Skip to Content

The closest ever approach to the sun has shown us the origin of solar wind

December 4, 2019
Parker Solar Probe
Parker Solar Probe
Parker Solar ProbeNASA/Johns Hopkins APL

The first major results from NASA’s Parker Solar Probe are in, a little over a year after the spacecraft set the record for the closest approach to the sun by an artificial object. 

Parker’s big year: Launched in August 2018, the Parker Solar Probe was built to study the sun and make the sharpest observations of the corona (the wreath of ultra-hot plasma that surrounds it). In October 2018, the probe came within 26.55 million miles (42.3 million kilometers)of the sun, surpassing the record set by the Helios 2 spacecraft in 1976.

The mission’s first results: The findings from that 2018 approach, published Wednesday in four new papers in Naturesuggest that solar wind and the sun’s magnetic field both originate from cool holes in the corona, where temperatures are 1.1 million °C (2 million °F).

The solar wind is a stream of charged particles belched out by the corona. The studies reveal that reversals in the sun’s magnetic field lines are responsible for accelerating this wind away from the sun. As the wind’s particles stream out of the cooler coronal holes, they move along the magnetic field lines. These lines will sometimes do a 180-degree flip, only to flip back to their original orientation anywhere from a few seconds to several hours later. These flips release lots of energy that acts upon the solar wind, sending it out into the solar system. Scientists are not yet able to explain what’s causing these flips, although they may have something to do with plasma jets that sometimes explode off the surface of the sun.

Why it matters: Solar wind has the potential to severely damage Earth’s electrical grids or other telecommunications equipment. Although the Earth’s own magnetic fields provide an excellent barrier against most solar wind, huge events could very easily knock out much of our infrastructure. Scientists hope that by learning more about the origin and behavior of solar wind, we can develop early warning systems for solar storms and figure out better strategies to guard against them.

What’s next: The Parker Solar Probe is far from finished. By 2025, it should get to within 3.9 million miles of sun's surface, facing temperatures of up to 1 370 °C and traveling as fast 430,000 miles per hour. 

Update: We have corrected an error in the final section

Keep Reading

Most Popular

transplant surgery
transplant surgery

The gene-edited pig heart given to a dying patient was infected with a pig virus

The first transplant of a genetically-modified pig heart into a human may have ended prematurely because of a well-known—and avoidable—risk.

open sourcing language models concept
open sourcing language models concept

Meta has built a massive new language AI—and it’s giving it away for free

Facebook’s parent company is inviting researchers to pore over and pick apart the flaws in its version of GPT-3

Muhammad bin Salman funds anti-aging research
Muhammad bin Salman funds anti-aging research

Saudi Arabia plans to spend $1 billion a year discovering treatments to slow aging

The oil kingdom fears that its population is aging at an accelerated rate and hopes to test drugs to reverse the problem. First up might be the diabetes drug metformin.

images created by Google Imagen
images created by Google Imagen

The dark secret behind those cute AI-generated animal images

Google Brain has revealed its own image-making AI, called Imagen. But don't expect to see anything that isn't wholesome.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at with a list of newsletters you’d like to receive.