Solar Orbiter blasts off to capture first look at sun's poles

[Spartan]

Europe and NASA's Solar Orbiter rocketed into space Sunday night on an unprecedented mission to capture the first pictures of the sun's elusive poles.

The $1.5 billion spacecraft will join NASA's Parker Solar Probe, launched 1 1/2 years ago, in coming perilously close to the sun in order to unveil its secrets.

While Solar Orbiter won't venture close enough to penetrate the sun's corona, or crown-like outer atmosphere, like Parker, it will maneuver into a unique out-of-plane orbit that will take it over both poles, never photographed before. Together with powerful ground observatories, the sun-staring space duo will be like an orchestra, according to Gunther Hasinger, the European Space Agency's science director.

"Every instrument plays a different tune, but together they play the symphony of the sun," Hasinger said.

Solar Orbiter was made in Europe, along with nine science instruments. NASA provided the 10th instrument and arranged the late-night launch from Cape Canaveral.

Nearly 1,000 scientists and engineers from across Europe gathered with their U.S. colleagues under a full moon as United Launch Alliance's Atlas V rocket blasted off, illuminating the sky for miles around. Crowds also jammed nearby roads and beaches.

The rocket was visible for four full minutes after liftoff, a brilliant star piercing the night sky. Europe's project scientist Daniel Mueller was thrilled, calling it "picture perfect." His NASA counterpart, scientist Holly Gilbert, exclaimed, "One word: Wow."

Solar Orbiter — a boxy 4,000-pound spacecraft with spindly instrument booms and antennas — will swing past Venus in December and again next year, and then past Earth, using the planets' gravity to alter its path. Full science operations will begin in late 2021, with the first close solar encounter in 2022 and more every six months.

At its closest approach, Solar Orbiter will come within 26 million miles of the sun, well within the orbit of Mercury.

Parker Solar Probe, by contrast, has already passed within 11.6 million miles of the sun, an all-time record, and is shooting for a slim gap of 4 million miles by 2025. But it's flying nowhere near the poles. That's where Solar Orbiter will shine.

The sun's poles are pockmarked with dark, constantly shifting coronal holes. They're hubs for the sun's magnetic field, flipping polarity every 11 years.

Solar Orbiter's head-on views should finally yield a full 3-D view of the sun, 93 million miles from our home planet.

[Spartan]