That New Kind of Aurora Called “Steve”? Turns Out, it Isn’t an Aurora at All

Since time immemorial, people living in the Arctic Circle or the southern tip of Chile have looked up at the night sky and been dazzled by the sight of the auroras. Known as the Aurora Borealis in the north and Aurora Australis in the south (the “Northern Lights” and “Southern Lights”, respectively) these dazzling displays are the result of interactions in the ionosphere between charged solar particles and the Earth’s magnetic field.

However, in recent decades, amateur photographers began capturing photos of what appeared to be a new type of aurora – known as STEVE. In 2016, it was brought to the attention of scientists, who began trying to explain what accounted for the strange ribbons of purple and white light in the night sky. According to a new study, STEVE is not an aurora at all, but an entirely new celestial phenomenon.

The study recently appeared in the Geophysical Research Letters under the title “On the Origin of STEVE: Particle Precipitation or Ionospheric Skyglow?“. The study was conducted by a team of researchers from the Department of Physics and Astronomy from the University of Calgary, which was led by Beatriz Gallardo-Lacourt (a postdoctoral associate), and included Yukitoshi Nishimura – an assistant researcher of the Department of Atmospheric and Oceanic Sciences at the University of California.

STEVE, as imaged by Dave Markel in the skies above northern Canada. Copyright: davemarkelphoto

STEVE first became known to scientists thanks to the efforts of the Alberta Aurora Chasers (AAC), who occasionally noticed these bright, thin streams of white and purple light running from east to west in the night sky when photographing the aurora. Unlike auroras, which are visible whenever viewing conditions are right, STEVE was only visible a few times a year and could only be seen at high latitudes.

Initially, the photographers thought the light ribbons were the result of excited protons, but these fall outside the range of wavelengths that normal cameras can see and require special equipment to image. The AAC eventually named the light ribbons “Steve” – a reference to the 2006 film Over the Hedge. By 2016, Steve was brought to the attention of scientists, who turned the name into a backronym for Strong Thermal Emission Velocity Enhancement.

For their study, the research team analyzed a STEVE event that took place on March 28th, 2008, to see if it was produced in a similar fashion to an aurora. To this end, they considered previous research that was conducted using satellites and ground-based observatories, which included the first study on STEVE (published in March of 2018) conducted by a team of NASA-led scientists (of which Gallardo-Lacourt was a co-author).

This study indicated the presence of a stream of fast-moving ions and super-hot electrons passing through the ionosphere where STEVE was observed. While the research team suspected the two were connected, they could not conclusively state that the ions and electrons were responsible for producing it. Building on this, Gallardo-Lacourt and her colleagues analyzed the STEVE event that took place in March of 2008.

Rays of aurora borealis reach 60 miles and higher over the Pacific Northwest on Jan. 20, 2016 in this photo taken by astronauts Scott Kelly and Tim Peake from the International Space Station. Credit: NASA

They began by using images from ground-based cameras that record auroras over North America, which they then combined with data from the National Oceanic and Atmospheric Administration‘s (NOAA) Polar Orbiting Environmental Satellite 17 (POES-17). This satellite, which can measure the precipitation of charged particles into the ionosphere, was passing directly over the ground-based cameras during the STEVE event.

What they found was that the POES-17 satellite detected no charged particles raining down on the ionosphere during the event. This means that STEVE is not likely to be caused by the same mechanism as an aurora, and is therefore an entirely new type of optical phenomenon – which the team refer to as “skyglow”. As Gallardo-Lacourt explained in an AGU press release:

“Our main conclusion is that STEVE is not an aurora. So right now, we know very little about it. And that’s the cool thing, because this has been known by photographers for decades. But for the scientists, it’s completely unknown.”

Looking ahead, Galladro-Lacourt and her colleagues seek to test the conclusions of the NASA-led study. In short, they want to find out whether the streams of fast ions and hot electrons that were detected in the ionosphere are responsible for STEVE, or if the light is being produced higher up in the atmosphere. One thing is for certain though; for aurora chasers, evening sky-watching has become more interesting!

Further Reading: AGU

Watch the Sun to Know When We’re Going to Have Killer Auroras

To the naked eye, the Sun puts out energy in a continual, steady state, unchanged through human history. (Don’t look at the sun with your naked eye!) But telescopes tuned to different parts of the electromagnetic spectrum reveal the Sun’s true nature: A shifting, dynamic ball of plasma with a turbulent life. And that dynamic, magnetic turbulence creates space weather.

Space weather is mostly invisible to us, but the part we can see is one of nature’s most stunning displays, the auroras. The aurora’s are triggered when energetic material from the Sun slams into the Earth’s magnetic field. The result is the shimmering, shifting bands of color seen at northern and southern latitudes, also known as the northern and southern lights.

This image of the northern lights over Canada was taken by a crew member on board the ISS in Sept. 2017. Image: NASA

There are two things that can cause auroras, but both start with the Sun. The first involves solar flares. Highly-active regions on the Sun’s surface produce more solar flares, which are sudden, localized increase in the Sun’s brightness. Often, but not always, a solar flare is coupled with a coronal mass ejection (CME).

A coronal mass ejection is a discharge of matter and electromagnetic radiation into space. This magnetized plasma is mostly protons and electrons. The CME ejection often just disperses into space, but not always. If it’s aimed in the direction of the Earth, chances are we get increased auroral activity.

The second cause of auroras are coronal holes on the Sun’s surface. A coronal hole is a region on the surface of the Sun that is cooler and less dense than surrounding areas. Coronal holes are the source of fast-moving streams of material from the Sun.

