The Sun is sending out sudden, violent bursts of solar wind so powerful that the magnetic field flowing out from the Sun flips itself in the opposite direction.
That’s the totally unexpected news sent back to Earth from NASA’s Parker Solar Probe, the car-sized spacecraft launched in 2018. Its mission is to journey closer to the Sun than any other human-made object.
Parker has sent back masses of information from its close encounter with the Sun, which scientists have published in recent days.
The information is helping them understand how the Sun makes the weather in space and the impacts of the violent solar wind that can hamper* satellites and electronics on Earth.
“We were certainly hoping we’d see new phenomena* and new processes when we got close to the Sun – and we certainly did,” said Nicola Fox, director of the US space agency’s heliophysics* division.
“Some of the information that we found pretty much confirmed what we expected, but some of it is totally unexpected.”
Earth is roughly 150 million km from the Sun. The probe ventured as close as 24 million km to the Sun to gather the data used in the studies published in the journal Nature. On its last approach, the probe will get as close as 6 million km from the sun’s surface, seven times closer than any previous spacecraft.
The probe has endured extreme heat while flying through the outermost part of the Sun’s atmosphere, called the solar corona, that gives rise to solar wind – the hot, energised, charged particles that stream outward from the Sun and fill the solar system.
Despite the extreme heat, the instruments on-board have to stay at room temperature. The spacecraft is protected by a hi-tech solar shield that swivels to stay between the body of the spacecraft and the Sun and includes, among other things, carbon fibre panels, which here on Earth we use to make expensive bike frames and racing yachts.
One of the probe’s “really big surprises,” according to one of the researchers, was the detection of sudden, abrupt spikes in the speed of the solar wind.
The bursts were so violent that the magnetic field flips itself around, a phenomenon called “switchbacks.”
Dr Fox compared this unexpected switchback phenomenon to the cracking of a whip.
“We’re finding these discrete*, powerful waves that wash over the spacecraft, kind of like rogue* waves in an ocean,” said Justin Kasper, a principal investigator whose team at the University of Michigan, US, built a solar wind-sensing instrument on the Parker probe. “They carry a tremendous amount of energy.”
“This will dramatically change our theories for how the corona and solar wind are being heated,” Kasper said.
Researchers said they also finally have evidence of a dust-free zone encircling* the Sun. Farther out, there’s so much dust from vaporising* comets and asteroids that one of 80 small viewfinders on one instrument was pierced by a dust grain earlier this year.
Parker will sweep past Venus on December 26 to get a speed boost from the planet’s gravity.
It will make its fourth close solar encounter in January.
- hamper: hinder; hold back; make things difficult
- phenomena: plural of phenomenon; things we notice
- heliophysics: the science of the Sun
- discrete: separate
- rogue: something separate from the rest and destructive
- encircling: making a circle around
- vaporising: turning into vapour, or a gas
- How big is the Parker Solar Probe and when did it launch?
- How close did the probe get to the Sun?
- Explain what a switchback is?
- What did the team at the University of Michigan build?
- What will the probe do on December 26?
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1. Use your words
Below is a list of words taken from the news article. Correctly use all of these words by including them in sentences that give information about the Parker Solar Probe. Challenge yourself by trying to use up all of the words in the least number of sentences possible! Who in your class can use up all of the words using the smallest number of sentences?
- must make sense
- must be factual
- may not use the connective (conjunction) “and” but may use other connectives
Words to use: solar; magnetic; switchback; corona; wind; particles; energy; heat; atmosphere; carbon
Time: allow 30 minutes to complete this activity
Curriculum Links: English; Science
Get a better picture in your mind (visualise) how close the probe will go to the Sun by doing the following:
Find the paragraph that details the distances between Earth and the Sun, and how close the Parker Solar Probe has been/will go to the Sun.
Find objects in your classroom (e.g. balls, pencil sharpeners, etc.) to represent the Earth, Sun and the probe.
Use the objects to model the distances described on a much smaller scale. (Suggested scale: 1 million km = 1cm)
Time: allow 20 minutes to complete this activity
Curriculum Links: English; Science; Mathematics
With a partner see if you can identify all the doing words/verbs in this text. Highlight them in yellow and then make a list of them all down your page. Now see if you and your partner can come up with a synonym for the chosen verb. Make sure it still makes sense in the context it was taken from.
Try to replace some of the original verbs with your synonyms and discuss if any are better and why.
HAVE YOUR SAY: Where would you send a spacecraft to if you were in charge of NASA?
No one-word answers. Use full sentences to explain your thinking. No comments will be published until approved by editors.