Space agency’s probe will fly closer than ever to the Sun

NASA’S new solar spacecraft is so durable that parts of it will circle the Sun until the Solar System ends, billions of years from now, scientists have said.

The US space agency launches its Parker Solar Probe tomorrow and it will go closer to the Sun than any mission before, to unlock the secrets of radioactive storms that threaten Earth.

Earth, and all the other objects in the Solar System, are constantly wading through the solar wind, a stream of high-energy protons and electrons, emanating from the Sun. The storms are so powerful they can knock out satellites, threaten aircraft, disrupt communications and even interfere with electricity supplies.

The probe will orbit the Sun for seven years, about 3.4 million miles from its surface, where temperatures reach 2,552F (1,400C). It relies on a 4.5in (11.4cm) carbon heat shield which is so strong it will last for billions of years, even when the rest of the spacecraft has disintegrated.

Andy Driesman, a probe manager from Johns Hopkins University said: “At four million miles the Sun is very hot, so we need to bring an umbrella with us – a carbon heat shield … and that will be around to the end of the Solar System.”

The spacecraft also holds a memory card containing the names of more than 1.1 million people who were asked to write in to support the mission. Prof Nicky Fox, a London-born project scientist from Johns Hopkins University, said: “I think the spacecraft will break up into parts and form dust, and then those names will orbit the Sun forever.”

The nearest a spacecraft has previously come to the Sun was the Helios 2 mission in 1976, which flew to within 27 million miles.

Prof Mathew Owens, a space scientist at the University of Reading, said: “It’s an incredibly hostile environment in which to do science, so the spacecraft has faced enormous engineering challenges. But everything is looking positive for Saturday.

“The thing we really don’t understand about the Sun, and therefore stars in general, is why its atmosphere gets hotter further away from the heat source. “We’ve been trying to solve this mystery for more than 50 years.”

The mission was named after Eugene Parker, the solar astrophysicist who first discovered the solar wind.

The memory card on board also contains a copy of his first scientific paper outlining his work.