NASA’s Sun probe sheds new light on our star — here are 5 new secrets it uncovered

Illustration of the Parker Solar Probe spacecraft approaching the SunJohns Hopkins University Applied Physics Laboratory
  • The National Aeronautics and Space Administration (NASA) published its first findings from the Parker Solar Probe.
  • On its mission to get closer than anyone in history, Parker has uncovered five new secrets about the Sun that were previously unknown — including a dust-free zone.
  • These new facts can help scientists devise better defenses against radiation causing solar particles that pose a threat to spacecraft and astronauts in outer space.
The National Aeronautics and Space Administration’s (NASA) Parker Solar Probe is on a mission to get closer to the Sun than any other human object. Inching closer as it orbits the solar system’s local star, Parker uncovered that Earth’s understanding of the Sun might be deceptively simple.

"This first data from Parker reveals our star, the Sun, in new and surprising ways," said Thomas Zurbuchen, associate administrator for science at NASA headquarters.

The findings, published across four papers in Nature, analyse solar wind — the continuous outflow of magnetic fields from the Sun — and the solar particles within it. It’s the key to understanding solar weather, according to NASA’s Goddard Space Flight Center.

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On Earth, humans are protected from solar particles as the planet’s atmosphere and magnetosphere ward them off. In outer space, they can cause radiation poisoning — which poses a threat to both spacecraft and astronauts.

With new information, scientists can devise better defenses to shield them.

Here are five new things we now know about the Sun that can help:
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​One of the only places in the solar system without dust

​One of the only places in the solar system without dust

On clear nights, observers from Earth can see a hint of this dust — known as Zodiacal dust or "false dawn," — as a concentrated illuminated cloud appearing over the horizon, scattering the Sun's light back to us in the dark (Source: NASA)

Cosmic dust is everywhere — or so we thought. So far, scientists have seen it drizzled all over space. Even on Earth, it can be seen filling the horizon reflecting sunlight.

Now, we know that 5.6 million kilometers from the Sun’s surface lays a ‘dust-free’ zone. NASA finds that as dust gets closer to the star, the heat vaporises it out of existence.

​The Sun’s has way more outbursts than expected, threatening astronauts in space

​The Sun’s has way more outbursts than expected, threatening astronauts in space

Parker's ISOIS energetic particle instruments have measured several never-before-seen events so small that all trace of them is lost before they reach Earth (Source: NASA)

Scientists have observed the Sun’s burst of solar energetic particles in the past, but these outbursts are generally large and irregular. These fast-moving particles are a source of radiation, posing a danger to astronauts and spacecraft as they travel through space or explore the Moon — which lacks any atmospheric protection.

And, these might be more common than previously thought. Parker finds that smaller outbursts of solar energetic particles are happening on a regular basis. Because they’re so small, the particles are undetectable from Earth as they spread out into space.

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​Magnetic fields that do a complete 180

​Magnetic fields that do a complete 180

Flips in the Sun's magnetic fields — dubbed "switchbacks" — appear to be a very common phenomenon as they flow over NASA's Parker Solar Probe during its first year in orbit (Source: NASA)

Until now, as observed from Earth, the Sun’s magnetic field look like they flow out evenly off its surface. That might no longer be the case.

Parker’s observations show that the magnetic field lines flip in a whip-like motion. Within a matter of seconds, they are able to turn a complete 180 degrees. These movements come in clusters along with fast-moving clumps of plasma in the solar wind.

​It’s not all smooth

​It’s not all smooth

NASA's Parker Solar Probe observed a slow solar wind flowing out from the small coronal hole — the long, thin black spot seen on the left side of the Sun in this image captured by NASA's Solar Dynamics Observatory (Source: NASA)

It’s been a conundrum to scientists where the solar wind flows in a smooth continuous slow or whether its generate in erratic spurts. And, the answer is neither.

Parker finds that solar winds have rough, irregular texture. The plasma within them doesn’t have a sense of direction either. Half the time it flies randomly out into space and the rest it falls back towards the Sun. In fact, these clumps of plasma might be the reason behind the ‘whip’ in the Sun’s magnetic field.

Even so, the new information shows scientists what solar wind looks like in its nascent stages for the very first time.

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The point where solar winds straighten out before reaching Earth

The point where solar winds straighten out before reaching Earth

Parker located a transition region in the solar wind's flow (Source: NASA)

The Sun’s corona — it’s faint, outer-most layer — rotates along with the surface below. But by the time solar winds reach Earth, they aren’t rotating but flowing in a straight pattern. And, Parker point the point where the switch happens.

This ‘transition point’ happens significantly farther out than scientists expected.