Sun seeker on its way
Spacecraft aims to get closest look at dwarf star
ANasa spacecraft rocketed toward the sun last night on an unprecedented quest to get closer to our star than anything sent before.
The Parker Solar Probe will fly straight through the wispy edges of the corona, or outer solar atmosphere, that was visible during last August’s total solar eclipse. It eventually will get within 6 million km of the sun’s surface, staying comfortably cool despite the extreme heat and radiation, and allowing scientists to vicariously explore the sun in a way never before possible.
“Fly baby girl, fly!!” project scientist Nicola Fox of Johns Hopkins University tweeted just before liftoff. She urged it to “go touch the sun!”
Protected by a revolutionary new carbon heat shield and other high-tech wonders, the spacecraft will zip past Venus in October. That will set up the first solar encounter in November. Altogether, the Parker probe will make 24 close approaches to the sun on the seven-year, $1.5 billion undertaking.
For the second straight day, thousands of spectators jammed the launch site in the middle of the night as well as surrounding towns, including 91-year-old astrophysicist Eugene Parker for whom the spacecraft is named. He proposed the existence of solar wind — a steady, supersonic stream of particles blasting off the sun — 60 years ago.
It was the first time Nasa named a spacecraft after someone still alive, and Parker wasn’t about to let it take off without him. Saturday’s launch attempt was
Fly baby girl, fly!! Go touch the sun! Nicola Fox
foiled by last-minute technical trouble.
The Delta IV Heavy rocket thundered into the pre-dawn darkness, thrilling onlookers for miles. Nasa needed the mighty 23-storey rocket, plus a third stage, to get the Parker probe — the size of a small car and under a ton — racing toward the sun.
From Earth, it is 150m km and the Parker probe will be within 4 per cent of that distance. That will be seven times closer than previous spacecraft.
On its very first brush with the sun, it will come within 25m km, easily beating the current record set by Nasa’s Helios 2 spacecraft in 1976. By the time Parker gets to its 22nd orbit of the sun, it will be deeper into the corona and travelling at a record-breaking 690,000km/h.
Even Fox has trouble comprehending the mission’s derring-do.
“To me, it’s still mindblowing,” she said. “Even I still go, ‘really? We’re doing that?’”
Nasa’s science mission chief Thomas Zurbuchen considers the sun the most important star in our universe. By better understanding the sun’s life-giving and sometimes violent nature, Earthlings can better protect satellites and astronauts in orbit, and power grids on the ground, he noted. In today’s tech-dependent society, everyone stands to benefit.
With this mission, scientists hope to unlock the many mysteries of the sun, a commonplace yellow dwarf star around 4.5 billion years old. Among the puzzlers: Why is the corona hundreds of times hotter than the surface of the sun and why is the sun’s atmosphere continually expanding and accelerating, as the University of Chicago’s Parker accurately predicted in 1958?
“The only way we can do that is to finally go up and touch the sun,” Fox said.