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NASA spacecraft ‘touches’ the Sun for the first time ever

nature.com

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Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#61

Post by rapnie »

wongarsu wrote: post #57
ordu wrote: post #54

Earlier quoted context omitted.

> if I was in the oven, I'll burn and die there too. Eventually. Not momentarily. It would take you much longer to die in the oven than if you would dive into boiling water. I didn't tried both so I cannot be sure, but I suspect that one can live in a boiling water just for a several seconds, while it is possible to live a few tenths of seconds in the oven.

Finnish saunas regularly go to 100°C (210F). I can personally attest that fifteen minutes in dry 100°C air is very survivable, you just get sweaty. Meanwhile 100°C water burns you almost instantly. Though it's worth noting that when talking about humans in air the humidity plays a huge role. Sweat cools your body through evaporative cooling, which works better the drier the air is. At 100% relative humidity you can't…

Yes, some sauna's need you to wear the key of your dressing locker on an arm bracelet. While relaxing nicely in the heat you can instantly burn yourself severely the moment the iron part of the key presses into your skin. (Talking from experience here)

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#62

Post by nine_k »

kwhitefoot wrote: post #22
steventharlow wrote: post #13

Earlier quoted context omitted.

For one, the NASA article says 5 million miles (12 solar radii), not kilometers. So it's actually about 2/3 the quoted number.

Doesn't NASA have some sort of educational duty? Surely they should be using SI units always so as to avoid exactly this kind of confusion.

I'd rather have them always use both units, so that people would eventually learn intuitively, by example, what a km is relayed to a mile, or a kg to a pound, etc.

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#63

Post by dr_dshiv »

Cthulhu_ wrote: post #40
ragebol wrote: post #39

Earlier quoted context omitted.

Putting your head in a hot oven continuously will probably prevent you from dying of the coronavirus indeed.

As does flying to the sun, for that matter. Can't catch corona if you're ~150 million kilometers away from the nearest other person.

Corona is dangerous.

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#64

Post by marcodiego »

remarkEon wrote: post #9

Since getting that close takes a lot of DeltaV and I was curious: >The Parker Solar Probe mission design uses repeated gravity assists at Venus to incrementally decrease its orbital perihelion to achieve a final altitude (above the surface) of approximately 8.5 solar radii, or about 6×106 km (3.7×106 mi; 0.040 au).[35] The spacecraft trajectory will include seven Venus flybys over nearly seven years to gradually shri…

> 6×106 km

Please... 6×10^6 km

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#65

Post by aydwi »

parksy wrote: post #31

This is awesome, the engineering and execution is simply inspiring.

Truly!

The NASA article on the probe mentions its autonomous course corrections abilities. Does anyone have an idea about what kind of onboard CPUs/SoCs do probes like this employ? Which ISAs? How about other hardware like memory and storage? And what kind of programming languages are used to code such internal "systems".

I'm very curious to see if someone can shed some more light on this.

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#66

Post by cecilpl2 »

mcv wrote: post #27
bisRepetita wrote: post #23

For metric system people, if the Sun and the Earth were 1 meter apart, the probe would get as close as 11cm from the Sun. (site writes: "If Earth was at one end of a yard-stick and the Sun on the other, Parker Solar Probe will make it to within four inches of the solar surface.")

But that's not really touching the sun, is it?

The sun doesn't have a solid surface like the Earth - it is a ball of gas that gets progressively less dense as it transitions to vacuum.

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#67

Post by spookthesunset »

bisRepetita wrote: post #23

For metric system people, if the Sun and the Earth were 1 meter apart, the probe would get as close as 11cm from the Sun. (site writes: "If Earth was at one end of a yard-stick and the Sun on the other, Parker Solar Probe will make it to within four inches of the solar surface.")

11cm is still a long ways away. It's crazy how close yet so far everything is.

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#68

Post by [deleted] »

dmurray wrote: post #35
remarkEon wrote: post #9

Since getting that close takes a lot of DeltaV and I was curious: >The Parker Solar Probe mission design uses repeated gravity assists at Venus to incrementally decrease its orbital perihelion to achieve a final altitude (above the surface) of approximately 8.5 solar radii, or about 6×106 km (3.7×106 mi; 0.040 au).[35] The spacecraft trajectory will include seven Venus flybys over nearly seven years to gradually shri…

Highly elliptical orbits are cheaper to achieve anyway, right? You can get into one directly from your Venus gravity assists, and not have to keep precious fuel to transfer to a circular orbit later on.

[deleted]

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#69

Post by dr_dshiv »

dr_dshiv wrote: post #63
Cthulhu_ wrote: post #40

Earlier quoted context omitted.

As does flying to the sun, for that matter. Can't catch corona if you're ~150 million kilometers away from the nearest other person.

Corona is dangerous.

I can’t believe you want to make light of it!

Re: NASA spacecraft ‘touches’ the Sun for the first time ever

#70

Post by [deleted] »

Aachen wrote: post #37
threefour wrote: post #5

If you’re curious why it won’t melt: https://www.nasa.gov/feature/goddard/2018/traveling-to-the-s...

Relevant part: the capturing cups are of metals with high melting points, plus > The corona through which Parker Solar Probe flies, for example, has an extremely high temperature but very low density. Think of the difference between putting your hand in a hot oven versus putting it in a pot of boiling water And for the rest of the craft there is a highly reflective heat shield.

[deleted]
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