Man has already sent machines to the Moon or to Mars and even to deep interstellar space. Is it then possible to send a spacecraft to the Sun? The answer is yes and it will be soon.
In 2018, NASA plans to launch the Solar Probe Plus mission to the Sun. The Earth is located about 149 million kilometers from the Sun and Solar Probe Plus is expected to come within about 6 million kilometers of our star. “This will be our first mission to fly to the Sun Eric Christian, NASA researcher at Goddard Space Flight Center, told Live Science. » We can’t get to the very surface of the Sun, but the mission will get close enough to answer three important questions “, he adds.
First, the researchers hope this mission will reveal why the Sun’s surface, called the photosphere, isn’t as hot as the Sun’s atmosphere called the corona. Indeed, the surface of the Sun is at around 5,500 ° C against 2,000,000 ° C in its atmosphere, explains NASA. » You might think that the farther you get from a hot spring, the cooler it gets. “, explains Eric Christian. » Why the atmosphere is hotter than the surface is a big puzzle to solve « .
Next, the researchers want to understand how the solar wind gets its speed. » The Sun blows a stream of charged particles in all directions at around 1.6 million km/h. But we don’t yet know where this acceleration is coming from. “, adds Eric Christian.
Third, the mission must determine why the sun occasionally emits high-energy particles (called solar energetic particles) that pose a hazard to unprotected astronauts and spacecraft. Researchers have tried to figure out these mysteries from Earth, but » the problem is that we are 149 million miles away said Eric Christian. » [La distance fait] that things blur in a way that makes it hard to tell what’s going on in the Sun « .
But approaching 6 million kilometers from our star is a complex challenge, obviously with heat as a major constraint. To cope with the extreme temperatures, NASA scientists designed an 11.4 centimeter thick carbon-composite shield designed to withstand temperatures outside the craft of 1,370°C.
The Solar Probe Plus will also be protected against radiation which can damage the electrical circuits of the probe and in particular its memory.