NASA probe "touches" the sun - and will not melt
Source: NASA Goddard / YouTube
This is absolutely awesome!
Literally in a few weeks, NASA is about to launch into space one of its most ambitious missions. Solar probe Parker will make several "dives" to the surface of the Sun, to practically "touch" it, and will thus be closer to our star than anyone before.
The three lowest orbits of Parker pass at an altitude of about 6.1 million kilometers above the surface, inside the solar corona, where the temperature reaches a million degrees Celsius .
It is clear that the need protection, and it is, pretty cleverly arranged. But we will return to this a little later, but for now - let's talk about the burning heat.
It is difficult to imagine how it is possible to be protected in such conditions at all - because the temperature of only 460 degrees Celsius on Venus quickly led to the failure of electronic equipment on Soviet AMC in the eighties.
But NASA explains to us that there is a nuance between the actual temperature of the object and thermal radiation, since this greatly affects the transfer of heat in space. Temperature characterizes how much speed — and accordingly, energy — a particle has, and thermal radiation — how much energy it actually transfers. In space, particles can move at high speed, but they don’t transfer as much energy as there are not so many.
“Parker will repeatedly pass through the corona, which despite its high temperature has a rather low density,” says Susan Darling“It’s quite simple to imagine using the example of an oven and a saucepan with boiling water — in the oven you can hold out your hand much longer because the air is less dense than water. Accordingly, in comparison with the surface of the Sun itself, in the corona the probe will collide with a smaller number of particles and heat up less. ”
What does this mean for thermal protection? The fact that it will have to withstand a temperature of about 1370 degrees Celsius to protect the contents.
This can only be achieved with amazing technology.. The probe shield is a kind of “sandwich” of two overheated carbon-carbon composite plates, between which there are 11.5 centimeters of carbon foam 2.4 meters in diameter and with a total weight of only 72.5 kilograms. The side directed to the Sun is painted white with ceramics-based paint to reflect the maximum amount of thermal radiation.
And what is striking - the temperature behind the shield will be only 30 degrees Celsius.
All tools that will be located outside the protected area are made of refractory materials. For example, the Faraday cylinder , with which the device will determine the charge and intensity of the solar wind, is made of a titanium-zirconium-molybdenum alloy (melting point about 2350 degrees Celsius), electrostatic plates are made of tungsten (3422 degrees), and all wiring will be made of niobium (2477 degrees).
Of course, Parker will maintain orientation in space in such a way that more sensitive equipment will not be hit by sizzling sunlight, and the solar panels will be hidden behind the shield to avoid overheating on too “hot” trajectories. Additionally, the probe is equipped with a liquid cooling system with deionized water.
Undoubtedly, there are a lot of other unusual engineering solutions in the “stuffing” of the device. Well, we can’t wait to see what new data Parker will bring us about the Sun, its crazy atmosphere and mad “winds”.