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Solar Orbiter gets world-first views of the Sun's poles

186 points by sohkamyung - 26 comments
ahmedfromtunis [3 hidden]5 mins ago
I didn't even realize that we've never seen the sun's poles before as I just assumed we already scanned our star many times over.

A nice reminder of how patchy and limited our knowledge is despite the impression of the opposite.

Keep up the great work, humans!

lostlogin [3 hidden]5 mins ago
‘World First’ is a poor choice of words. ‘First Ever’?
riffraff [3 hidden]5 mins ago
well, they are the first time they're seen on this world so I think it's fine.
lionkor [3 hidden]5 mins ago
It's our world's first -- maybe the others already got it.

Or better, "humanity's first".

bravesoul2 [3 hidden]5 mins ago
Happened outside our world though!
throwaway81523 [3 hidden]5 mins ago
There was a previous mission (Ulysses aka International Solar Polar mission) that sent back a lot of data but for whatever reason, they didn't have it send visual images. Big bright ball = no surprise, maybe.
superkuh [3 hidden]5 mins ago
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.

BurningFrog [3 hidden]5 mins ago
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.

widforss [3 hidden]5 mins ago
Wouldn't the tilt affect the gravity assist of Venus?
zamadatix [3 hidden]5 mins ago
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.
widforss [3 hidden]5 mins ago
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.
labster [3 hidden]5 mins ago
Instead of knowing math, they might just ask an LLM to work out the right orbit.
lionkor [3 hidden]5 mins ago
Looks like they dont, seeing how it hasn't crashed and burnt horribly
NooneAtAll3 [3 hidden]5 mins ago
you linked Parker probe, not Solar Orbiter
jbjorge [3 hidden]5 mins ago
"But in the end, it doesn't even matter"
hcarvalhoalves [3 hidden]5 mins ago
I suppose it takes a lot of deltaV to get a stable orbit over the sun poles?
perihelions [3 hidden]5 mins ago
It's doable with gravity assists. Ulysses got up to 79° inclination using a Jupiter flyby.

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

ChocolateGod [3 hidden]5 mins ago
You'd need to completely cancel out the rotation of the solar system, far beyond what we have the technology to do.
sandworm101 [3 hidden]5 mins ago
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.
sandworm101 [3 hidden]5 mins ago
Dambit. No hexagons. I think i might have lost an old bet.
svachalek [3 hidden]5 mins ago
Ha. I wonder what solar scientists were expecting here, how surprising would it have been if the sun did have polygonal storms like the gas giants?
bravesoul2 [3 hidden]5 mins ago
From a simulation? NVidia had come a long way since you made the bet.
sandworm101 [3 hidden]5 mins ago
No. From the realwold cyclonic storms of Saturn and Jupiter that form unnatural-looking polygons at their poles.

https://en.wikipedia.org/wiki/Saturn%27s_hexagon

https://en.wikipedia.org/wiki/Jupiter%27s_South_Pole

bravesoul2 [3 hidden]5 mins ago
That is fascinating. Next bet is if Saturn's hexagon will change into another n-agon in our lifetime. Obviously we'd need a probe to check.
tickerticker [3 hidden]5 mins ago
LOL
colordrops [3 hidden]5 mins ago
I love this, seems so minor if not paying attention but it's absolutely mind blowing. Getting a view we never saw of the life giver, an object that used to be revered as a god, nearly every human alive I history has basked in it's light and heat, and the for the first time we are seeing it in full