The probe will take mankind nearer to the
sun than ever before, withstanding temperatures that could melt steel...but not yet.
The launch of
NASA's
spacecraft to the sun has been delayed by 24 hours.
The probe was scheduled to launch at 8.53am UK time on the back of a United Launch Alliance Delta IV Heavy rocket, the second most powerful rocket in operation globally.
Just minutes beforehand, however, NASA announced the launch had been delayed due to "a condition" but a new launch time was later set for 9.28am UK time.
But technical problems defeated the launch a second time just one minute and 55 seconds before launch, with NASA tweeting: "This morning's launch of the
Parker Solar Probe was scrubbed.
"Launch teams will attempt to launch on Sunday morning."
Thousands of people had gathered at Florida's Cape Canaveral to watch the launch, which was due to take place at 4.38am local time.
Among them was Eugene Parker, the University of Chicago astrophysicist for whom the spacecraft is named.
Mr Parker predicted the existence of solar wind 60 years ago and now, at the age of 91, he is keen to see the probe launched.
As the Parker Solar Probe probe orbits the sun, it will experience extreme radiation and temperatures as high as 1,377C (2,510F) - close to the melting point of steel.
To handle the heat it has been covered with a special 4.5 inch (11.3 cm) thick carbon-composite shield capable of withstanding temperatures up to 1,650C (3,002F).
It will get more than seven times closer than the current record holder for a close solar pass, a record set by the Helios 2 spacecraft in 1976.
"The primary science goals for the mission are to trace how energy and heat move through the solar corona and to explore what accelerates the solar wind as well as solar energetic particles," explained NASA.
"Scientists have sought these answers for more than 60 years, but the investigation requires sending a probe right through the 2,500 degrees Fahrenheit heat of the corona.
"Today, this is finally possible with cutting-edge thermal engineering advances that can protect the mission on its dangerous journey.
"Parker Solar Probe will carry four instrument suites designed to study magnetic fields, plasma and energetic particles, and image the solar wind."
After it launches, the probe will travel at 430,000mph, the fastest speed ever achieved by a spacecraft.
NASA stated: "Parker Solar Probe will provide unprecedented information about our sun, where changing conditions can spread out into the solar system to affect Earth and other worlds."
The probe is going to fly directly into the sun's atmosphere and trace the movement of energy and heat with the particles that form solar winds.
It will take six years to reach its closest point to the sun, in 2024, by using Venus' gravity to bring itself nearer to the star.
The probe will help scientists understand more about the nature of the sun by taking measurements of solar winds, a flow of ionised gases.
If scientists understand more about solar activity, they could use it to predict large solar eruptions that pose a threat to satellites orbiting the Earth.
Scientists also hope the probe can help them to answer why the corona, the outermost layer of the sun's atmosphere, is 300 times hotter than its surface.
This is a phenomenon that has baffled NASA scientists because the sun's atmosphere "gets much, much hotter the farther it stretches from the sun's blazing surface".
The probe will be controlled from the Mission Operations Centre based at the Johns Hopkins University Applied Physics Laboratory (JHU APL), which is where NASA handles its unmanned missions.
Manned missions, such as the Apollo moon landings, were run from the Christopher C Kraft Mission Control Centre in Houston, from where it earned its famous radio call sign.