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ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

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Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#31

Post by krylon »

drewg123 wrote: post #6

Wow, 11 years to Jupiter. I wish we had better propulsion systems. EDIT: This wasn't meant to disrespect the ESA mission. I'm just sad that the outer planets are years away, rather than the hours, days, weeks or months of science fiction.

I agree, it would be so cool if we could get there in a couple of weeks.

At least once the spacecraft arrives, it will (assuming everything goes well) do some very interesting exploring. So something to look forward to, even if it takes a long time.

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#32

Post by krylon »

dmix wrote: post #2

Has there ever been a major unmanned project like this that blew up on takeoff/failed in orbit in recent years? I was listening to the huge list of gear they put on this thing by a project lead and the years of hard work by scientists and it would have been heartbreaking if it failed catastrophically. https://youtu.be/Ljh2BKdjpmE

IIRC, the USSR had really bad luck with the various probes they sent to Mars. A couple crashed, and I think one or two got off course and were lost.

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#33

Post by eep_social »

twic wrote: post #19
eep_social wrote: post #17

Earlier quoted context omitted.

This was an intentional choice for efficiency and to allow more science at the destination, “the final flyby.. will be 3700 km from Earth in November 2026” [1] Really disappointing that this is top comment tbh. [1] https://sci.esa.int/web/juice/-/58815-juices-journey-to-jupi...

What? How does getting there more slowly mean more science at the destination? And if so, why is Europa Clipper going to get there much faster?

Delta-v is a scarce resource!

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#34

Post by robszumski »

twic wrote: post #18
drewg123 wrote: post #12

Earlier quoted context omitted.

I stand corrected. I erroneously picked up 2034 from the timeline. But the point still stands; 8 years is a depressingly long time. If we base missions on the discoveries of previous missions, there is an 8-year minimum gap between missions. I'm just hoping we find evidence of extraterrestrial life in my lifetime, and at this rate, we'll be cutting it close..

Europa Clipper, which weighs about the same, is planned to make the same trip in five and a half years, and could have done it in less than three if it had launched on SLS: https://en.wikipedia.org/wiki/Europa_Clipper#Launch_and_traj... Ariane 5 is not particularly powerful as interplanetary launchers go.

Tony Bruno of ULA wrote a nice blog related to this recently. Most launchers are optimized for either LEO or the high energy orbits/interplanetary and are not really well suited to the opposite mission. See Figure 1 for a nice graphic.

https://medium.com/@ToryBrunoULA/the-secrets-of-rocket-desig...

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#35

Post by jmyeet »

I'm glad to see this flagship interplanetary probes launch. For those wondering why it's taking 8 years, it's huge (~6 tons IIRC).

I still hope to see probes enter orbit around Uranus and Neptune in my lifetime. Neptune in particular would be a massive challenge with an expected flight time of ~30 years IIRC so I don't see that happening anytime soon.

The last (and only!) time we've been to Uranus and Neptune is with Voyager 2 in flybys in 1986 and 1989 (respectively). Imagine what we can do with current technology. I guess a flyby is the most we can hope for. Still, I can dream.

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#36

Post by dmix »

krylon wrote: post #32
dmix wrote: post #2

Has there ever been a major unmanned project like this that blew up on takeoff/failed in orbit in recent years? I was listening to the huge list of gear they put on this thing by a project lead and the years of hard work by scientists and it would have been heartbreaking if it failed catastrophically. https://youtu.be/Ljh2BKdjpmE

IIRC, the USSR had really bad luck with the various probes they sent to Mars. A couple crashed, and I think one or two got off course and were lost.

Idk about Mars but that was definitely the experience on Venus (which was far more understandable since they were sending metal balls that would be crushed under pressure within minutes). Only survived about 2-3/10.

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#37

Post by zabzonk »

jmyeet wrote: post #35

I'm glad to see this flagship interplanetary probes launch. For those wondering why it's taking 8 years, it's huge (~6 tons IIRC). I still hope to see probes enter orbit around Uranus and Neptune in my lifetime. Neptune in particular would be a massive challenge with an expected flight time of ~30 years IIRC so I don't see that happening anytime soon. The last (and only!) time we've been to Uranus and Neptune is with…

launch technology (rockets) have not changed much, though certainly sensors have improved a lot. i would love to have more information about the outer planets. but here is my solution to the fermi paradox - it is too bloody hard!

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#38

Post by pkaye »

ChuckMcM wrote: post #4
dmix wrote: post #2

Has there ever been a major unmanned project like this that blew up on takeoff/failed in orbit in recent years? I was listening to the huge list of gear they put on this thing by a project lead and the years of hard work by scientists and it would have been heartbreaking if it failed catastrophically. https://youtu.be/Ljh2BKdjpmE

A good summary of NASA's robotic mission failures: https://astronomy.com/news/2020/12/nasas-failures-robotic-sp... mostly early ones as NASA developed a better process and understanding for getting things right the first time.

YouTube JPL channel has a whole series of videos on all the major robotic missions and their engineering challenges.

https://www.youtube.com/playlist?list=PLTiv_XWHnOZqFnWQs393R...

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#39

Post by throwaway8503 »

drewg123 wrote: post #12
huhtenberg wrote: post #9

Earlier quoted context omitted.

8 years, not 11. > Arrival at Jupiter - July 2031 https://www.esa.int/var/esa/storage/images/esa_multimedia/im...

I stand corrected. I erroneously picked up 2034 from the timeline. But the point still stands; 8 years is a depressingly long time. If we base missions on the discoveries of previous missions, there is an 8-year minimum gap between missions. I'm just hoping we find evidence of extraterrestrial life in my lifetime, and at this rate, we'll be cutting it close..

The impact the time cost has on careers is significant. From what I've heard through science media, it's not uncommon for planetary scientists to spend half or an entire career on a single mission to the outer planets.

Re: ESA’s Juice lifts off on quest to discover secrets of Jupiter’s icy moons

#40

Post by ceejayoz »

sfifs wrote: post #27
867-5309 wrote: post #8

Earlier quoted context omitted.

it's a shame nuclear detonations in space are banned (for obvious reasons)

What is actually the obvious reason to ban nuclear detonation in space (Not planetside) other than proliferation & security concerns?

Geopolitically destabilizing. Nuclear weapons in space can become nuclear weapons not in space very quickly, which makes for itchy trigger fingers.

ICBMs can be detected at launch, so you have 15 minutes to react. Not much, but better than orbital nukes hanging over your head.

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