Here comes the sun, for real, up close

There’s something about the sun that makes us want to look its way.

Perhaps it’s the realization that this gigantic ball of blazing gases sustains life on our planet Earth, and that this world of ours would be nothing but a frigid, dead rock spinning through the dark enormities of space without the sun’s constant, enveloping rays.

Or maybe it’s because of the way the light from this nuclear-powered furnace coaxes us from slumber each morning and its warm caress makes our faces glow as we look skyward.

And we do look skyward, if carefully, knowing that staring at the midday sun would burn through our eyes and blind us forever.

So it was with our ancestors who raised temples to the sun, mourning its diminished powers each winter, joyfully welcoming its glorious return at every spring equinox.

And so it is with us today, we moderns, who have shown our atavistic, sun-worshipping inclinations by firing off a space probe that will travel closer to the centre of our solar system than any of its predecessors and unlock mysteries that will only make us marvel more at the sun.

That NASA spacecraft — the Parker Solar Probe — lifted off just over a week ago from Cape Canaveral, Florida.

It took a mighty, 23-storey Delta IV Heavy rocket to shoot this spacecraft — the size of a small car — heavenward. And it was aimed not directly at the heart of the sun but on a complex trajectory that will harness the gravitational forces of the planet Venus, forces that will catapult it closer and closer to the sun in 24 orbits over the next seven years.

We Earthlings gaze at the sun from a distance of 150 million kilometres. Parker will swing within just six million kilometres of the sun, 37 million kilometres closer than the current record set by NASA’s Helios 2 in 1976.

But the Parker probe is remarkable for more than the distance it will travel. During its closest solar approaches, the probe will set a speed record as it hurtles through the sun’s corona at 690,000 km/h.

Exploring the corona, a wispy, but harsh region where temperatures can reach millions of degrees Celsius, is one of Parker’s main goals.

It will be the first spaceship in history to enter this region. And it should be able to survive heat and radiation greater than any spaceship before it with the help of a lightweight heat shield a mere 11 centimetres thick.

Perhaps, after more than half a century of space exploration in which our first tentative steps in orbiting the Earth were followed by lunar landings, space stations and missions to Mars, we have become blasé about this kind of excursion.

We should resist the tendency. Parker is a marvellous marriage of human technology and imagination. In the words of the NASA space agency, this probe “will revolutionize our understanding of the sun.”

And that’s not hyperbole. NASA explains the spacecraft will “provide new data on solar activity and make critical contributions to our ability to forecast major space-weather events that impact life upon Earth.” Parker might, for instance, tell scientists what drives the solar wind, the supersonic stream of charged particles continually blasting out of the sun.

Practical minds, therefore, can rest assured this $1.5-billion undertaking will deliver scientific data at a relatively bargain-basement price.

Others, more romantically inclined, will experience an enlightening frisson of wonder. Astronomers might describe our sun as a rather ordinary, yellow dwarf star. Parker will remind us that size in this universe is relative and its glories are never commonplace.