The car-sized spacecraft will be launched from Florida's Cape Canaveral on Saturday at around 3:50 am eastern standard time.
The spacecraft will fly through the sun's corona multiple times to answer several questions, like why it is millions of degrees hotter than the surface of the sun itself.
The last time a man-made object came close to the star's surface was in 1976 when Helios 2 achieved perihelion, point of the orbit at which it was closest to the sun, at 27 million miles.
In addition to bringing humanity closer to the Sun than ever before, the unmanned probe will also set a new speed record for a manmade object when it reaches 430,000 miles per hour in 2024.
The craft comes equipped with a thick shield made of carbon composite foam and carbon fiber.
The spacecraft eventually will run out of fuel and, no longer be able to keep its heat shield pointed toward the Sun, will burn and break apart - except perhaps for the rugged heat shield.
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"The sun is full of mysteries", said Nicky Fox, project scientist at the Johns Hopkins University Applied Physics Lab.
Scientists have wanted to build a spacecraft like this for more than 60 years, but only in recent years did the heat shield technology advance enough to be capable of protecting sensitive instruments, according to Fox. Parker is now 91 years old and at Cape Canaveral with his family to witness his first launch - a Delta IV Heavy rocket with the spacecraft bearing his name.
"It was just a matter of sitting out the deniers for four years until the Venus Mariner 2 spacecraft showed that, by golly, there was a solar wind", Parker said earlier this week.
On each close approach to the sun, the probe will sample the solar wind, study the sun's corona, and provide close-up observations from around the star.
"We will also be listening for plasma waves that we know flow around when particles move", Fox added.
The probe will travel at 430,000 miles an hour, faster than any spacecraft in history, and use Venus's gravity over the course of seven years to gradually bring its orbit closer to the sun.
A LEARNING OPPORTUNITY. Ultimately, the more we can learn about the Sun, the better.