NASA - Europa Clipper updates and discussion

[Blackstar]

so a female lead's pet project getting canceled

"Pet project" is a really bad characterization. She was an instrument principal investigator. Don't trivialize this stuff.

[Blackstar]

What makes the mission so expensive?

Radiation.

Plus complexity.

But certainly radiation.

[redliox]

so a female lead's pet project getting canceled

"Pet project" is a really bad characterization. She was an instrument principal investigator. Don't trivialize this stuff.

Meant to imply "of personal significance", not trivial.

The idea good, hardware and funding perhaps less so.

[vjkane]

I recall "The Mission" book touching upon sexism as concerning within JPL...so a female lead's pet project getting canceled in an "old boy's club" would look bad.

I have a number of women colleagues and students. I know that sexism, often blatant, continues to be a serious problem in the sciences. We need to expose it, and make that that we do not further propagate it.

[redliox]

The 'Clipper's cost has apparently been raised by around $700 million.  While this seems to be related to handling pandemic stuff and the usual cost inflation...is there any positive spin to this?  Aside from, naturally, just keeping the mission running?...

[VSECOTSPE]

The 'Clipper's cost has apparently been raised by around $700 million.  While this seems to be related to handling pandemic stuff and the usual cost inflation...is there any positive spin to this?  Aside from, naturally, just keeping the mission running?...

A lot of it seems driven by Phase E — operations and science — underfunding.  That’s an unforced error.  Budgeting for ops teams, science teams, and data analysis should be straightforward.

The silver lining is that Phase E issues don’t portend Phase D issues — development — when the marching army and big money are being deployed and hiccups can snowball into major delays/overruns/terminations.  I have to give credit to Zurbuchen and his team for jumping on the one substantial issue they’ve had so far with the radiometer a year or so ago.

The other silver lining is that you’re spending on actually getting science and greater understanding of Europa, not just fixing an engineering foul-up.

[Blackstar]

A lot of it seems driven by Phase E — operations and science — underfunding.  That’s an unforced error.  Budgeting for ops teams, science teams, and data analysis should be straightforward.

The silver lining is that Phase E issues don’t portend Phase D issues — development — when the marching army and big money are being deployed and hiccups can snowball into major delays/overruns/terminations.  I have to give credit to Zurbuchen and his team for jumping on the one substantial issue they’ve had so far with the radiometer a year or so ago.

The other silver lining is that you’re spending on actually getting science and greater understanding of Europa, not just fixing an engineering foul-up.

So my guess--and I don't have any evidence of this--is that they looked at the budget again and decided that they were underfunding the Phase E compared to what this mission is supposed to do. So they added in that Phase E money to make sure they are covered. It's not a sign of something going wrong with the mission development, it's a reassessment of how much they should properly spend on science.

And the alternative would be to under-fund that science and not get the full value of the mission. (Or presumably, the other alternative would be to add in that Phase E money later in the mission, which is probably not an efficient way to do things.)

I would add that in the past, NASA has played games with the budgets using Phase E money. I think that to cover an overrun on Perseverance before launch, they borrowed money from the Phase E budget, figuring that they would add it in again later. It sounds like they are taking a more responsible approach this time.

[ccdengr]

What makes the mission so expensive?

Radiation.

The Clipper multiple-flyby concept was originally proposed as a lower-radiation-dose alternative to Europa Orbiter.  But the desire for more science drove up the number of flybys and the dose kept increasing, and the new technologies for rad-hardness discussed for EO mostly never materialized.  The cost snowballed to the point that Clipper will end up costing as much or more than EO was supposed to cost.

[Blackstar]

What makes the mission so expensive?

Radiation.

The Clipper multiple-flyby concept was originally proposed as a lower-radiation-dose alternative to Europa Orbiter.  But the desire for more science drove up the number of flybys and the dose kept increasing, and the new technologies for rad-hardness discussed for EO mostly never materialized.  The cost snowballed to the point that Clipper will end up costing as much or more than EO was supposed to cost.

You clipped out the part where I wrote "complexity."

[skizzo]

https://www.reuters.com/lifestyle/science/europas-similarity-greenland-hints-that-jupiter-moon-could-harbor-life-2022-04-19/

[deadman1204]

https://www.reuters.com/lifestyle/science/europas-similarity-greenland-hints-that-jupiter-moon-could-harbor-life-2022-04-19/

Gotta love those miss-leading titles heh. "Hints that it harbors life", not "hints that it might have conditions to allow life".

Unlike Enceladus, Europa has the potentially fatal flaw of the water layer being too deep. Its quite possible there are several miles of ice at the bottom of its ocean, which means zero contact with rock - hence no minerals available.

[Star One]

This new paper seems relevant to this thread, it also contradicts the speculation of the post above and suggests that shallow water maybe ubiquitous across the moon.

