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Solar Orbiter first images revealed

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Re: Solar Orbiter first images revealed

#31

Post by Valgrim »

enriquto wrote: post #30
dylan604 wrote: post #5

Earlier quoted context omitted.

I "hacked" NASA (I used wget/curl to download the publicly available images) to get the specific shots (wavelength/resolution) from SOHO to get an entire 11 day's worth of a single rotation of the sun. We put that sequence into a VR setting. It was strictly for a demo/PoC of an idea we were knocking around. The idea didn't gain any traction with the producers, so it just got shelved. It was fun showing everyone how s…

The data is public and this usage seems to be intended, not sure why you call it "hacking".

Hacking has two meaning: one is to commit a computer crime, the other is to use technical knowledge to overcome a problem. This website name refers to the latter.

Re: Solar Orbiter first images revealed

#34

Post by koheripbal »

mcbits wrote: post #23

I love watching video of activity on the solar surface because my brain has no intuition for the immense gravity and plasma dynamics at play. It's almost like getting a glimpse of a world with different laws of physics.

The surface gravity of the Sun is only about 27x that of Earth (due to its lower density). More, sure, but not so much that you should consider it different physics.

...of course the temperature and hydrogen composition make it pretty different :)

Re: Solar Orbiter first images revealed

#35

Post by zaarn »

sandworm101 wrote: post #24
zaarn wrote: post #17

Earlier quoted context omitted.

The direction is "towards" or "away" from the sun, the only way to get closer to the sun is to make your orbit smaller, the only way to do that is to slow down in your current orbit. You can't reach a lower orbit by accelerating. (I'm simplifying a bit, it's all acceleration, what matters is if it's in your orbital velocity, prograde, or against it, retrograde)

You can accelerate so slow down. The flyby of a planet creates an accelleration that, if in the correct direction, results in a slower orbital velocity in the sun's reference frame. In really simple terms, if you approach the planet from the right (in a counterclockwise solar system) you speed up, if you aim to the left you slow down. The velocity is transferred to/from the planet. https://youtu.be/hKjcbmlAaYY Notice…

Gravitational slingshots are a method were you accelerate and end up slowing down but I don't think it's fair to say that you "just accelerate to reach a lower orbit", since your acceleration ultimately ends up being either retrograde for very low fly-by orbits or on the normal/radial axis. Or possibly even prograde.

Basically, using a flyby to apply retrograde speed is not much more than accelerating prograde and then using the gravity of a planet to A) move your orbital position without a speed change and/or B) redirect your acceleration.

Re: Solar Orbiter first images revealed

#36

Post by jcun4128 »

moritonal wrote: post #21
jcun4128 wrote: post #13

Haha these cookie popups, I don't know why I'm hesitant to take action on them. So like this site on mobile I'll read the article through half my phone screen.

Fun fact, the video changes from a direct video element to a YouTube element if you accept the cookie banner.

That's interesting, just yesterday I considered the idea of the cost(host) to have to download an entire video up front eg. video tag vs. streaming(YouTube) I wonder if that is the rationale.

Re: Solar Orbiter first images revealed

#37

Post by mnw21cam »

lucideer wrote: post #20
sdenton4 wrote: post #4

This is another reminder of just how little space exploration has happened so far... I'm kinda amazed no one's ever just thrown a probe at the sun to get as much data as possible before it burns. I get a similar feeling staring at the bare handful of images from the surface of Venus.

> kinda amazed no one's ever just thrown a probe at the sun [...] before it burns The answer is somewhat simply that it burns real quick. These guys made the heat shield for this thing and have some decent insights: http://enbio.eu/solar-orbiter/

Also, it takes a heck of a lot of rocket fuel to just throw a probe at the Sun. More than to send it out of the solar system.

Re: Solar Orbiter first images revealed

#38

Post by koheripbal »

op03 wrote: post #15
lattalayta wrote: post #9

Earlier quoted context omitted.

Ya, at first glance it seems easier to get to the sun, but due to orbital mechanics it's actually harder than it seems. Probes bound for deep-space destinations like Mars can piggyback off Earth’s momentum to fly faster. For a spacecraft to launch toward the sun, on the other hand, it must accelerate to nearly match the Earth’s velocity—in the opposite direction. With the planet’s motion essentially canceled out, the…

Interesting article thx. I dont get why the speed up works only towards the outer solar system though. Why does it have to loose speed to control direction?

It's all relative. You can use gravity assists to get closer to the sun, but there are a lot more planets above our orbit than below it (and mercury is too small to be useful). ...so timing gravity assisted deceleration orbits is not just hard, but it takes forever and the only reasonable solution is a very eccentric orbit.

Re: Solar Orbiter first images revealed

#39

Post by Certified »

JohannesH wrote: post #33
memorysafety wrote: post #32

What is this thing here? https://i.imgur.com/hxiwfe6.png (around 25%-25% from top left) Looks distinctly not part of the corona, more like a pod of some sorts, and it also jitters around in the video. I'm puzzled!

Maybe damage to the instruments?

It is definitely a spacecraft side instrumentation artifact. Notice how all three of these jiggle the same? https://imgur.com/a/T7jduVG

Re: Solar Orbiter first images revealed

#40

Post by danbr »

Certified wrote: post #39
JohannesH wrote: post #33

Earlier quoted context omitted.

Maybe damage to the instruments?

It is definitely a spacecraft side instrumentation artifact. Notice how all three of these jiggle the same? https://imgur.com/a/T7jduVG

‘"But in fact, it's a sensor defect," he said. "In future processing when we further optimize this, this will be cleaned up and interpolated from nearby pixels. But for the moment, it's still clearly visible."’

https://www.livescience.com/sun-tardigrade-solar-orbiter-ima...

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