Whether it’s from an active region on the Sun full of solar flares, or whether it’s from a coronal hole, the result is the same. When the discharge from the Sun strikes the charged particles in our own magnetosphere with enough force, both can be forced into our upper atmosphere. As they reach the atmosphere, they give up their energy. This causes constituents in our atmosphere to emit light. Anyone who has witnessed an aurora knows just how striking that light can be. The shifting and shimmering patterns of light are mesmerizing.

The auroras occur in a region called the auroral oval, which is biased towards the night side of the Earth. This oval is expanded by stronger solar emissions. So when we watch the surface of the Sun for increased activity, we can often predict brighter auroras which will be more visible in southern latitudes, due to the expansion of the auroral oval.

This photo is of the aurora australis over New Zealand. Image: Paul Stewart, Public Domain, CC 1.0 Universal.

Something happening on the surface of the Sun in the last couple days could signal increased auroras on Earth, tonight and tomorrow (March 28th, 29th). A feature called a trans-equatorial coronal hole is facing Earth, which could mean that a strong solar wind is about to hit us. If it does, look north or south at night, depending on where your live, to see the auroras.

Of course, auroras are only one aspect of space weather. They’re like rainbows, because they’re very pretty, and they’re harmless. But space weather can be much more powerful, and can produce much greater effects than mere auroras. That’s why there’s a growing effort to be able to predict space weather by watching the Sun.

A powerful enough solar storm can produce a CME strong enough to damage things like power systems, navigation systems, communications systems, and satellites. The Carrington Event in 1859 was one such event. It produced one of the largest solar storms on record.

That storm occurred on September 1st and 2nd, 1859. It was preceded by an increase in sun spots, and the flare that accompanied the CME was observed by astronomers. The auroras caused by this storm were seen as far south as the Caribbean.

Sunspots are dark areas on the surface of the Sun that are cooler than the surrounding areas. They form where magnetic fields are particularly strong. The highly active magnetic fields near sunspots often cause solar flares. Image: NASA/SDO/AIA/HMI/Goddard Space Flight Center

The same storm today, in our modern technological world, would wreak havoc. In 2012, we almost found out exactly how damaging a storm of that magnitude could be. A pair of CMEs as powerful as the Carrington Event came barreling towards Earth, but narrowly missed us.

We’ve learned a lot about the Sun and solar storms since 1859. We now know that the Sun’s activity is cyclical. Every 11 years, the Sun goes through its cycle, from solar maximum to solar minimum. The maximum and minimum correspond to periods of maximum sunspot activity and minimum sunspot activity. The 11 year cycle goes from minimum to minimum. When the Sun’s activity is at its minimum in the cycle, most CMEs come from coronal holes.

NASA’s Solar Dynamics Observatory (SDO), and the combined ESA/NASA Solar and Heliospheric Observatory (SOHO) are space observatories tasked with studying the Sun. The SDO focuses on the Sun and its magnetic field, and how changes influence life on Earth and our technological systems. SOHO studies the structure and behavior of the solar interior, and also how the solar wind is produced.

Several different websites allow anyone to check in on the behavior of the Sun, and to see what space weather might be coming our way. The NOAA’s Space Weather Prediction Center has an array of data and visualizations to help understand what’s going on with the Sun. Scroll down to the Aurora forecast to watch a visualization of expected auroral activity.

NASA’s Space Weather site contains all kinds of news about NASA missions and discoveries around space weather. SpaceWeatherLive.com is a volunteer run site that provides real-time info on space weather. You can even sign up to receive alerts for upcoming auroras and other solar activity.

NASA’s Parker Solar Probe Will Touch the Sun — So Can You

NASA’s Parker Solar Probe will launch this summer and study both the solar wind and unanswered questions about the Sun’s sizzling corona. Credit: NASA

How would you like to take an all-expenses-paid trip to the Sun? NASA is inviting people around the world to submit their names to be placed on a microchip aboard the Parker Solar Probe mission that will launch this summer. As the spacecraft dips into the blazing hot solar corona your name will go along for the ride. To sign up, submit your name and e-mail. After a confirming e-mail, your digital “seat” will be booked. You can even print off a spiffy ticket. Submissions will be accepted until April 27, so come on down!

Step right up! Head over before April 27 to put a little (intense) sunshine in your life. Click the image to go there. Credit: NASA

The Parker Solar Probe is the size of a small car and named for Prof. Eugene Parker, a 90-year-old American astrophysicist who in 1958 discovered the solar wind. It’s the first time that NASA has named a spacecraft after a living person. The Parker probe will launch between July 31 and August 19 but not immediately head for the Sun. Instead it will make a beeline for Venus for the first of seven flybys. Each gravity assist will slow the craft down and reshape its orbit (see below), so it later can pass extremely close to the Sun. The first flyby is slated for late September.

When heading to faraway places, NASA typically will fly by a planet to increase the spacecraft’s speed by robbing energy from its orbital motion. But a probe can also approach a planet on a different trajectory to slow itself down or reconfigure its orbit.

The spacecraft will swing well within the orbit of Mercury and more than seven times closer than any spacecraft has come to the Sun before. When closest at just 3.9 million miles (6.3 million km), it will pass through the Sun’s outer atmosphere called the corona and be subjected to temperatures around 2,500°F (1,377°C). The primary science goals for the mission are to trace how energy and heat move through the solar corona and to explore what accelerates the solar wind as well as solar energetic particles.