Double ridge formation over shallow water sills on Jupiter’s moon Europa

Abstract
Jupiter’s moon Europa is a prime candidate for extraterrestrial habitability in our solar system. The surface landforms of its ice shell express the subsurface structure, dynamics, and exchange governing this potential. Double ridges are the most common surface feature on Europa and occur across every sector of the moon, but their formation is poorly understood, with current hypotheses providing competing and incomplete mechanisms for the development of their distinct morphology. Here we present the discovery and analysis of a double ridge in Northwest Greenland with the same gravity-scaled geometry as those found on Europa. Using surface elevation and radar sounding data, we show that this double ridge was formed by successive refreezing, pressurization, and fracture of a shallow water sill within the ice sheet. If the same process is responsible for Europa’s double ridges, our results suggest that shallow liquid water is spatially and temporally ubiquitous across Europa’s ice shell.

https://www.nature.com/articles/s41467-022-29458-3

[deadman1204]

This new paper seems relevant to this thread, it also contradicts the speculation of the post above and suggests that shallow water maybe ubiquitous across the moon.

There is no contradiction here. The ice layer at the BOTTOM of enceledus's ocean would exist due to pressure, not freezing temperatures. I agree it seems quite likely for there to be an ocean (even a global one) on the moon. However, the extreme depth of that ocean seems to imply miles of ice at the bottom caused by the high pressures.

[Conexion Espacial]

https://twitter.com/bobbybraun/status/1532037752858058752

[Conexion Espacial]

The agency’s mission to explore Jupiter’s icy moon takes a big step forward as engineers deliver a major component of the spacecraft.


The main body of NASA’s Europa Clipper spacecraft has been delivered to the agency’s Jet Propulsion Laboratory in Southern California. Over the next two years there, engineers and technicians will finish assembling the craft by hand before testing it to make sure it can withstand the journey to Jupiter’s icy moon Europa.


The spacecraft body is the mission’s workhorse. Standing 10 feet (3 meters) tall and 5 feet (1.5 meters) wide, it’s an aluminum cylinder integrated with electronics, radios, thermal loop tubing, cabling, and the propulsion system. With its solar arrays and other deployable equipment stowed for launch, Europa Clipper will be as large as an SUV; when extended, the solar arrays make the craft the size of a basketball court. It is the largest NASA spacecraft ever developed for a planetary mission.


“It’s an exciting time for the whole project team and a huge milestone,” said Jordan Evans, the mission’s project manager at JPL. “This delivery brings us one step closer to launch and the Europa Clipper science investigation.”


Set to launch in October 2024, Europa Clipper will conduct nearly 50 flybys of Europa, which scientists are confident harbors an internal ocean containing twice as much water as Earth’s oceans combined. And the ocean may currently have conditions suitable for supporting life. The spacecraft’s nine science instruments will gather data on Europa’s atmosphere, surface, and interior – information that scientists will use to gauge the depth and salinity of the ocean, the thickness of the ice crust, and potential plumes that may be venting subsurface water into space.



Those instruments already have begun arriving at JPL, where the phase known as assembly, test, and launch operations has been underway since March. The ultraviolet spectrograph, called Europa-UVS, arrived in March. Next came the spacecraft’s thermal emission imaging instrument, E-THEMIS, delivered by the scientists and engineers leading its development at Arizona State University. E-THEMIS is a sophisticated infrared camera designed to map Europa’s temperatures and help scientists find clues about the moon’s geological activity – including regions where liquid water may be near the surface.


By the end of 2022, most of the flight hardware and the remainder of the science instruments are expected to be complete.


The Whole Package


The Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, designed Europa Clipper’s body in collaboration with JPL and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The flight system designed, built, and tested by APL – using a team of hundreds of engineers and technicians – was the physically largest system ever built by APL,” said APL’s Tom Magner, the mission’s assistant project manager.....


More details: https://www.jpl.nasa.gov/news/nasas-europa-clipper-mission-completes-main-body-of-the-spacecraft

[redliox]

Space.com just did an article. The biggest take aways were about reducing the number of flybys from 53 to 49 and considering a Ganymede or possibly Callisto impact at end of mission. Was there a recent OPAG meeting mentioning this as well?

[Blackstar]

Space.com just did an article. The biggest take aways were about reducing the number of flybys from 53 to 49 and considering a Ganymede or possibly Callisto impact at end of mission. Was there a recent OPAG meeting mentioning this as well?

At OPAG there was discussion of doing a Ganymede impact for Juno. I don't know what was said about EC. Maybe they've discovered that it uses less fuel to maneuver to hit Ganymede than to fly into Jupiter, and so that is the preferred solution to ending a mission.

[redliox]

An Io impact would seem more prudent to me, but I could see how Ganymede is more fuel efficient.

[deadman1204]

Is reducing the number of orbits just magic tricks for the budget? Doesn't that just make the primary mission shorter, and then the first extended mission starts right afterwards? So over the span of time nothing actually is different?

[ccdengr]

Is reducing the number of orbits just magic tricks for the budget?

AFAIK, yes.  And then they'll almost certainly get added back in as an extended mission if the s/c is still healthy.