At this point, the probe will be moving at roughly 430,000 miles per hour, setting the record for the fastest-moving object made by humanity.
These explosions create space weather events that can pummel Earth with high energy particles, endangering astronauts, interfering with Global Positioning System and communications satellites and, at their worst, disrupting our power grid.
The mission had been expected to launch on Saturday, but was delayed at the last minute due to a technical problem. A special component of SWEAP is a small instrument that will look around the protective heat shield of the spacecraft directly at the sun, the only instrument on the spacecraft to do so.
"The only way we can do that is to finally go up and touch the sun", the $1.5 billion mission's project scientist, Nicola Fox of Johns Hopkins University's Applied Physics Laboratory, told reporters in advance of today's launch.
"The mission will unlock mysteries of the corona, including why it's so much hotter than the surface of the sun which is about 10,000 Farenheit", Brown said.
Using Venus' gravity to pick up speed, the NASA probe will complete seven flybys in seven years to gradually bring its orbit closer to the Sun. The cup will glow red when the probe makes its closest approach to the sun, sampling the solar wind and effectively touching the sun.
But then, the launch of NASA's Mariner 2 spacecraft in 1962 - becoming the first robotic spacecraft to make a successful planetary encounter - proved them wrong.
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.
At closest approach to the sun, the front of PSP's solar shield faces temperatures approaching 2,500 degrees F. The spacecraft's payload will be near room temperature.
Such automation is needed because sunlight takes eight minutes to reach Earth 93 million miles away. At these distances the sun will be over 500 times brighter than it appears to Earth, and particle radiation from solar activity will be harsh.
The spacecraft, which will plunge into the sun's atmosphere, known as the corona, is protected by an ultra-powerful heat shield.
The Parker solar probe is named after Eugene Parker, in recognition of his contribution to the study of the sun and of solar wind in particular.
Several other designs on the spacecraft keep Parker Solar Probe sheltered from the heat. FIELDS will measure electric and magnetic waves around the probe, WISPR will take images, SWEAP will count charged particles and measure their properties, and ISOIS will measure the particles across a wide spectrum.
Parker Solar Probe will revolutionize our understanding of the Sun's corona.
The University of Chicago professor said he had been biting his nails in anticipation.
"I realise that might not sound that close, but imagine the Sun and the Earth were a metre apart". He's now 91 and eager to see the solar probe soar.