The Parker Solar Probe will use seven Venus flybys over nearly seven years to gradually shrink its orbit around the Sun, coming as close as 3.7 million miles (5.9 million km), well within the orbit of Mercury. Closest approaches (called perihelia) will happen in late December 2024 and the first half of 2025 before the mission ends. Credit: NASA

The vagaries of the solar wind, a steady flow of particles that “blows” from the Sun’s corona at more than million miles an hour, can touch Earth in beautiful ways as when it energizes the aurora borealis. But it can also damage spacecraft electronics and poorly protected power grids on the ground. That’s why scientists want to know more about how the corona works, in particular why it’s so much hotter than the surface of the Sun — temperatures there are several million degrees.

During the probe’s closest approach, the Sun’s apparent diameter will span 14° of sky. Compare that to the ½° Sun we see from Earth. Can you imagine how hot the Sun’s rays would be if it were this large from Earth? Life as we know it would be over. Wikipedia / CC BY-SA 3.0

As you can imagine, it gets really, really hot near the Sun, so you’ve got to take special precautions. To perform its mission, the spacecraft and instruments will be protected from the Sun’s heat by a 4.5-inch-thick carbon-composite shield, which will keep the four instrument suites designed to study magnetic fields, plasma and energetic particles, and take pictures of the solar wind, all at room temperature.

Similar to how the Juno probe makes close passes over Jupiter’s radiation-fraught polar regions and then loops back out to safer ground, the Parker probe will make 24 orbits around the Sun, spending a relatively short amount of face to face time with our star. At closest approach, the spacecraft will be tearing along at about 430,000 mph, fast enough to get from Washington, D.C., to Tokyo in under a minute, and will temporarily become the fastest manmade object. The current speed record is held by Helios-B when it swung around the Sun at 156,600 mph (70 km/sec) on April 17, 1976.

A composite of the August 21, 2017 total solar eclipse showing the Sun’s spectacular corona. Astronomers still are sure why it’s so much hotter than the 10,000°F solar surface (photosphere). Theories include a microflares or magnetic waves that travel up from deep inside the Sun. Credit and copyright: Alan Dyer / amazingsky.com

Many of you saw last August’s total solar eclipse and marveled at the beauty of the corona, that luminous spider web of light around Moon’s blackened disk. When closest to the Sun at perihelion the Parker probe will fly to within 9 solar radii (4.5 solar diameters) of its surface. That’s just about where the edge of the furthest visual extent of the corona merged with the blue sky that fine day, and that’s where Parker will be!

Big Solar Storm Coming Our Way, Now’s Your Chance to See Auroras

X9.3 Flare blasts off the Sun. Image credit: NASA/GSFC/SDO

An X9.3 class solar flare flashes in the middle of the Sun on Sept. 6, 2017. Credit:NASA/GSFC/SDO
An X9.3 class solar flare flashes in the middle of the Sun on Sept. 6, 2017. Credit:NASA/GSFC/SDO

If you’re still riding that high from seeing the recent total solar eclipse and you want to keep the party going, now’s your chance to see another of the night sky’s wonders: an aurora. That said, a totally full Moon is going to try and wreck the party.

NASA announced that two powerful flares were just emitted on the surface of the Sun, casting coronal mass ejections in our direction. Over the course of the next couple of days, this should generate aurora activity in the sky outside the regular viewing areas. In other words, if you normally don’t see the Northern Lights where you live, you might want to spend a few hours outside tonight and tomorrow. Look up, you might see something.

The first flare, an X2.2 event, peaked on September 6 at 5:10 am EDT and the second X9.3 flare went off at 8:02 am. Both of which came from the sunspot group AR 2673. If you’ve still got those eclipse glasses, take a look at the Sun, and you should be able to see the sunspot group right now. There are two groups of sunspots close to one another, AR 2673 and AR 2674. This follows up the X4 flare emitted on September 4th.

Solar astronomers measure flares using a similar scale to other natural events, with a series of designations. The smallest are A-class, then B, C, M and finally X. Each level within the rating accounts for double the strength; it’s exponential. So, and X2 is twice as powerful as an X1, etc. The most powerful flare ever recorded was an X28 in 2003, so today’s flare is still comparatively weak to that monster.

Here's the flare in visible and ultraviolet. Credit: NASA/GSFC/SDO
Here’s the flare in visible and ultraviolet. Credit: NASA/GSFC/SDO

But, measuring in at X9.3, today’s flare is the strongest in almost a decade. The last one this strong was back in 2008. And NOAA is predicting that this flare could cause radio blackouts across the sun-facing side of the Earth. If you’re out at sea and depending on your radio transmissions, don’t be surprised if you’re getting a lot of static today.

How do you stand the best chance of seeing auroras? My favorite tool comes from NOAA’s 3-day aurora forecast. It shows you a 3-day predictive simulation for what the solar storm should do as it buffets the Earth’s magnetosphere. You can run the simulation backwards and forwards, and you’re looking glowing green areas to come across your part of the world.

But even if it doesn’t look like you’re going to see the auroras, I still think it’s worth trying. Even if you don’t get an aurora directly overhead, you can sometimes see it on the horizon, and it can be surprisingly beautiful.

Here’s my timelapse video of auroras on the horizon.

The big problem, of course, is the Moon. Tonight is also a full Moon, which means that awful glowing ball is going to rise just after sunset and blaze across the sky all night. You’re going to have a rough time seeing all but the brightest auroras. But I still think it’s worth trying.

If you want to maximize your chances of seeing an aurora, check out the Space Weather site on a regular basis. There are also services that’ll send you a text message when there’s a powerful aurora going on in your area (just Google “aurora alert text messages”. And of course, there are handy apps that’ll make your phone beep boop when there are auroras overhead. I use an app called Aurora Alert.

