New types of polar lights are upending what we know about the aurora. Amateur scientists and interns made the latest discoveries.
Summary List PlacementThe colorful lights that dance across polar skies create beautiful displays, but they also reveal mysteries about how planets, space, and the sun interact. Though humans have been observing the aurora for centuries, scientists are still learning about how it works. Just this year, amateur aurora-hunters discovered a new type of aurora that could come from space particles heating Earth's upper atmosphere. A NASA intern also revealed a new type of twisting aurora, which led scientists to a mysterious crunch in Earth's magnetic field. The lights at Earth's poles continue to surprise researchers, and other planets' aurorae offer hints at how their atmospheres and magnetic fields behave, too. Here's what researchers have learned about the aurora over the last few years.SEE ALSO: Astronauts on the space station see vibrant desert patterns, roiling storms, and volcanic eruptions. These are the best photos ever taken from the ISS. SEE ALSO: The first-ever space helicopter is en route to Mars in the belly of NASA's rover. It's set to record the first Martian drone footage. In January, amateur aurora chasers revealed a new type of aurora that stretches across the sky like fingers. They called it "the dunes."
Unlike regular aurorae, which spread down vertically from main ribbons of light, the dunes' patterns stretch horizontally. Scientists think the dunes could be a visible manifestation of atmospheric waves: undulations of air responding to regions of different temperatures or densities in the atmosphere.
"For the first time, we can actually observe atmospheric waves through the aurora – this is something that hasn't been done before," Minna Palmroth, a physicist and lead author of a study on auroral dunes, said in a press release. Based on video that the amateurs recorded, Palmroth thinks the dunes happen when electrical currents from space heat Earth's upper atmosphere. Youtube Embed: //www.youtube.com/embed/OMgsOyIuebc Width: 560px Height: 315px That's because the dunes seemed to appear when charged particles from space transferred energy into the upper atmosphere. That heat could create a type of atmospheric wave that makes horizontal curls and folds in the air, which then spread across the sky. "Different auroral forms are like fingerprints," Palmroth said.
"If you see a certain auroral form, you know basically from that form what's happening further out in space." A few other discoveries in recent years have also upended how scientists understand the northern and southern lights.
Near the North Pole, the atmospheric phenomenon that produces those lights is called the aurora borealis. Near the South Pole, it's called the aurora australis. Members of a group called the Alberta Aurora Chasers made one such discovery in 2016, when they spotted a strange purple arc in the sky.
They dubbed the mysterious new streak of light "Steve," which later came to stand for the Strong Thermal Emission Velocity Enhancement (STEVE). To figure out what this new phenomenon was, aurora researcher Eric Donovan tracked a satellite as it flew through a STEVE.
"In 1997 we had just one all-sky imager in North America to observe the aurora borealis from the ground," Donovan said in a press release from the European Space Agency, which built the satellite he used. "Back then we would be lucky if we got one photograph a night of the aurora taken from the ground that coincides with an observation from a satellite." The processes that create an aurora on Earth start at the sun, thanks to a constant stream of electrically charged particles called solar wind.
Events on the sun send out floods of the ions and electrons that make up solar wind. These charged particles travel almost at the speed of light. When these particles reach Earth, our planet's magnetic field funnels some of them to the poles, where they interact with our atmosphere to make the aurora.
Solar particles interacting with oxygen produce green and red light, while nitrogen glows blue and purple. Steve does not appear to come from these charged particles, however, which means it's technically not an aurora.
Rather, Donovan's satellite data suggested that STEVE came from a high-altitude ribbon of very hot gases burning at almost 5,500 degrees Fahrenheit (3,000 degrees Celsius). "It turns out that STEVE is actually remarkably common, but we hadn't noticed it before," Donovan said. Most true aurorae come at times of heightened solar activity, when big events like explosions on the sun flood Earth with charged particles.
Big explosions and electric storms on the sun can also cut off electronic communications, confuse GPS, push satellites out of orbit, endanger astronauts, or even wipe out power grids. Two such solar storms cut off emergency radio communications for a total of 11 hours following Hurricane Irma in 2017. But last year, NASA intern Jennifer Briggs discovered an aurora that didn't coincide with any extra activity from the sun.
Briggs spotted the twisting aurora in the above footage from an island in Norway. Her team checked the records and found no unusual solar activity at that time. "This eastward and then westward and then spiraling motion is not something that we've ever seen, not something we currently understand," she said in a press conference in December. Scientists connected the twisting northern lights to a huge compression in Earth's magnetic field, making it the first aurora of its kind.
"You can imagine someone punching Earth's magnetic field," Briggs said. "There was a massive but localized compression." Scientists think the mysterious compression may have come from a storm at the edges of the magnetic field. They don't know exactly what that might look like or where it could have come from. Other planets have their own aurora, often through the same processes as Earth's.
Unlike Earth, planets Jupiter, Saturn, Uranus, and Neptune have atmospheres mostly composed of hydrogen. So their aurorae are visible in ultraviolet light. Some of Jupiter's aurora comes from its moon, Io, which has large volcanoes that spew sulfur dioxide into space.
Jupiter's magnetic field also rips material off of Io regularly and funnels it towards the planet's poles, where the particles make the aurora. The charged particles that make Jupiters' aurora interact with its atmosphere to produce powerful X-rays. In 2017, researchers revealed a mystery in Jupiter's' aurorae: Its northern and southern lights aren't fluctuating together.
On Earth, the aurora borealis and aurora australis generally brighten and dim together, since Earth's magnetic field is distributing solar particles to both of them. But observations of Jupiter during solar storms show the aurorae on its northern and southern poles acting independently of each other. Nobody knows why.
