NASA plans to send its first robotic spacecraft to the Sun next year that is slated to get within six million kilometres of the blazing star to probe its atmosphere. Humans have sent spacecraft to the Moon, Mars and even distant interstellar space. Now, NASA plans to launch the Solar Probe Plus mission to the Sun which is about 149 million kilometres from the Earth. We can’t get to the very surface of the Sun,” but the mission will get close enough to answer three important questions, Christian said. First, the mission will hopefully unveil why the surface of the Sun, called the photosphere, is not as hot as its atmosphere, called the corona. First, the mission will hopefully unveil why the surface of the Sun, called the photosphere, is not as hot as its atmosphere, called the corona.According to NASA, the surface temperature of the Sun is only about 5,500 degrees Celsius. However, the atmosphere above it is a sizzling two million degrees Celsius. The mission may also ascertain why the Sun occasionally emits high-energy particles that are a danger to unprotected astronauts and spacecraft. NASA has designed a 11.4 centimetres carbon-composite shield, which is designed to withstand temperatures outside the spacecraft of 1,370 degrees Celsius. According to Eric Christian, a NASA research scientist at the Goddard Space Flight Centre, though the spacecraft would not be able to get to the surface of the Sun it would definitely get close enough to answer three very important questions. Why is the Sun’s surface, which is called photosphere, not as hot as its atmosphere?. What accelerates the speed of the solar wind?.Why does the Sun occasionally emit high-energy particles that pose a danger to unprotected astronauts and spacecraft?.Christian explained the queries by saying that according to the data collected by NASA, the surface temperature of the Sun is only 5500 degrees Celsius but the temperature of its atmosphere is about two million degrees Celsius and generally the farther away you go from the heat source, the colder it gets but with the Sun, it’s the opposite.Further, he added that the Sun blows a stream of charged particles in all directions at a million miles an hour however, it is not clear from where it gets that much speed.