We’ve had three powerful flares in the last couple of days, which means that the Sun is feeling a little frisky. There could be more, and they could happen after the full Moon is over, and we’ve got some alone time with the dark sky. So stay on top of the current space weather, spend time outside, and keep your eyes on the sky. You might get a shot at seeing an aurora.

And once you’ve seen one, you’ll be hooked.

Source: NASA News Release

Meet Steve, A Most Peculiar Aurora

Nicknamed Steve, this unusual aurora feature is a 15.5-mile-wide (25 km) ribbon of hot gas flowing westward at about 13,300 mph, more than 600 times faster than the surrounding air. The photo was taken last fall. Copyright: Instagram.com/davemarkelphoto

This remarkable image was captured last fall by Dave Markel, a photographer based in Kamloops, British Columbia. Later, aurora researcher Eric Donovan of the University of Calgary, discovered Markel’s strange ribbon of light while looking through photos of the northern lights on social media. Knowing he’d found something unusual, Donovan worked sifted through data from the European Space Agency’s Swarm magnetic field mission to try and understand the nature of the phenomenon.

Swarm is ESA’s first constellation of Earth observation satellites designed to measure the magnetic signals from Earth’s core, mantle, crust, oceans, ionosphere and magnetosphere, providing data that will allow scientists to study the complexities of our protective magnetic field. Credit: ESA/AOES Medialab

Launched on 22 November 2013, three identical Swarm satellites orbit the Earth measuring the magnetic fields that stem from Earth’s core, mantle, crust and oceans, as well as from the ionosphere and magnetosphere. Speaking at the recent Swarm science meeting in Canada, Donovan explained how this new finding couldn’t have happened 20 years ago when he started to study the aurora.

A beautiful aurora featuring green arcs near the horizon and many parallel rays lights up the northern sky last October. A small meteor appears to the right of center. Credit: Bob King

While the shimmering, eerie, light display of auroras might be beautiful and captivating, they’re also a visual reminder that Earth is connected electrically and magnetically to the Sun. The more we know about the aurora, the greater our understanding of that connection and how it affects everything from satellites to power grids to electrically-induced corrosion of oil pipelines.

“In 1997 we had just one all-sky imager in North America to observe the aurora borealis from the ground,” said Prof. Donovan.  “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. Now we have many more all-sky imagers and satellite missions like Swarm so we get more than 100 a night.”

The Suomi NPP satellite photographed this view of the aurora on December 22, 2016, when the northern lights stretched across northern Canada. Credit: NASA Earth Observatory image by Jesse Allen / Suomi National Polar-orbiting Partnership. Colorized and labeled by the author

And that’s where sharing photos and observations on social media can play an important role. Sites like the Great Lakes Aurora Hunters and Aurorasaurus serve as clearinghouses for observers to report auroral displays.  Aurorasaurus connects citizen scientists to scientists and searches Twitter feeds for instances of the word ‘aurora,’ so skywatchers and scientists alike know the real-time extent of the auroral oval.

At a recent talk, Prof. Donovan met members the popular Facebook group Alberta Aurora Chasers. Looking at their photos, he came across the purple streak Markel and others had photographed which they’d been referring to as a “proton arc.” But such a feature, caused by hydrogen emission in the upper atmosphere, is too faint to be seen with the naked eye. Donovan knew it was something else, but what?Someone suggested “Steve.” Hey, why not?

Aurora researchers now us a network of all-sky cameras and multiple satellites to keep track of the ever-shifting aurora. Click to see the video. Credit: University of Calgary

While the group kept watch for the Steve’s return,  Donovan and colleagues looked through data from the Swarm mission and his network of all-sky cameras. Before long he was able to match a ground sighting of streak to an overpass of one of the three Swarm satellites.

“As the satellite flew straight though Steve, data from the electric field instrument showed very clear changes,” said Donovan.

“The temperature 186 miles (300 km) above Earth’s surface jumped by 3000°C and the data revealed a 15.5-mile-wide (25 km) ribbon of gas flowing westwards at about 6 km/second compared to a speed of about 10 meters/second either side of the ribbon. A friend of mine compared it to a fluorescent light without the glass.

Little did I know I’d met Steve back on May 18, 1990 in this remarkable, narrow arc that stretched from the northwestern horizon to the southeastern. To the eye, a “wind” of vague forms pulsed through the arc. The Big Dipper stands vertically at right. Credit: Bob King

It turns out that these high-speed “rivers” of glowing auroral gas are much more common than we’d thought, and that in no small measure because of the efforts of an army of skywatchers and aurora photographers who keep watch for that telltale green glow in the northern sky.

I spoke to Steve’s keeper, Dave Markel, via e-mail yesterday and he described what the arc looked like to his eyes:

“It’s similar to the image just not as intense. It looks like a massive contrail moving rapidly across the sky. This one lasted almost an hour and ran in an arc almost perfectly east to west. I was directly below it but often there are green pickets (parallel streaks of aurora) rising above the streak.”

This is the same May 18, 1990 streak as above but the eastern half. The bright star Arcturus is visible at upper right. Wish I’d had a fisheye! Credit: Bob King

I know whereof Dave speaks because thanks to his photo and Prof. Donovan’s research, I realize I’ve seen and photographed Steve, too! In decades of aurora watching I’ve only seen this rare streak a handful of times. On most of those occasions, there was either no other aurora visible or minor activity in the northern sky. The narrow arc, which lasted for an hour or so, pulsed and flowed with light and occasionally, Markel’s “pickets” were visible. Back in May 1990 I had a camera on hand to get a picture.

