New Delhi: NASA on Sunday launched its car-sized probe from Cape Canaveral Air Force Station in its first mission to "touch the Sun". It was scheduled to be launched on Saturday but the launch was delayed due to a "violation of a launch limit", as cited by NASA.
"The launch of a United Launch Alliance Delta IV Heavy rocket carrying the Parker Solar Probe spacecraft was scrubbed today due to a violation of a launch limit, resulting in a hold. There was not enough time remaining in the window to recycle," NASA said in a blog post.
"The forecast shows a 60 per cent chance of favourable weather conditions for launch," the post added. The Parker Solar Probe was sent on a a United Launch Alliance Delta IV Heavy, according to NASA.
The magnetized material sent outward by the Sun's atmosphere envelops our solar system far beyond the orbit of Pluto.
"The Thermal Protection System (the heat shield) is one of the spacecraft's mission-enabling technologies," said Andy Driesman, Parker Solar Probe project manager at the Johns Hopkins Applied Physics Lab. "It allows the spacecraft to operate at about room temperature."
"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 Guo Yanping from the Johns Hopkins Applied Physics Laboratory, who designed the mission trajectory.
The United Launch Alliance Delta IV Heavy is one of the most powerful rockets in the world.
"During summer, Earth and the other planets in our solar system are in the most favourable alignment to allow us to get close to the Sun," said Guo.
The Parker Solar Probe weighs just 635 kgs, Andy Driesman, project manager for the mission at the Johns Hopkins University Applied Physics Laboratory in the US, said in an earlier statement issued by NASA.
"And it needs to be, because it takes an immense amount of energy to get to our final orbit around the Sun," Driesman added.
The probe will zoom through space in a highly elliptical orbit and will reach speeds of up to 7,00,000 kms per hour, becoming the fastest spacecraft in history.
The mission lifetime will be under seven years during which the spacecraft will complete 24 orbits of the Sun and will reach within 3.8 million miles of the Sun's surface at the closest approach.
"Recent advances in materials science gave us the material to fashion a heat shield in front of the spacecraft not only to withstand the extreme heat of the Sun, but to remain cool on the backside," said Adam Szabo, the mission scientist for the Parker Solar Probe at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
The heat shield has been made of 4.5-inch thick carbon composite foam material between two carbon fibre face sheets.
When the probe will make its closest approach to the Sun, the temperatures on the heat shield will reach nearly 1,371 degrees Celsius, but the spacecraft and its instruments will be kept at a temperature of about 29.4 degrees Celsius.