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Comment by superkuh | Hacker News Reader

This slightly tilted view of the poles is a teaser. I didn't know they'd managed to incorporate late in the mission gravity assists into the cheaper plan B to slightly tweak out of the ecliptic while dropping close to the sun. That's pretty cool. https://upload.wikimedia.org/wikipedia/commons/6/66/Animatio...

But we could've had so much more. The original proposal A for the ESA Solar Orbiter was a highly inclined orbit relative to the ecliptic plane to truly get full polar views of the sun. But this was too expensive. So they went with the cheaper proposal B which was mostly just a spectroscopic platform. Similar to SDO AIA, except in a solar orbit (almost completely within the ecliptic plane) instead of SDO AIA's Earth based sun synchronous orbit.

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They plan to get a more polar orbit each time they get close to Venus: https://www.esa.int/ESA_Multimedia/Images/2020/01/Solar_Orbi...

Not sure if 33° angle in 2029 is the final "polarity" or if they'll keep tilting after that.

Wouldn't the tilt affect the gravity assist of Venus?

The planning of sure, you've gotta make sure you're crossing the plane at the time, but gravity assist itself is otherwise the same though.

At the time, every time, and the position of Venus changes with every orbit. But I guess the folks at ESA are proficient in math.

I suppose it takes a lot of deltaV to get a stable orbit over the sun poles?

You'd need to completely cancel out the rotation of the solar system, far beyond what we have the technology to do.

It's doable with gravity assists. Ulysses got up to 79° inclination using a Jupiter flyby.

https://en.wikipedia.org/wiki/Ulysses_(spacecraft)

It does, but most of the needed dV is harvested from the planets during gravity assists. The probe is accelerated/turned several hundred or thousand m/s and in exchange the planets it passes are shifted/slowed/turned by maybe 0.00000000000000000000001 m/s. In this case, the probe largely needs to slow down, to bleed of the speed it got from being at earth's orbit, so the planets are probably being accelerated.

you linked Parker probe, not Solar Orbiter

"But in the end, it doesn't even matter"

Huh, yeah, I am not entirely sure how that happened. I think copy buffer hijinks. How embarassing. https://upload.wikimedia.org/wikipedia/commons/2/23/Animatio...

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