Goes to show, you never know what you might see when you poke your head out for a look. Keep a lookout when aurora’s expected and maybe you’ll get to meet Steve, too.

Hubble Sees Intense Auroras on Uranus

This is a composite image of Uranus by Voyager 2 and two different observations made by Hubble — one for the ring and one for the auroras. These auroras occurred in the planet’s southern latitudes near the planet’s south magnetic pole. Like Jupiter and Saturn, hydrogen atoms excited by blasts of the solar wind are the cause for the glowing white patches seen in both photos. Credit: NASA/ESA

Earth doesn’t have a corner on auroras. Venus, Mars, Jupiter, Saturn, Uranus and Neptune have their own distinctive versions. Jupiter’s are massive and powerful; Martian auroras patchy and weak.

Auroras are caused by streams of charged particles like electrons that originate with solar winds and in the case of Jupiter, volcanic gases spewed by the moon Io. Whether solar particles or volcanic sulfur, the material gets caught in powerful magnetic fields surrounding a planet and channeled into the upper atmosphere. There, the particles interact with atmospheric gases such as oxygen or nitrogen and spectacular bursts of light result. With Jupiter, Saturn and Uranus excited hydrogen is responsible for the show.

These composite images show Uranian auroras, which scientists caught glimpses of through the Hubble in 2011. In the left image, you can clearly see how the aurora stands high above the planet’s denser atmosphere. These photos combine Hubble pictures made in UV and visible light by Hubble with photos of Uranus’ disk from the Voyager 2 and a third image of the rings from the Gemini Observatory in Hawaii and Chile. The auroras are located close to the planet’s north magnetic pole, making these northern lights.
Credit: NASA, ESA, and L. Lamy (Observatory of Paris, CNRS, CNES)

Auroras on Earth, Jupiter and Saturn have been well-studied but not so on the ice-giant planet Uranus. In 2011, the Hubble Space Telescope took the first-ever image of the auroras on Uranus. Then in 2012 and 2014 a team from the Paris Observatory took a second look at the auroras in ultraviolet light using the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.

From left: Auroras on Earth (southern auroral oval is seen over Antarctica), Jupiter and Saturn. In each case, the rings of permanent aurora are centered on their planets’ magnetic poles which aren’t too far from the geographic poles, unlike topsy-turvy Uranus. Credit: NASA

Two powerful bursts of solar wind traveling from the sun to Uranus stoked the most intense auroras ever observed on the planet in those years. By watching the auroras over time, the team discovered that these powerful shimmering regions rotate with the planet. They also re-discovered Uranus’ long-lost magnetic poles, which were lost shortly after their discovery by Voyager 2 in 1986 due to uncertainties in measurements and the fact that the planet’s surface is practically featureless. Imagine trying to find the north and south poles of a cue ball. Yeah, something like that.

In both photos, the auroras look like glowing dots or patchy spots. Because Uranus’ magnetic field is inclined 59° to its spin axis (remember, this is the planet that rotates on its side!) , the auroral spots appear far from the planet’s north and south geographic poles. They almost look random but of course they’re not. In 2011, the spots lie close to the planet’s north magnetic pole, and in 2012 and 2014, near the south magnetic pole — just like auroras on Earth.

An auroral display can last for hours here on the home planet, but in the case of the 2011 Uranian lights, they pulsed for just minutes before fading away.

Want to know more? Read the team’s findings in detail here.

NASA Fires a Rocket into the Northern Lights, for Science!

Not only is it aurora season in Alaska, its sounding rocket season! NASA started launching a series of five sounding rockets from the Poker Flat Research Range in Alaska to study the aurora. The first of these rockets for this year, a Black Brant IX, was launched in the early morning hours of February 22, 2017.

The instrument on board was an Ionospheric Structuring: In Situ and Groundbased Low Altitude StudieS (ISINGLASS) instrumented payload, which studies the structure of an aurora.

The Black Brant IX sounding rocket carried instruments to an altitude of 225 miles as part of the Ionospheric Structuring: In Situ and Groundbased Low Altitude StudieS or ISINGLASS mission. Credit: NASA/Terry Zaperach.

This is not the first sounding rocket flight from Poker Flats to launch into an aurora. Starting in 2009, this research has been taking place to help refine current models of aurora structure, and provide insight on the high-frequency waves and turbulence generated by aurorae. This helps us to better understand the space weather caused by the charged particles that come from the Sun and how it impacts Earth’s lower atmosphere and ionosphere.

“The visible light produced in the atmosphere as aurora is the last step of a chain of processes connecting the solar wind to the atmosphere,” said Kristina Lynch, ISINGLASS principal investigator from Dartmouth College. “We are seeking to understand what structure in these visible signatures can tell us about the electrodynamics of processes higher up.”

While humans don’t feel any of these effects directly, the electronic systems in our satellites do, and as our reliance on satellite technologies grow, researchers want to have all the data they can to help avert problems than can be caused by space weather.

The rocket sent a stream of real-time data back before landing about 200 miles downrange shortly after the launch.

The launch window for the remaining rockets runs through March 3. ISINGLASS will fly into what is known as a dynamic Alfenic curtain, which is a form of electromagnetic energy thought to be a key driver of “discrete” aurora – the typical, well-defined band of shimmering lights about six miles thick and stretching east to west from horizon to horizon.

NASA says that the five launches in the 2017 sounding rocket campaign will add to our body of information about this space through which our spacecraft and astronauts travel near Earth. By studying the interaction of the sun and its solar wind with Earth’s upper atmosphere, scientists are also able to apply the knowledge to other planetary bodies — helping us understand these interactions throughout the universe as well.

