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NASA's Europa Clipper Launch

218 points by belter 2y ago

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sidcool 2y ago
Are the side boosters going to be recovered?
- ceejayoz 2y ago
  No. All cores expended in this launch.
- benjismith 2y ago
  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!
  - linotype 2y ago
    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?
    - malfist 2y ago
      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
    - alfiopuglisi 2y ago
      It's a limitation of the Falcon Heavy, the launcher used this time. A future, more powerful one could do it while being reusable.
      - tsimionescu 2y ago
        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.
        dotnet00 2y ago
        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.
    - tsimionescu 2y ago
      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.
    - perihelions 2y ago
      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 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)
      - whamlastxmas 2y ago
        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
    - mmooss 2y ago
      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.
    - ls612 2y ago
      They traded off the expense of expending a whole Falcon Heavy against the benefit of having additional delta-V to get to Jupiter faster.
    - stetrain 2y ago
      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.
    - panick21_ 2y ago
      You just go to distributed launch. You launch a rocket multiple times, fuel up and use that to escape. If you use your upper stage as the primary, its unlikely to ever come back. But in future you would potentially have special boost stage for that. See something like Impulse Space is building. But for these really powerful throws, its probably just cheaper to just drop an upper stage. Upper stages are a drop in the bucket compared to the cost of a flagship mission. A Falcon 9 upper stage is only a couple million $.
- pedrosbmartins 2y ago
  Not this time, only the payload fairing.
  - bryanlarsen 2y ago
    It's wild that the only thing they recover is the last thing they jettison!
    - SonicScrub 2y ago
      Lightweight enough to be recovered via parachute system, unlike the big heavy boosters which need thrust!
- wlesieutre 2y ago
  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-manager-gives-go-for-launch/ https://blogs.nasa.gov/europaclipper/2024/10/14/nasa-launch-...
  - imglorp 2y ago
    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.
    - wolf550e 2y ago
      They also removed the gridfins and their engines. https://blogs.nasa.gov/europaclipper/wp-content/uploads/sites/378/2024/10/Europa_vertical_sunrise_101324_DSC_7128.jpg https://blogs.nasa.gov/europaclipper/wp-content/uploads/site...
- moffkalast 2y ago
  The suspiciously clean white areas on all three boosters where the landing legs have been removed are good indicators of what's planned.
throw0101c 2y ago
Veritasium video on the Clipper probe/mission: * https://www.youtube.com/watch?v=DJO_9auJhJQ https://www.youtube.com/watch?v=DJO_9auJhJQ Real Engineering: * https://www.youtube.com/watch?v=SzKkBOUvsAY 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 https://en.wikipedia.org/wiki/Clipper
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- stoneman24 2y ago
  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.
payamb 2y ago
ATTEMPT NO LANDING THERE.
- imzadi 2y ago
  They haven't given me my monolith, so no contract established
DiscourseFan 2y ago
can't wait to try some tasty Europafish
mmooss 2y ago
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?
- vlovich123 2y ago
  > 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-launch https://www.space.com/spacex-falcon-heavy-europa-clipper-lau...
- Rebelgecko 2y ago
  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.
d_silin 2y ago
Damn, I am impressed how nonchalantly the flagship NASA mission was using the reused boosters, dirty from soot.
- grecy 2y ago
  NASA prefer them now, as they're "flight proven". They're using them to launch astronauts now too.
- ballooney 2y ago
  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.
- deleted 2y ago
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- mmooss 2y ago
  Agreed. And they said that the (second?) stage was the same one that failed to ignite on a prior mission. How does the NASA administrator sleep at night with everyone's careers, the agency's reputation and funding, the future of planetary bioscience, research by so many scientists, all depending on that stage? (What's the most valuable payload NASA has lost during launch? Apollo 1 wasn't launching, nor were the space shuttles.)
  - oceanplexian 2y ago
    A used booster is probably more reliable than a new one. I know aircraft engines have a bathtub curve, perhaps reusable rockets work the same way.
  - darknavi 2y ago
    Falcon 9 second stages are not re-usable, so not sure what you mean. Maybe they meant that it's the same model? As for the first stage boosters, they have a proven reliable record with re-usability.
