As soon as this fall, the Parker Solar Probe will fly straight through the wispy edges of the sun's corona, or outer atmosphere, that was visible during last August's total solar eclipse.
A Saturday launch attempt was delayed due to a technical glitch.
"The key lies in its custom heat shield and an autonomous system that helps protect the mission from the Sun's intense light emission, but does allow the coronal material to "touch" the spacecraft", NASA said in a statement.
Six weeks after launch, the probe will encounter Venus' gravity for the first time.
The car-sized probe will give scientists a better understanding of solar wind and geomagnetic storms that risk wreaking chaos on Earth by knocking out the power grid.
The sunlight is expected to heat the shield to just around 2,500 degrees Fahrenheit (1,371 degrees Celsius). While granting us life, the sun also has the power to disrupt spacecraft in orbit, as well as communications and electronics on Earth.
"The launch energy to reach the Sun is 55 times that required to get to Mars, and two times that needed to get to Pluto", said Yanping Guo from the Johns Hopkins Applied Physics Laboratory, who designed the mission trajectory. It also holds a memory card containing more than 1.1 million names submitted by the public to travel with the spacecraft to the Sun. "We've looked at it, we've studied it from missions that are close in - even as close as the planet Mercury - but we have to go there".
"There's nothing like a rocket launch live", said Parker, now 91, who watched the launch from NASA's Kennedy Space Center.More news: Iran’s Khamenei rules out war, talks with U.S.
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Finally, after two firings of the second-stage engine, the Parker Solar Probe and its Northrup Grumman solid-fuel upper stage were released from the Delta 4.
The mission called Parker Solar Probe (PSP), commenced after a 24-hour delay.
U.S. space agency Nasa has launched its mission to send a satellite closer to the Sun than any before.
"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.
He proposed the existence of the solar wind 60 years ago.
"We always say that luck has absolutely nothing to do with this business, but I will take all that I can get", ULA Chief Executive Officer Tory Bruno said in an interview Friday.
The Solar Probe Cup, dubbed "the bravest little instrument", is a sensor that will extend beyond the heat shield to "scoop up samples" of the Sun's atmosphere, according to Professor Justin Kasper of the University of MI.
"Until you actually go there and touch the Sun, you really can't answer these questions", project scientist Nicola Fox told CBS News.
"We've had to wait so long for our technology to catch up with our dreams", Fox said.