NASA is preparing to launch a mission that will go where no probe has gone before: the sun. Not just in orbit of the sun, either. The Parker Solar Probe will come as close as possible to touching the sun without being swallowed up by waves of superheated plasma. Parker will blast through the sun’s corona, sending back data that could revolutionize our understanding of stars.
The launch is currently on track for as soon as August 11th with a Delta IV Heavy rocket, which is one of the most powerful launch vehicles in the world. The Heavy variant of this rocket has a third stage added for additional thrust, and the Parker Solar Probe will take full advantage. The probe itself is fairly small, just 1,400 pounds (635 kilograms) or about the same as a compact car. When it lifts off, Parker will become the fastest human spacecraft ever, a record currently held by the New Horizons Pluto probe launched in 2006. NASA estimates that Parker will hit 430,000 miles per hour (about 692,000 kilometers per hour).
After launch, Parker will need to bleed off some of that speed to make a safe approach of the sun and enter orbit. It will use a gravity slingshot around Venus to get that done. The Venus encounter will also swing the craft around to the best angle to meet up with the sun. Parker will actually rendezvous with Venus seven times during the mission, each time bringing it closer to the surface of the sun on its next orbit. NASA plans for a seven-year Parker mission consisting of 24 orbits of the sun.
At its closest approach, Parker will get within 3.8 million miles of the sun’s surface. That’s closer than any other spacecraft and within the corona. NASA has wanted to launch a mission like this for decades, but the technology to protect a spacecraft simply didn’t exist. The corona is home to solar material heated to millions of degrees and massive events like solar flares and coronal mass ejections.
Being inside the corona will allow scientists to collect more data than they ever could using remote coronal observations from more distant spacecraft. To keep Parker running for the full seven-year mission, NASA developed an advanced heat shield consisting of 4.5-inch carbon composite foam between two carbon fiber sheets. While the sun-facing side of the shield will hit 2,500 degrees Fahrenheit (1,371 degrees Celsius), the probe side will be a pleasant 85 degrees Fahrenheit (29.4 degrees Celsius).
NASA expects Parker to make its first close approach of the sun about three months after launch. Data will come back to Earth in December of this year.
Parker Solar Probe Beams Back Data From the Sun’s Corona
Parker has already completed its first flyby of the sun's corona, and NASA says the probe's early performance is everything the team could have hoped for.