proee 2y ago
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?
- dgrin91 2y ago
  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
- hydrogen7800 2y ago
  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.
  - consumer451 2y ago
    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?
    - mandevil 2y ago
      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.
frinxor 2y ago
https://en.wikipedia.org/wiki/Europa_Clipper#Launch_and_trajectory 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
supplemental 2y ago
For a moment I though this is European space agency sending a rocket :'(
mmooss 2y ago
I love JPL's straightforward bio: https://www.nasa.gov/jpl/jet-propulsion-laboratory-history/ 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.)
mmooss 2y ago
I finally have a chance to watch now ... On NASA's broadcast someone says, 'we believe ocean worlds are the most common type of planetary body in the universe.' That surprises to me due to the lack of atmosphere on most bodies, the lack of liquid and moisture in space, the prevelance of gas giants, etc. How does that come to be true? Possibly, speaking live, they omitted some qualification and it's not literally true. Also, looking at the rocket, I wondered about their optimized forms. We're accustomed to their appearance, but why not an even smaller 'forward' (i.e., direction of flight) cross-section? Most of the air resistance has to be on forward-facing surfaces. The rocket might need to be taller for fuel capacity, but so what? ... My question really is, what limits reducing the cross-section? An engine component? Vertical height for some reason? I'm assuming air resistance has a major impact on speed and fuel consumption, but maybe it's just not that important?
- icegreentea2 2y ago
  Air resistance matters, but is only one factor. A much more major factor that a rocket needs to overcome is just gravity - ie marginal mass considerations generally trump marginal aerodynamic considerations. Partly this is a result of engineers having much more ability to control the effects of aerodynamics through launch trajectory/profile design (since aero forces can be controlled by through controlling velocity and altitude, while gravity... much less control). Here are some factors to consider that generally trend against just "increasing the fineness ratio". Consider your fuel tanks. Assuming that you have liquid fuel, the static pressure at the bottom of the tank for a given fuel and gravity is purely a function of the height of the fuel column. This means that the taller your fuel tank, the stronger the tank needs to be (at the bottom) to contain it. This will tend to increase your non-payload, non-fuel mass - this is bad. Similarly, as your rocket gets taller and taller, there is more and more structural mass sitting on top that needs to be supported - ie you need stronger structures. When a rocket second stage is in vacuum, all of the sudden you want the largest possible nozzle you can get to get the most thrust out of your exhaust. Now having a larger diameter to work with is useful since it's now easier and simpler to have a large diameter nozzle. Rockets exist to launch payload, which often cannot be shrunk below specific sizes and/or have difficulty being mounted in different orientation. The uh... extra phallic shape of the Falcon Heavy in this case is because the payload fairing needs to be large enough to encapsulate the payload. It's not possible (or really useful) to shrink rocket diameters much smaller than their expected payload. For a size comparison, the Falcon Heavy's payload fairing is 5.2m in diameter. This isn't particularly a small space, but it's not particularly large either - it's basically exactly the length of a F-150 or two sheets of plywood/drywall stacked lengthwise.
consumer451 2y ago
Alternate streams with commentary... Everyday Astronaut: https://www.youtube.com/watch?v=IAixoyE78rE https://www.youtube.com/watch?v=IAixoyE78rE NASA Spaceflight: https://www.youtube.com/watch?v=9JUn8LmGYEA https://www.youtube.com/watch?v=9JUn8LmGYEA (This is not an official NASA stream)
- p1mrx 2y ago
  Spaceflight Now: https://www.youtube.com/watch?v=tZjszhRVo9s https://www.youtube.com/watch?v=tZjszhRVo9s
- whitehexagon 2y ago
  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.
  - ahazred8ta 2y ago
    There's an economics 404 too: https://www.ft.com/404#humor https://www.ft.com/404#humor * Moral Hazard: Showing you this page would only encourage you to want more pages. * Theory of the second best: The best outcome was unachievable, so you have arrived here instead.
- diggan 2y ago
  And for people who prefer text: https://www.washingtonpost.com/science/2024/10/14/europa-clipper-jupiter-moon-launch/ https://www.washingtonpost.com/science/2024/10/14/europa-cli...
  - ralfd 2y ago
    > 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!
    - 2y ago
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218 points by belter 2y ago