Here’s an infographic from NASA about the 2017 sounding rocket launches from Poker Flats:

Read more: NASA

Northern Lights by Drone? You Won’t Believe Your Eyes


Northern lights over Iceland filmed by Icelandic photographer Oli Haukur using a drone. Don’t forget to expand the screen.

I knew the era of real-time northern lights video was upon us. I just didn’t think drones would get into the act this soon. What was I thinking? They’re perfect for the job! If watching the aurora ever made you feel like you could fly, well now you can in Oli Haukur’s moving, real-time footage of an amazing aurora display filmed by drone.

Oli Haukur operates the drone and camera during a test run. Credit: Oli Hauku / OZZO Photography
Oli Haukur operates the drone and camera during a test run. Credit: Oli Hauku / OZZO Photography

Haukur hooked up a Sony a7S II digital camera and ultra-wide Sigma 20mm f/1.4 lens onto his DJI Matrice 600 hexacopter. The light from the gibbous moon illuminates the rugged shoreline and crashing waves of the Reykjanes Peninsula (The Steamy Peninsula) as while green curtains of aurora flicker above.

The Sony camera is shown attached to the drone. To capture the aurora, Haukur used a fast lens, high ISO and set the frame rate to 25 frames per second (fps) or 1/25th of a second per frame. Credit: Oli Haukur / OZZO Photography
The Sony camera is shown attached to the drone. To capture the aurora, Haukur used a fast lens, high ISO and set the frame rate to 25 frames per second (fps) or 1/25th of a second per frame. Credit: Oli Haukur / OZZO Photography

When the camera ascends over a sea stack, you can see gulls take off below, surprised by the mechanical bird buzzing just above their heads. Breathtaking. You might notice at the same time a flash of light — this is from the lighthouse beacon seen earlier in the video.

To capture his the footage, Haukur used a “fast” lens (one that needs only a small amount of light to make a picture) and an ISO of 25,600. The camera is capable of ISO 400,000, but the lower ISO provided greater resolution and color quality.

Moonlight provided all the light needed to bring out the landscape.

The drone used to make the night flight. Credit: Oli Haukur
The drone used to make the night flight and aurora recording is seen up close on takeoff. Haukur, of Rejkyavik, Iceland, works as a freelance photographer and filmmaker as well as providing professional drone services in that country. Credit: Oli Haukur / OZZO Photography

Remember when ISO 1600 or 3200 was as far you dared to go before the image turned to a grainy mush? Last year Canon released a camera that can literally see in the dark with a top ISO over 4,000,000! There’s no question we’ll be seeing more live aurora and drone aurora video in the coming months. Haukur plans additional shoots this winter and early next spring. Living in Iceland, which lies almost directly beneath the permanent auroral oval, you can schedule these sort of things!

Am I allowed one tiny criticism? I want more — a minute and a half is barely enough! Haukur shot plenty but released only a taste to social media to prove it could be done and share the joy. Let’s hope he compiles the rest and makes it available for us to lose our selves in soon.

Space Weather Causing Martian Atmospherics

A curious plume-like feature was observed on Mars on 17 May 1997 by the Hubble Space Telescope. It is similar to the features detected by amateur astronomers in 2012, although appeared in a different location. Credit: JPL/NASA/STScI
A curious plume-like feature was observed on Mars on May 17, 1997 by the Hubble Space Telescope. It is similar to the features detected by amateur astronomers in 2012, although appeared in a different location. Credit: JPL/NASA/STScI

Strange plumes in Mars’ atmosphere first recorded by amateur astronomers four year ago have planetary scientists still scratching their heads. But new data from European Space Agency’s orbiting Mars Express points to coronal mass ejections from the Sun as the culprit.

Mystery plume in Mars’ southern hemisphere photographed by amateur astronomer Wayne Jaeschke on March 20, 2012. The feature extended between 310-620 miles and lasted for about 10 days.
Mystery plume in Mars’ southern hemisphere photographed and animated by amateur astronomer Wayne Jaeschke on March 20, 2012. The feature lasted for about 10 days. Credit: Wayne Jaeschke

On two occasions in 2012 amateurs photographed cloud-like features rising to altitudes of over 155 miles (250 km) above the same region of Mars. By comparison, similar features seen in the past haven’t exceeded 62 miles (100 km). On March 20th of that year, the cloud developed in less than 10 hours, covered an area of up to 620 x 310 miles (1000 x 500 kilometers), and remained visible for around 10 days.

Back then astronomers hypothesized that ice crystals or even dust whirled high into the Martian atmosphere by seasonal winds might be the cause. However, the extreme altitude is far higher than where typical clouds of frozen carbon dioxide and water are thought to be able to form.

Indeed at those altitudes, we’ve entered Mars’ ionosphere, a rarified region where what air there is has been ionized by solar radiation. At Earth, charged particles from the Sun follow the planet’s global magnetic lines of force into the upper atmosphere to spark the aurora borealis. Might the strange features observed be Martian auroras linked to regions on the surface with stronger-than-usual magnetic fields?

Mars has magnetized rocks in its crust that create localized, patchy magnetic fields (left). In the illustration at right, we see how those fields extend into space above the rocks. At their tops, auroras can form. Credit: NASA
Mars has magnetized rocks in its crust that create localized, patchy magnetic fields (left). In the illustration at right, we see how those fields extend into space above the rocks. At their tops, auroras can form. Credit: NASA

Once upon a very long time ago, Mars may have had a global magnetic field generated by electrical currents in a liquid iron-nickel core much like the Earth’s does today. In the current era, the Red Planet has only residual fields centered over regions of magnetic rocks in its crust.

