The mission will be the first to fly directly through the Sun's corona - the hazardous region of intense heat and solar radiation in the Sun's atmosphere that is visible during an eclipse.
Dr Nicky Fox, the British-born project scientist affiliated to the Johns Hopkins Applied Physics Laboratory, explained to the BBC just how close the probe would get to to the sun.
In an unprecedented quest, the Parker Solar Probe will fly within 3.8 million miles of the sun's surface.
He proposed the existence of the solar wind 60 years ago.
The spacecraft will analyse so-called "space weather", which is large eruptions of radiation from the sun which batter Earth.
Scorching, yes? But if all works as planned, the inside of the spacecraft should stay at just 85 degrees Fahrenheit.
The goal for the Parker Solar Probe is to make 24 passes through the corona during its seven-year mission. The corona holds the answers to many of scientists' outstanding questions about the Sun's activity and processes.
The spacecraft is the only NASA probe in history to be named after a living person - in this case, 91-year-old solar physicist Eugene Parker, who first described the solar wind in 1958.
Parker, now 91, recalled that at first some people did not believe in his theory. The extreme pull of the sun's gravity will then accelerate the probe up to insane speeds of as much as 430,000 miles per hour (700,000 km/h) as it grazes the edge of the most powerful object in our corner of the galaxy. The reason for the delay was not immediately clear, but was called for after a gaseous helium alarm was sounded in the last moments before liftoff, officials said.
"We will also be listening for plasma waves that we know flow around when particles move", Fox added.
"We'll also be the fastest human-made object ever, travelling around the Sun at speeds of up to 690,000km/h (430,000mph) - NY to Tokyo in under a minute!" she told BBC News.