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A record-breaking NASA probe circling the sun has found never-before-seen spikes of solar wind and a flipping magnetic field
NASA has released its first results from the Parker Solar Probe's close approaches to the sun....NASA has released its first results from the Parker Solar Probe's close approaches to the sun. For the first time, the probe found evidence of a zone with no cosmic dust, as well as a source of the solar wind of charged particles that streams from the sun. It also discovered previously unseen bursts of rapid solar wind that bend the sun's magnetic field backwards. The spacecraft will zip around the sun 21 more times in the next six years. Its findings could help scientists devise new protections for astronauts and Earth's electric grid. Visit Business Insider's homepage for more stories. NASA's record-breaking solar probe has discovered new, mysterious phenomena at the edge of the sun. Since it launched in August 2018, the Parker Solar Probe has rocketed around the sun three times, getting closer than any spacecraft before it and traveling faster than any other human-made object in history. On Wednesday, NASA scientists announced the probe's biggest discoveries so far, in four papers published in the journal Nature. The research revealed never-before-seen activity in the plasma and energy at the edges of the sun's atmosphere, including reversals of the sun's magnetic field and "bursts" in its stream of electrically charged particles, called solar wind. This wind surges into space and washes over Earth, so studying its source could help scientists figure out how to protect astronauts and Earth's electric grid from unpredictable, violent solar explosions. By sending the Parker probe to the sun, NASA is studying this dangerous wind in more detail than scientists could from Earth. "Imagine that we live halfway down a waterfall, and the water is always flowing past us. It's very turbulent, chaotic, unstructured, and we want to know what is the source of the waterfall up at the top," Stuart Bale, a physicist who leads the team that investigates the probe's solar wind data, said in a press call. "It's very hard to tell from halfway down." 'Bursty' solar wind bends the sun's magnetic field NASA scientists are seeking answers two major questions about the sun: What causes solar wind to accelerate as it shoots out into space? And why is the sun's outer layer, called the corona, up to 500 times hotter than its inner layers? The new data offers some initial clues. For the first time, Parker identified a clear source of a stream of slow, steady wind flowing out from the sun. It came from a hole in the corona — a spot where the gas is cooler and less dense. Scientists had previously known that wind coming from the sun's poles moves faster, but this was the first time they detected an origin point for the slow wind coming from its equator. The Parker probe also detected rogue waves of magnetic energy rushing through the solar wind. As those magnetic waves washed over the spacecraft, the Parker probe detected huge spikes in the speed of the solar wind — sometimes it jumped over 300,000 mph in just seconds. Then just as quickly, the rapid winds were gone. "We see that the solar wind is very bursty," Bale said. "It's bubbly, it's unstable. And this is not how it is near Earth." The bursts could explain why the corona is so hot. "We think it tells us, possibly, a path towards understanding how energy is getting from the sun into the atmosphere and heating it," Justin Kasper, another physicist who studied Parker's observations of solar wind, said in the call. Scientists had never observed these bursts and bubbles before, but they seem to be common. The Parker spacecraft observed about 1,000 of them in just 11 days. The rogue spikes of energy also delivered an additional surprise: The bursts are so strong that they flip the sun's magnetic field. The scientists call these events "switchbacks" because in the affected area, the sun's magnetic field whips backwards so that it's almost pointing directly at the sun. The switchbacks only seem to occur close to the sun (within Mercury's orbit), so scientists could never have observed them without the Parker probe. "These are great clues, and now we can go look at the surface of the sun and figure out what's causing those [bursts] and launching them up into space," Kasper said. Parker confirmed that there's a dust-free zone around the sun Scientists have long suspected that the sun is surrounded by an area without nay cosmic dust — the tiny crumbs of planets and asteroids that float through space and fall into stars' orbits. That's because the sun's heat should vaporize any solid dust that gets too close. For the first time, Parker flew close enough to the sun to provide evidence that such a dust-free zone exists. It observed that the dust does indeed get thinner closer to the sun. Still, this zone wasn't quite what scientists expected. "What was a bit of a surprise is that the dust decrease is very smooth," Russell Howard, another astrophysicist working with the probe, said in the call. "We don't see any sudden decreases indicating that some material has evaporated." That will be another mystery to prod as the spacecraft gets closer to the sun. 6 more years and 21 more flybys More knowledge about solar wind and the sun's magnetic field could help scientists better protect astronauts and spacecraft from two types of violent space weather: energetic particle storms and coronal mass ejections. In energetic particle storms, events on the sun send out floods of the ions and electrons that make up solar wind. These particles travel at almost the speed of light, which makes them nearly impossible to foresee. They can reach Earth in under half an hour and damage spacecraft electronics. This can be especially dangerous to astronauts traveling far from Earth. In a coronal mass ejection, the sun sends billions of tons of coronal material hurtling into space. Such an explosion could cause mass damage to Earth's power grids and pipelines. Over the next six years, Parker will make close approaches to the sun 21 more times, getting closer and closer. In its final pass, it will fly within 4 million miles of the sun's surface. During each fly-by, the probe will gather more data that could answer physicists' questions about the sun's corona and solar wind. "As we get closer, we'll be right in the sources of the heat, the sources of the acceleration of particles, and of course those amazing eruptions," Nicola Fox, NASA's director of heliophysics, said in the call. "Even with what we have now, we already know that we will need to adjust the model used to understand the sun."SEE ALSO: NASA's plans for the 2020s include landing humans on the moon, detecting quakes on Mars, and defending Earth from deadly asteroids DON'T MISS: A handful of recent discoveries has transformed our understanding of Earth-like planets in the galaxy. Here's why Earths might be common. Join the conversation about this story » NOW WATCH: What if the Earth stopped orbiting the Sun?