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sidcool 2y ago

Are the side boosters going to be recovered?

ceejayoz 2y ago
No. All cores expended in this launch.
benjismith 2y ago
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!
- linotype 2y ago
  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?
  - malfist 2y ago
    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
  - alfiopuglisi 2y ago
    It's a limitation of the Falcon Heavy, the launcher used this time. A future, more powerful one could do it while being reusable.
    - tsimionescu 2y ago
      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.
      - dotnet00 2y ago
        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.
  - tsimionescu 2y ago
    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.
  - perihelions 2y ago
    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 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)
    - whamlastxmas 2y ago
      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
  - mmooss 2y ago
    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.
  - ls612 2y ago
    They traded off the expense of expending a whole Falcon Heavy against the benefit of having additional delta-V to get to Jupiter faster.
  - stetrain 2y ago
    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.
  - panick21_ 2y ago
    You just go to distributed launch. You launch a rocket multiple times, fuel up and use that to escape. If you use your upper stage as the primary, its unlikely to ever come back. But in future you would potentially have special boost stage for that. See something like Impulse Space is building. But for these really powerful throws, its probably just cheaper to just drop an upper stage. Upper stages are a drop in the bucket compared to the cost of a flagship mission. A Falcon 9 upper stage is only a couple million $.
pedrosbmartins 2y ago
Not this time, only the payload fairing.
- bryanlarsen 2y ago
  It's wild that the only thing they recover is the last thing they jettison!
  - SonicScrub 2y ago
    Lightweight enough to be recovered via parachute system, unlike the big heavy boosters which need thrust!
wlesieutre 2y ago
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-manager-gives-go-for-launch/ https://blogs.nasa.gov/europaclipper/2024/10/14/nasa-launch-...
- imglorp 2y ago
  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.
  - wolf550e 2y ago
    They also removed the gridfins and their engines. https://blogs.nasa.gov/europaclipper/wp-content/uploads/sites/378/2024/10/Europa_vertical_sunrise_101324_DSC_7128.jpg https://blogs.nasa.gov/europaclipper/wp-content/uploads/site...
moffkalast 2y ago
The suspiciously clean white areas on all three boosters where the landing legs have been removed are good indicators of what's planned.

throw0101c 2y ago

Veritasium video on the Clipper probe/mission: * https://www.youtube.com/watch?v=DJO_9auJhJQ https://www.youtube.com/watch?v=DJO_9auJhJQ Real Engineering: * https://www.youtube.com/watch?v=SzKkBOUvsAY 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 https://en.wikipedia.org/wiki/Clipper

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stoneman24 2y ago
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.

payamb 2y ago

ATTEMPT NO LANDING THERE.

imzadi 2y ago
They haven't given me my monolith, so no contract established

DiscourseFan 2y ago

can't wait to try some tasty Europafish

mmooss 2y ago

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?

vlovich123 2y ago
> 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-launch https://www.space.com/spacex-falcon-heavy-europa-clipper-lau...
Rebelgecko 2y ago
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.

d_silin 2y ago

Damn, I am impressed how nonchalantly the flagship NASA mission was using the reused boosters, dirty from soot.

grecy 2y ago
NASA prefer them now, as they're "flight proven". They're using them to launch astronauts now too.
ballooney 2y ago
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.
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mmooss 2y ago
Agreed. And they said that the (second?) stage was the same one that failed to ignite on a prior mission. How does the NASA administrator sleep at night with everyone's careers, the agency's reputation and funding, the future of planetary bioscience, research by so many scientists, all depending on that stage? (What's the most valuable payload NASA has lost during launch? Apollo 1 wasn't launching, nor were the space shuttles.)
- oceanplexian 2y ago
  A used booster is probably more reliable than a new one. I know aircraft engines have a bathtub curve, perhaps reusable rockets work the same way.
- darknavi 2y ago
  Falcon 9 second stages are not re-usable, so not sure what you mean. Maybe they meant that it's the same model? As for the first stage boosters, they have a proven reliable record with re-usability.

proee 2y ago

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?

