Orbiter launched to explore the sun's poles

WASHINGTON－The US-European Solar Orbiter probe launched on Sunday night from Florida was on a voyage to deepen human understanding of the sun and how it shapes the space weather that impacts technology back on Earth.

The mission, a collaboration between the European Space Agency and NASA, successfully blasted off from the Kennedy Space Center in Cape Canaveral at 11:03pm local time and could last up to nine years or more.

At 12:24am on Monday, the European Space Operations Centre in Darmstadt, Germany, received a signal from the spacecraft indicating that its solar panels had successfully deployed.

Solar Orbiter is expected to provide unprecedented insights into the sun's atmosphere, its winds and its magnetic fields, including how it shapes the heliosphere, the vast swath of space that encompasses our solar system.

By journeying out of the ecliptic plane－the belt of space roughly aligned with the sun's equator, through which the planets orbit－it will acquire the first images of our star's uncharted polar regions.

Drawing on gravity assists from Earth and Venus, Solar Orbiter will slingshot itself into a bird's-eye view of the sun's poles, reaching its primary science orbit in two years' time.

"I think it was picture perfect, suddenly you really feel like you're connected to the entire solar system," said Daniel Muller, ESA project scientist, shortly after the launch.

"You're here on Earth and you're launching something that will go close to the sun."

"We have one common goal and that is to get the good science out of this mission. I think we're going to succeed," added Holly Gilbert, director of NASA's heliophysics science division.

Unlock clues

Ten state-of-the-art instruments on board will record myriad observations to help scientists unlock clues about what drives solar winds and flares.

These emit billions of highly charged particles that impact the Earth, producing the spectacular Northern Lights. But they can also disrupt radar systems, radio networks and even, though rarely, render satellites useless.

The largest solar storm on record hit North America in September 1859, knocking out much of the continent's telegraph network and bathing the skies in an aurora viewable as far away as the Caribbean.

"Imagine if just half of our satellites were destroyed," said Matthieu Berthomier, a researcher at the Paris-based Plasma Physics Laboratory. "It would be a disaster for mankind."

At its closest approach, Solar Orbiter will be nearer to the sun than Mercury, a mere 42 million kilometers away.

With a custom-designed titanium heat shield, it is built to withstand temperatures as high as 500 Celsius. Its heat-resistant structure is coated in a thin, black layer of calcium phosphate, a charcoal-like powder that is similar to pigments used in prehistoric cave paintings.

The shield will protect the instruments from extreme particle radiation emitted from solar explosions.

All but one of the spacecraft's telescopes will peep out through holes in the heat shield that open and close in a carefully orchestrated dance, while other instruments will work behind the shadow of the shield.

Just like Earth, the sun's poles are extreme regions quite different from the rest of the body. It is covered in coronal holes, cooler stretches where fast-gushing solar wind originates.

Scientists believe this region could be key to understanding what drives its magnetic activity.

Every 11 years, the sun's poles flip: north becoming south and vice versa. Just before this event, solar activity increases, sending powerful bursts of solar material into space.

Solar Orbiter will observe the surface as it explodes and record measurements as the material goes by the spacecraft.