NASA is working on a plan to launch a mission to visit and study the sun closer than ever before, China's Xinhua news agency quoted the Jet Propulstion Laboratory (JPL) as saying.

The unprecedented project named Solar Probe Plus, is slated to launch no later than 2018.

The small car-sized spacecraft will plunge directly into the sun's atmosphere approximately 6.4 million kilometers (four million miles) from our star's surface, the JPL said.

The spacecraft will explore a region no other spacecraft ever has encountered, said the JPL, headquartered in Pasadena, Los Angeles.

As the spacecraft approaches the sun, its revolutionary carbon- composite heat shield must withstand temperatures exceeding about 1, 400 degrees Celsius (2,550 degrees Fahrenheit) and blasts of intense radiation, the JPL said on its Web.

The spacecraft will have an up-close and personal view of the sun, enabling scientists to better understand, characterize and forecast the radiation environment for future space explorers, according to the JPL.

"The experiments selected for Solar Probe Plus are specifically designed to solve two key questions of solar physics -- why is the sun's outer atmosphere so much hotter than the sun's visible surface and what propels the solar wind that affects Earth and our solar system? " said Dick Fisher, director of NASA's Heliophysics Division in Washington.

"We've been struggling with these questions for decades and this mission should finally provide those answers."

NASA has selected five science investigations that will unlock the sun's biggest mysteries, including one led by a scientist from NASA's JPL.

In 2009, NASA invited researchers to submit science proposals. Thirteen were reviewed by a panel of NASA and outside scientists. The total dollar amount for the five selected investigations is approximately US$180 million for preliminary analysis, design, development and tests.

Source : Bernama / Xinhua