“This probe will journey to a region humanity has never explored before,” said Thomas Zurbuchen, the associate administrator for the Science Mission Directorate at NASA Headquarters in Washington.

“This mission will answer questions scientists have sought to uncover for more than six decades.” Understanding the Sun has always been a top priority for space scientists. Studying how the Sun affects space and the space environment of planets is the field known as heliophysics.

The field is not only vital to understanding Earth’s most important and life-sustaining star, it supports exploration in the solar system and beyond.  The spacecraft, about the size of a small car, will travel directly into the Sun's atmosphere about 4 million miles from the star's surface.

The primary science goals for the mission are to trace how energy and heat move through the solar corona and to explore what accelerates the solar wind as well as solar energetic particles.

The mission will revolutionize our understanding of the Sun, where changing conditions can spread out into the solar system, affecting Earth and other worlds.

To perform these unprecedented investigations, the spacecraft and instruments will be protected from the Sun’s heat by a 4.5-inch-thick carbon-composite shield, which will need to withstand temperatures outside the spacecraft that reach nearly 2,500 F.

This state-of-the-art heat shield will keep the four instrument suites designed to study magnetic fields, plasma and energetic particles, and image the solar wind at room temperature. The spacecraft speed is so fast, at its closest approach it will be going at approximately 430,000 mph. That's fast enough to get from Washington, D.C., to Tokyo in under a minute.

“Parker Solar Probe is, quite literally, the fastest, hottest — and, to me, coolest — mission under the Sun,” said project scientist Nicola Fox, of the Johns Hopkins Applied Physics Laboratory.

“This incredible spacecraft is going to reveal so much about our star and how it works that we’ve not been able to understand.”