Parker signal gets back at 05:00 GMT on the 28th!
Probing atmosphere of sun by flying through it. It’s at a distance of 0.04AU, which is the closent we’ve ever gotten to the sun. It’s 1,400C.
Open question: why corona is so hot. The sun’s surface/equilibrium temperature is “only 6,000C”, but the corona can reach millions of degrees.
The corona is the outer part of the sun’s atmosphere, the part that’s visible during eclipses.
Has 115mm thick carbon-composite shielding.