Amazing Parker Solar Probe!:

https://phys.org/news/2021-11-parker-solar-probe-record-setting-sun.html

Fastest moving thing humans ever made, it peaked out at 364,000 miles per hour! 100 miles per second, 160 Km/sec!
Also getting within 5 million miles or 8 million Km of the sun, that works out to getting heat some 2000 X what we get here, about 2 MEGAWATTS per square meter! That takes a bit of insulation and reflectors to keep from frying.

@sonhouse said
https://phys.org/news/2021-11-parker-solar-probe-record-setting-sun.html

Fastest moving thing humans ever made, it peaked out at 364,000 miles per hour! 100 miles per second, 160 Km/sec!
Also getting within 5 million miles or 8 million Km of the sun, that works out to getting heat some 2000 X what we get here, about 2 MEGAWATTS per square meter! That takes a bit of insulation and reflectors to keep from frying.

I once read that good-old-fashioned aluminum is a superb reflector of infrared heat -- far superior to other metals. If they aren't using aluminum shielding they probably came up with something even better.

@bunnyknight
Wonder if gold is better at reflecting IR? Never looked at that spec🙂

@bunnyknight said
I once read that good-old-fashioned aluminum is a superb reflector of infrared heat -- far superior to other metals. If they aren't using aluminum shielding they probably came up with something even better.

Since Aluminium has a rather low melting temperature I think they need something other.

@ponderable said
Since Aluminium has a rather low melting temperature I think they need something other.

But if your shielding gets too hot it would negate the purpose of keeping the probe's innards as cool as possible. In this case heat deflection is always better than heat tolerance.

@sonhouse

Didn't some space shuttle go too close to the sun or something? Or was that a movie?

@Contenchess
You thinking of Icarus? I think this solar probe is the only one to get that close, 5 million miles away and BTW, that works out to 2 MEGAWATTS per square meter of surface they have to get rid of. Here on Earth, we get about a kilowatt per square meter from the sun so 2000 times that heat load, amazing they can do it at all.

There was a Russian Venus probe, you know Venus is near 1000 degrees F on the surface plus an atmosphere of mainly sulfuric acid AND at about 1500 PSI, about the same as inside a nitrogen bottle.
So what they did was wrap copper coils all around the craft and they circulated liquid nitrogen which kept it cool for about 20 minutes, enough to take some great photos of the place, the ONLY photos of the surface.
Talk about hell......

@sonhouse
So if aluminum could reflect 98% of infrared, that 2 MEGAWATTS per square meter of surface should be reduced to 40 KILOWATTS. Still high, but much better.

@bunnyknight
They didn't just use one reflector, they were stacked top one another, 6 or so I think.
That kind of shielding and the fact it is going 100 miles per SECOND limits the amount of time it spends in that super hot environment.