Copyright: W. Jaeschke and D. Parker The top image shows the location of the mysterious plume on Mars, identified within the yellow circle (top image, south is up), along with different views of the changing plume morphology taken by W. Jaeschke and D. Parker on 21 March 21 2012.
The top image shows the location of the mysterious plume on Mars, identified within the yellow circle (top image, south is up), along with different views of the changing plume morphology on March 21, 2012. Copyright: W. Jaeschke and D. Parker

Instead of a single, planet-wide field that funnels particles from the Sun into the atmosphere to generate auroras, Mars is peppered with pockets of magnetism, each potentially capable of connecting with the wind of particles from the Sun to spark a modest display of the “northern lights.” Auroras were first discovered on Mars in 2004 by the Mars Express orbiter, but they’re faint compared to the plumes, which were too bright to be considered auroras.

Still, this was a step in the right direction. What was needed was some hard data of a possible Sun-Earth interaction which scientists ultimately found when they looked into plasma and solar wind measurements collected by Mars Express at the time. David Andrews of the Swedish Institute of Space Physics, lead author of a recent paper reporting the Mars Express results, found evidence for a large coronal mass ejection or CME from the Sun striking the martian atmosphere in the right place and at around the right time.

Examples of Earth-based observations of the mysterious plume seen on 21 March 2012 (top right) and of Mars Express solar wind observations during March and April 2012 (bottom right).
Earth-based observations of the plume on March 21, 2012 (top right) and of Mars Express solar wind observations during March and April 2012 (bottom right). The left-hand graphics show Mars as seen by Mars Express. Green represents the planet’s dayside and gray, the nightside. Magnetic areas of the crust are shown in blue and red. The white box indicates the area in which the plume observations were made. Together, these graphics show that the amateur observations were made during the martian daytime, along the dawn terminator, while the spacecraft observations were made along the dusk terminator, approximately half a martian ‘day’ later.The black line on Mars is the ground track of the Mars Express orbiter. The plot on the lower right shows Mars Express’s solar wind measurements. The peaks marked by the horizontal blue line indicate the increase in the solar wind properties as a result of the impact of the coronal mass ejection. Credit: Copyright: visual images: D. Parker (large Mars image and bottom inset) & W. Jaeschke (top inset). All other graphics courtesy D. Andrews

CMEs are enormous explosions of hot solar plasma — a soup of electrons and protons — entwined with magnetic fields that blast off the Sun and can touch off geomagnetic storms and auroras when they encounter the Earth and other planets.

“Our plasma observations tell us that there was a space weather event large enough to impact Mars and increase the escape of plasma from the planet’s atmosphere,” said Andrews. Indeed, the plume was seen along the day–night boundary, over a region of known strong crustal magnetic fields.

Locations of 19 auroral detections (white circles) made by the SPICAM instrument on Mars Express during 113 nightside orbits between 2004 and 2014, over locations already known to be associated with residual crustal magnetism. The data is superimposed on the magnetic field line structure (from NASA’s Mars Global Surveyor) where red indicates closed magnetic field lines, grading through yellow, green and blue to open field lines in purple. The auroral emissions are very short-lived, they are not seen to repeat in the same locations, and only occur near the boundary between open and closed magnetic field lines. Credit: ESA / Copyright Based on data from J-C. Gérard et al (2015)
Locations of 19 auroral detections (white circles) made by Mars Express during 113 nightside orbits between 2004 and 2014, over locations already known to be associated with residual crustal magnetism. The data is superimposed on the magnetic field line structure (from NASA’s Mars Global Surveyor) where red indicates closed magnetic field lines, grading through yellow, green and blue to open field lines in purple. The auroral emissions are very short-lived, they are not seen to repeat in the same locations. Credit: ESA / Copyright Based on data from J-C. Gérard et al (2015)

But again, a Mars aurora wouldn’t be expected to shine so brightly. That’s why Andrews thinks that the CME prompted a disturbance in the ionosphere large enough to affect dust and ice grains below:

“One idea is that a fast-traveling CME causes a significant perturbation in the ionosphere resulting in dust and ice grains residing at high altitudes in the upper atmosphere being pushed around by the ionospheric plasma and magnetic fields, and then lofted to even higher altitudes by electrical charging,” according to Andrews.

A colossal CME departs the Sun in February 2000. erupting filament lifted off the active solar surface and blasted this enormous bubble of magnetic plasma into space. Credit NASA/ESA/SOHO
A colossal CME, composed of a magnetized cloud of subatomic particles, departs the Sun in February 2000. Credit NASA/ESA/SOHO

With enough dust and ice twinkling high above the planet’s surface, it might be possible for observers on Earth to see the result as a wispy plume of light. Plumes appear to be rare on Mars as a search through the archives has revealed. The only other, seen by the Hubble Space Telescope in May 1997, occurred when a CME was hitting the Earth at the same time. Unfortunately, there’s no information from Mars orbiters at the time about its effect on that planet.

Observers on Earth and orbiters zipping around the Red Planet continue to monitor Mars for recurrences. Scientists also plan to use the webcam on Mars Express for more frequent coverage. Like a dog with a bone, once scientists get a bite on a tasty mystery, they won’t be letting go anytime soon.

