The findings will also make critical contributions to our ability to forecast changes in Earth's space environment that affect life and technology on Earth.
A Saturday morning launch attempt was foiled by last-minute technical trouble.
It will face brutal heat and radiation conditions to provide researchers with the closest observations of a star.
"Go, baby, go!" project scientist Nicola Fox of Johns Hopkins University shouted at liftoff. This first flyby will place Parker Solar Probe in position in early November to fly as close as 15 million miles from the Sun - within the blazing solar atmosphere, known as the corona - closer than anything made by humanity has ever gone before. By better understanding the sun's life-giving and sometimes violent nature, Earthlings can better protect satellites and astronauts in orbit, and power grids on the ground, he noted.
But it's only been in the past few years that scientists and engineers could put together a space mission capable of going close enough to get the data to back up the theory.More news: Blizzard confirms it is working on multiple new Diablo projects
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Nasa chief of the science mission directorate, Thomas Zurbuchen, said Mr Parker was an "incredible hero of our scientific community" and called the probe one of Nasa's most "strategically important" missions.
Even in a region where temperatures can reach more than a million degrees Fahrenheit, the sunlight is expected to heat the shield to just around 2,500 degrees Fahrenheit (1,371 degrees Celsius). With a communication lag time of 16 minutes, the spacecraft must fend for itself at the sun.
Its maximum velocity around the sun will reach 430,000 miles per hour, making it the fastest human-made object to orbit a celestial body.
Parker Solar Probe carries four instrument suites created to study magnetic fields, plasma and energetic particles, and capture images of the solar wind.
The Parker Solar Probe carries a lineup of instruments to study the Sun both remotely and in situ, or directly.
Main objectives of Parker Solar Probe?
Moreover, the spacecraft holds a microchip carrying the names of more than 1.1 million participants who signed up to send their name to the Sun. "The way I like to think about it: In 10 to 20 years, a carbon disk will be floating around the sun in orbit, and it will be around until the end of the solar system". "Parker Solar Probe would be just 4cm away from the Sun", explained Dr Fox. These will help determine the structure and dynamics of the magnetic fields at the sources of solar wind, trace the flow of energy that heats the corona and accelerates the solar wind, and determine what mechanisms accelerate and transport energetic particles.
Now the University of Chicago professor has had the last laugh with the probe named after him - the first living person to be so honoured.