It’s NASA’s first big mission launch for some time.

It’s the Parker Solar Probe.

It’s a car-sized robot that’s just been catapulted into space.

Now, it’s a seven-year roundabout journey to graze the surface of the Sun.

It will use Venus as a slingshot, putting itself in a position to fly within 6 million km of the star’s surface. From there it will dip into the corona — the rarefied gas which envelopes the Sun, and which creates the spectacular glow around a total solar eclipse.

While it’s millions of kilometres from the Sun’s surface, the corona is actually 300 times hotter than what lies beneath. It’s also a violent place, buffeted by flares and firestorms beneath.

But the Parker Probe is expected to remain safe, shielded by an immense — and dense — plate of carbon composites placed between its delicate electrics and the raging inferno.

It’s going there to solve several mysteries.

How do the swirling magnetic and electric fields of the corona influence the solar wind?

What causes these charged particles to stream out into space at almost 3 million kilometres per hour?

Why is the corona so hot?

Its answers could shape the future of human spaceflight.

THE HEAT IS ON

It’s counterintuitive.

We’d expect the heat of the Sun to weaken as it gets further from its fusion core.

It doesn’t.

The Sun’s surface is calculated to be about 5500C.

The corona is 15,000,000C.

“It’s a bit like if you walked away from a campfire and suddenly got much hotter,” Parker Solar Probe’s project scientist Nicky Fox says.

How it gets that way is what the Parker Probe is intended to figure out.

It’s hoped the probe will get close enough to pick out traces of what’s heating the plasma before it reaches the corona.

And that’s no easy task.

It has taken decades to develop the technology necessary to make the Parker Probe possible.

It’s not just about looking directly into the Sun to see what’s going on. It’s also about keeping the probe alive.

The thermal protection system incorporates three essential elements.

The lightweight heat shield is essentially a reflective, carbon-composite umbrella. It will keep the probe itself in permanent shade, allowing the electronics to operate at room temperature — even as the shield itself bakes at 1400C.

The probe’s solar panels are outside this shield. They must extend outwards to catch the Sun’s electricity-generating rays. But, being so close, these panels will have to be, essentially, airconditioned. Otherwise, they’d melt. So a water coolant system has been devised to keep them operating at about 160C.

All this, and the probe’s sensitive systems, will be governed by an advanced fault management system. The probe will be regularly out-of-touch with the Earth. So it has to be able to protect itself if things go wrong. So on-board systems can self-correct the probe’s orientation to guarantee its safety.

It’s the culmination of six decades of work.

In 1958, physicist Eugene Parker published a radical scientific paper theorising the existence of the solar wind. The Parker Probe will now attempt to determine exactly how it is made.

CHASING THE WIND

The Sun’s surface goes through an 11-year cycle of relative calm, and chaos.

But it’s always hurling charged particles out into deep space, passing far beyond Pluto.

It’s not called space weather without reason.

Its moods can impact whole worlds.

“The Sun’s energy is always flowing past our world,” Fox says. “And even though the solar wind is invisible, we can see it encircling the poles as the aurora, which are beautiful — but reveal the enormous amount of energy and particles that cascade into our atmosphere. We don’t have a strong understanding of the mechanisms that drive that wind toward us, and that’s what we’re heading out to discover.”

Building the sensors capable of detecting — and surviving — such energy flows has been the major challenge for the mission.

And the objective is to find exactly where in the Sun’s atmosphere solar wind and energised particles are accelerated to their hypersonic speeds.

At the moment, we think it happens somewhere inside the corona.

“We’re interested in how powerful shockwaves driven outward from the Sun by massive eruptions of solar material, known as coronal mass ejections, can accelerate charged particles to extreme energies,” says Parker Solar Probe deputy project scientist Rob Decker. “As these shockwaves pass over, its instruments will measure the properties of the shockwaves and the charged particles in the early stages of the energisation process.”

The Parker probe will be flying directly through this maelstrom as it forms.

It’s these tendrils and coils of energy that can cannon through space, ripping into the Earth’s atmosphere and cause chaos with electricity grids, satellites and communications.

For those travelling in space, a direct hit could be lethal.

DEEP IMPACT

The radiation of deep space is one of the most significant hurdles we must overcome to make regular trips to the Moon and Mars — and anywhere else in our Solar System — viable.

Energised particles can rip through DNA at speed approaching half the speed of light, breaking apart the essential strands of information necessary to maintain life. They can also fry delicate circuit boards.

We’re usually safe, down here, on Earth. A magnetic shield swirls above us, generated by the molten metals at our planet’s core.

But its protection rapidly diminishes once in orbit.

Understanding how the solar wind is created and predicting its storms could be a vital part of the solution.

The Parker Probe’s job will be to take delicate measurements of the Sun’s moods. It’s hoped these will identify subtle signatures of impending storms and eruptions.

This way, astronauts can be warned of impending solar weather in much the same way we predict rain here on Earth.

All this, however, will take time.

The probe must make 22 orbits of the Sun as it is gingerly moved into position.

A little too close, and it melts.

A little too far, and it won’t be able to see what it needs to see.

It won’t arrive until 2024.

However, it won’t have time to sleep.

Its sensors will be active all the way, staring at the Sun.

@JamieSeidelNews