BOULDER- The searing brightness of the sun reaches all the way to Earth, and now, Earth is about to reach back in its own way.

"This is the first time we're going to a star, the way I look at it," said Robert Ergun, a professor of astrophysics at CU Boulder and a principal co-investigator for Solar Probe Plus.

Solar Probe Plus will journey to the sun in 2018, marking the first time a human spacecraft ever visited a star.

"Our sun is the only star we can get to," Ergun said.

During the mission, scientists will get a closer view of solar storms, magnetic fields, plasma and particles emitted by the sun. Those can potentially impact weather and telecommunication satellites orbiting Earth and power grids on the ground.

"Almost all stars emit this tremendous amount of matter into space and it's one of the frontiers we don't really fully understand," Ergun said.

Gaining that understanding, though, requires Solar Probe Plus to be a special spacecraft. The sun's outer atmosphere, the corona, can reach temperatures of 1.7 million degrees Fahrenheit. On its closest approach to the sun's corona, just under four million miles away, the spacecraft will face temperatures of 2,500 degrees Fahrenheit.

"That is a serious engineering challenge because this is something that has not been done before, bringing a spacecraft that close to the sun and how do you survive that is a big question," said David Malaspina, Solar Probe Plus Co-Investigator who is also based at CU Boulder.

To survive it, engineers are building a special carbon polymer heat shield. It will be used in conjunction with cooling radiators, to help protect the science instruments onboard: including a C-U instrument measuring electric and magnetic fields.

"If any part of that spacecraft gets into the sunlight on closest approach — literally, it's toast," Ergun said.

They are major engineering obstacles required to get Solar Probe Plus to one of the unexplored areas of our solar system.

"We're going to one of the last places where a spacecraft has not gone," Malaspina said. "So in that sense, it is very exciting."

On its closest approach to the sun, the spacecraft will be traveling at a half-a-million miles per hour, making it the fastest spacecraft ever. It will not be going anywhere near the speed of light. However, it will be traveling so fast that scientists said that time will move differently for it. Compared to time here on Earth, it will be off by one second every day.

(© 2015 KUSA)