and SLS are actually the property of the people posting; their mission is to serve all Americans. SpaceX is a private business, whose mission is to serve only itself and, in the practice of its owner's businesses, has zero regard for everyone else.
SLS is the property of Boeing, another private business. Its mission is to transfer vast sums of taxpayer money to Boeing under a contract whose terms remove any expectations of good performance and whose use in Artemis is legally mandated by Congress for no technical reason. The NASA Office of Inspector General has constantly been expressing serious concerns over how bad of a deal SLS is for the American people. We've also had genuine technological progress held back because Congressmen wanted to transfer money to SLS. Its ever inflating costs threaten actually useful science programs every year. I don't see how anyone who actually wants American leadership in space can support it.
SpaceX, as you have noted, is also a private business. With NASA being one of its biggest customers, they are obviously beholden to NASA's desires. Unlike Boeing, who has explicitly expressed their intent to refuse contracts which properly hold the company responsible for under-performing, SpaceX consistently insists on such contracts. Currently, they provide most launch services to NASA and have saved NASA billions over the years. They maintain a mutually beneficial relationship, where NASA gains all sorts of valuable data and capabilities from SpaceX's private development efforts, and SpaceX gains business from NASA.
If you're dismissing this as a social media influence thing, despite all the technical points presented to you, then all that shows is that you were just concern trolling in your original post and have no interest in actually having your question answered.
> private business, whose mission is to serve only itself
Any private business's primary mission is to serve its customers - in order to even exist.
By theory and - especially these days - by practice, private business is there to enrich its owners.
One way it does that is to serve customers, another is to manipulate, cheat, and squeeze them of every dime the business can get, and then drop them for higher-margin customers. Just look at modern business.
Using a commercial launch vehicle reduced the cost quite a bit (saved a billion on the vehicle itself and another billion by not having to design the payload to pass SLS's much more rigorous vibe checks). The $2b saved is about 10% of NASA's annual budget. The next mission to Titan has a budget of around $3b, for reference.
On top of that, there's no guarantee SLS would've actually been able to launch on schedule. The program has had a lot of setbacks, to put it lightly, and has only launched once so far (6 years later than it's original ETA). There's additional rockets in production but if it came down to it the manned SLS missions would probably get priority for political reasons.
> In late 2015, Congress directed NASA to launch Europa Clipper using the Space Launch System (SLS), NASA’s massive moon rocket.
> The SLS was still in development at the time, and would be for a number of years to come. Delays with the powerful rocket, and the need to dedicate at least the first three SLS vehicles to launches for NASA's Artemis moon program, pushed Europa Clipper’s liftoff date into limbo. (SLS debuted in late 2022, successfully sending the uncrewed Artemis 1 mission to the moon.)
> The 2021 U.S. House of Representatives budget proposal instructed NASA to launch Europa Clipper by 2025, and to do so on an SLS "if available." Those two crucial words put the probe on a path toward a commercial launch vehicle, which turned out to be a Falcon Heavy.
So while the flight time may be longer, at least the entire mission is derisked in that it was forced to get off the ground instead of wait for an appropriate gap within the SLS's launch capacity.
[1] https://www.space.com/spacex-falcon-heavy-europa-clipper-lau...
I don't have any special insider information, but from what I know about spaceflight I think we should be glad they used the Falcon Heavy instead of SLS.
SLS has been consistently delayed pretty much every year since its conception, most recently the Artemis 2 mission which was supposed to fly this year is now delayed to next. It has only flown one time, now two years ago. It's also an order of magnitude more expensive than the Falcon Heavy with each flight costing upwards of $2 billion.
My guess is if they had been stuck with SLS this mission would not get to Europa until significantly later, if at all.
Well, Congress specified it to use SLS, since they were looking for extra payloads. And then uncoupled it from SLS when it became clear it couldn't even handle one extra payload.
NASA, wisely, always benchmarked the mission on Falcon Heavy, and bailed from SLS as soon as they were allowed to.
Clipper on SLS was more of a "wouldn't it be neat" scenario than the intended mission design.
This presumes that an additional SLS rocket would have been completed and ready to launch in the same timeframe as this launch on Falcon Heavy. From what I have seen of the SLS program I think that is an unlikely scenario.