Scheduled for an August 4 launch, NASA’s Parker Solar Probe was fitted with a state-of-the-art heat shield less than two weeks ago, according to a July 5 statement published on the space agency’s website.
In a way, it was a reinstallation of the shield, as it was temporarily attached to the probe for testing purposes at the Johns Hopkins Applied Physics Lab in Laurel, Maryland, in 2017
Called the Thermal Protection Unit (TPU), the heat shield measures eight feet in diameter and is designed to protect everything that lies within its umbra – the shadow it casts on the probe.
As Parker zips around the sun within 4 million miles of its fiery surface – the space equivalent of touching distance, you can say – the temperatures the TPU will have to withstand to protect the spacecraft will reach 1,370 degrees Celsius (2,500 degrees Fahrenheit).
NASA describes the 160-pound TPU as a heat shield “made up of two panels of superheated carbon-carbon composite sandwiching a lightweight 4.5-inch-thick carbon foam core.”
Also, the side that will be exposed to all that heat has been “sprayed with a specially formulated white coating to reflect as much of the Sun’s energy away from the spacecraft as possible.”
Not bigger than a small car, Parker will be launched in space atop a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, after which it will begin its three-month-long journey to the sun’s corona.
Traveling at speeds of up to 435,000 miles per hour (700,000 km/h) through the corona, the instrument-loaded probe will orbit the sun 24 times, collecting important scientific data and beaming it back to earth, as early as December.
Data such as 3-D images, electric and magnetic field recordings, and high-energy particle catalogs will go a long way in helping scientists better understand the workings of the sun and its corona.
It will enable scientists to safeguard spacecraft, astronauts, and sensitive ground equipment through improved space weather forecast, and more, in times to come.
All that data “is going to answer a lot of questions that we couldn’t answer in any other way,” says Craig DeForest, a heliophysicist at the Southwest Research Institute in Boulder, Colorado.
“There’s been a tremendous amount of anticipation,” DeForest, who is not involved in the mission in any capacity, added.
“A mission 60 years in the making, Parker Solar Probe will make a historic journey to the Sun’s corona, a region of the solar atmosphere,” read the NASA statement.
“With the help of its revolutionary heat shield, now permanently attached to the spacecraft in preparation for its August 2018 launch, the spacecraft’s orbit will carry it to within 4 million miles of the Sun’s fiercely hot surface, where it will collect unprecedented data about the inner workings of the corona.”
Part of NASA’s LWS (Living with a Star) program, the Parker Solar Probe will, basically, explore those facets and characteristics of the sun that are directly related to our planet, influencing life and society.
While the LWS is managed by Goddard for the Heliophysics Division of NASA’s Science Mission Directorate in Washington, D.C., the Parker Solar Probe program is overseen by the Johns Hopkins Applied Physics Laboratory, on behalf of NASA.
After Parker has completed its 24-orbit mission around the sun, it is expected to have some leftover fuel to continue along for some time, until it is unable to fire its thrusters that keep the shielded side towards the sun, says project scientist Nicola Fox, who’s also a heliophysicist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.
With its unprotected part exposed to the merciless heat and radiation, Parker will start disintegrating into large pieces, which will get increasingly smaller until there’s nothing left but dust across the sun’s corona.
NASA has invited members of the media at the Astrotech Space Operations payload processing facility in Titusville, Florida, on July 13, to not only view and photograph the amazing Parker Solar Probe but also meet with project and program officials for any queries they might have, ahead of mission launch next month.
Not to be left out of the race, European Space Agency (ESA) will launch its own sunward-bound Solar Orbiter sometime in 2020, which will beam direct images of the sun’s poles.
Combining the data from the two spacecraft, providing different perspectives of the sun, will enable scientists to understand “how the solar wind varies at different latitudes,” says NASA.