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Re:ESA – Jupiter Icy Moons Explorer: Live Launch by mpweiher on Thursday April 13, 2023 @03:47AM (#35552304)
The Voyagers took advantage of a special constellation that doesn't happen often:

"In the 1960s, mission designers at JPL noted that the next occurrence of a once-every-175-year alignment of the outer planets would happen in the late 1970s. A spacecraft could take advantage of this opportunity to fly by Jupiter and use its gravity to bend its trajectory to visit Saturn, and repeat the process to also visit Uranus, Neptune, and Pluto."

https://www.nasa.gov/feature/45-years-ago-voyager-1-begins-i...

Re:ESA – Jupiter Icy Moons Explorer: Live Launch by perihelions on Thursday April 13, 2023 @04:18AM (#35552493)
That didn't affect the Earth-Jupiter leg, which was direct.
Re:ESA – Jupiter Icy Moons Explorer: Live Launch by GravitasFailure on Thursday April 13, 2023 @05:09AM (#35552863)
If I'm reading the specs correctly the Titan IIIE was a significantly more powerful vehicle than the Ariane 5 while launching a much smaller payload. JUICE also has to be going slow enough to enter orbit without carrying an insane amount of fuel for braking while Voyager just did a flyby.
Re:ESA – Jupiter Icy Moons Explorer: Live Launch by perihelions on Thursday April 13, 2023 @05:29AM (#35553011)
- "Titan IIIE was a significantly more powerful vehicle than the Ariane 5 while launching a much smaller payload"

Yes, with a fourth stage. (I don't think it's particularly that modern rockets can't integrate such a solid-rocket boost stage, but rather there's no payload that needs this).

https://en.wikipedia.org/wiki/Star_(rocket_stage)

- "JUICE also has to be going slow enough to enter orbit without carrying an insane amount of fuel for braking while Voyager just did a flyby"

The flyby speeds are similar; but JUICE takes a time to get to that speed.

It's not really that difficult to capture into Jupiter. Parent's link [3] says it's only 900 m/s for JUICE. Part of the reason is the extremely deep gravity well; and another is that the moons are large enough to give you effective gravity assists, within the orbit of Jupiter.

Re:ESA – Jupiter Icy Moons Explorer: Live Launch by GravitasFailure on Thursday April 13, 2023 @05:38AM (#35553080)
>The flyby speeds are similar; but JUICE takes a time to get to that speed.

Ahhh, that makes sense. Essentially Voyager did do a direct flight while JUICE isn't, instead building speed by doing slingshots off Earth and Venus.

"First, it will do a fly-by of Earth and the Moon, then slingshot around Venus in 2025 before swinging past Earth again in 2029."

https://phys.org/news/2023-04-europe-juice-mission-jupiter-i...

Re:ESA – Jupiter Icy Moons Explorer: Live Launch by raverbashing on Thursday April 13, 2023 @08:11AM (#35554191)
Yes the problem is not only getting to Jupiter, it is stopping once you get there