Give Mom the Aurora Tonight / Mercury Transit Update

Skywatchers across the northern tier of states, the Midwest and southern Canada were treated to a spectacular display of the aurora borealis last night. More may be on tap for tonight. Credit: Bob King
Skywatchers across the northern tier of states, the Midwest and southern Canada were treated to a spectacular display of the aurora borealis last night. More may be on tap for tonight — in honor of Mother’s Day of course! Credit: Bob King

Simple choices can sometimes lead to dramatic turns of events in our lives. Before turning in for the night last night, I opened the front door for one last look at the night sky. A brighter-than-normal auroral arc arched over the northern horizon. Although no geomagnetic activity had been forecast, there was something about that arc that hinted of possibility.

It was 11:30 at the time, and it would have been easy to go to bed, but I figured one quick drive north for a better look couldn’t hurt. Ten minutes later the sky exploded. The arc subdivided into individual pillars of light that stretched by degrees until they reached the zenith and beyond. Rhythmic ripples of light – much like the regular beat of waves on a beach — pulsed upward through the display. You can’t see a chill going up your spine, but if you could, this is what it would look like.

A coronal aurora twists overhead in this photo taken early on May 8 from near Duluth, Minn. Credit: Bob King
A coronal aurora twists overhead in this photo taken around 12:15 a.m. on May 8 from near Duluth, Minn. What this photo and the others don’t show is how fast parts of the display flashed and flickered. Shapes would form, disappear and reform in seconds. Credit: Bob King

Auroras can be caused by huge eruptions of subatomic particles from the Sun’s corona called CMEs or coronal mass ejections, but they can also be sparked by holes in the solar magnetic canopy. Coronal holes show up as blank regions in photos of the Sun taken in far ultraviolet and X-ray light. Bright magnetic loops restrain the constant leakage of electrons and protons from the Sun called the solar wind. But holes allow these particles to fly away into space at high speed. Last night’s aurora traces its origin back to one of these holes.

Visualization of the solar wind encountering Earth's magnetic "defenses" known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet's nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPL
Both a bar magnet (left) and Earth are surrounded by magnetic fields with north and south poles. Earth’s field is shaped by charged particles – electrons and protons – flowing from the sun called the solar wind. Credit: Andy Washnik (left) and NASA

The subatomic particles in the gusty wind come bundled with their own magnetic field with a plus or positive pole and a minus or negative pole. Recall that an ordinary bar magnet also  has a “+” and “-” pole, and that like poles repel and opposite poles attract. Earth likewise has magnetic poles which anchor a large bubble of magnetism around the planet called the magnetosphere.

Visualization of the solar wind encountering Earth's magnetic "defenses" known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet's nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPL
Visualization of the solar wind encountering Earth’s magnetic “defenses” known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet’s nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPL

Field lines in the magnetosphere — those invisible lines of magnetic force around every magnet — point toward the north pole. When the field lines in the solar wind also point north, there’s little interaction between the two, almost like two magnets repelling one another. But if the cloud’s lines of magnetic force point south, they can link directly into Earth’s magnetic field like two magnets snapping together. Particles, primarily electrons, stream willy-nilly at high speed down Earth’s magnetic field lines like a zillion firefighters zipping down fire poles.  They crash directly into molecules and atoms of oxygen and nitrogen around 60-100 miles overhead, which absorb the energy and then release it moments later in bursts of green and red light.

View of the eastern sky during the peak of this morning's aurora. Credit: Bob King
View of the eastern sky during the peak of this morning’s aurora. Credit: Bob King

So do great forces act on the tiniest of things to produce a vibrant display of northern lights. Last night’s show began at nightfall and lasted into dawn. Good news! The latest forecast calls for another round of aurora tonight from about 7 p.m. to 1 a.m. CDT (0-6 hours UT). Only minor G1 storming (K index =5) is expected, but that was last night’s expectation, too. Like the weather, the aurora can be tricky to pin down. Instead of a G1, we got a G3 or strong storm. No one’s complaining.

So if you’re looking for that perfect last minute Mother’s Day gift, take your mom to a place with a good view of the northern sky and start looking at the end of dusk for activity. Displays often begin with a low, “quiet” arc and amp up from there.

The camera recorded pale purple and red but the primary color visible to the eye was green. Credit: Bob Kin
The camera recorded pale purple, red and green, but the primary color visible to the eye was green. Cameras capture far more color than what the naked eye sees because even faint colors increase in intensity during a time exposure. Details: ISO 800, f/2.8, 13 seconds. Credit: Bob King

Aurora or not, tomorrow features a big event many of us have anticipated for years — the transit of Mercury. You’ll find everything you’ll need to know in this earlier story, but to recap, Mercury will cross directly in front of the Sun during the late morning-early evening for European observers and from around sunrise (or before) through late morning-early afternoon for skywatchers in the Americas. Because the planet is tiny and the Sun deadly bright, you’ll need a small telescope capped with a safe solar filter to watch the event. Remember, never look directly at the Sun at any time.

Nov. 15, 1999 transit of Mercury photographed in UV light by the TRACE satellite. Credit: NASA
Nov. 15, 1999 transit of Mercury photographed in UV light by the TRACE satellite. Credit: NASA

If you’re greeted with cloudy skies or live where the transit can’t be seen, be sure to check out astronomer Gianluca Masi’s live stream of the event. He’ll hook you up starting at 11:00 UT (6 a.m. CDT) tomorrow.

The table below includes the times across the major time zones in the continental U.S. for Monday May 9:

Time Zone Eastern (EDT) Central (CDT) Mountain (MDT) Pacific (PDT)
Transit start 7:12 a.m. 6:12 a.m. 5:12 a.m. Not visible
Mid-transit 10:57 a.m. 9:57 a.m. 8:57 a.m. 7:57 a.m.
Transit end 2:42 p.m. 1:42 p.m. 12:42 p.m. 11:42 a.m.