dgrin91 2y ago
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
hydrogen7800 2y ago
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.
- consumer451 2y ago
  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?
  - mandevil 2y ago
    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.

frinxor 2y ago

https://en.wikipedia.org/wiki/Europa_Clipper#Launch_and_trajectory 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

supplemental 2y ago

For a moment I though this is European space agency sending a rocket :'(

mmooss 2y ago

I love JPL's straightforward bio: https://www.nasa.gov/jpl/jet-propulsion-laboratory-history/ 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.)

mmooss 2y ago

I finally have a chance to watch now ... On NASA's broadcast someone says, 'we believe ocean worlds are the most common type of planetary body in the universe.' That surprises to me due to the lack of atmosphere on most bodies, the lack of liquid and moisture in space, the prevelance of gas giants, etc. How does that come to be true? Possibly, speaking live, they omitted some qualification and it's not literally true. Also, looking at the rocket, I wondered about their optimized forms. We're accustomed to their appearance, but why not an even smaller 'forward' (i.e., direction of flight) cross-section? Most of the air resistance has to be on forward-facing surfaces. The rocket might need to be taller for fuel capacity, but so what? ... My question really is, what limits reducing the cross-section? An engine component? Vertical height for some reason? I'm assuming air resistance has a major impact on speed and fuel consumption, but maybe it's just not that important?

icegreentea2 2y ago
Air resistance matters, but is only one factor. A much more major factor that a rocket needs to overcome is just gravity - ie marginal mass considerations generally trump marginal aerodynamic considerations. Partly this is a result of engineers having much more ability to control the effects of aerodynamics through launch trajectory/profile design (since aero forces can be controlled by through controlling velocity and altitude, while gravity... much less control). Here are some factors to consider that generally trend against just "increasing the fineness ratio". Consider your fuel tanks. Assuming that you have liquid fuel, the static pressure at the bottom of the tank for a given fuel and gravity is purely a function of the height of the fuel column. This means that the taller your fuel tank, the stronger the tank needs to be (at the bottom) to contain it. This will tend to increase your non-payload, non-fuel mass - this is bad. Similarly, as your rocket gets taller and taller, there is more and more structural mass sitting on top that needs to be supported - ie you need stronger structures. When a rocket second stage is in vacuum, all of the sudden you want the largest possible nozzle you can get to get the most thrust out of your exhaust. Now having a larger diameter to work with is useful since it's now easier and simpler to have a large diameter nozzle. Rockets exist to launch payload, which often cannot be shrunk below specific sizes and/or have difficulty being mounted in different orientation. The uh... extra phallic shape of the Falcon Heavy in this case is because the payload fairing needs to be large enough to encapsulate the payload. It's not possible (or really useful) to shrink rocket diameters much smaller than their expected payload. For a size comparison, the Falcon Heavy's payload fairing is 5.2m in diameter. This isn't particularly a small space, but it's not particularly large either - it's basically exactly the length of a F-150 or two sheets of plywood/drywall stacked lengthwise.

consumer451 2y ago

Alternate streams with commentary... Everyday Astronaut: https://www.youtube.com/watch?v=IAixoyE78rE https://www.youtube.com/watch?v=IAixoyE78rE NASA Spaceflight: https://www.youtube.com/watch?v=9JUn8LmGYEA https://www.youtube.com/watch?v=9JUn8LmGYEA (This is not an official NASA stream)

p1mrx 2y ago
Spaceflight Now: https://www.youtube.com/watch?v=tZjszhRVo9s https://www.youtube.com/watch?v=tZjszhRVo9s
whitehexagon 2y ago
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.
- ahazred8ta 2y ago
  There's an economics 404 too: https://www.ft.com/404#humor https://www.ft.com/404#humor * Moral Hazard: Showing you this page would only encourage you to want more pages. * Theory of the second best: The best outcome was unachievable, so you have arrived here instead.
diggan 2y ago
And for people who prefer text: https://www.washingtonpost.com/science/2024/10/14/europa-clipper-jupiter-moon-launch/ https://www.washingtonpost.com/science/2024/10/14/europa-cli...
- ralfd 2y ago
  > 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!
  - 2y ago

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