Every 200,000 to 300,000 years Earth’s magnetic poles reverse. What was once the north pole becomes the south, and vice versa. It’s a time of invisible upheaval.
The last reversal was unusual because it was so long ago. For some reason, the poles have remained oriented the way they are now for about three-quarters of a million years. A new study has revealed some of the detail of that reversal.
The Gray Whale is the 10th largest creature alive today, and the 9 creatures larger than it are all whales, too. Gray Whales are known for their epic migration routes, sometimes covering more than 16,000 km (10,000 miles) on their two-way trips between their feeding grounds and their breeding grounds. Researchers don’t have a complete understanding of how whales navigate these great distances, but some evidence suggests that Earth’s magnetism has something to do with it.
The Sun is not exactly placid, though it appears pretty peaceful in the quick glances we can steal with our naked eyes. In reality though, the Sun is a dynamic, chaotic body, spraying out solar wind and radiation and erupting in great sheets of plasma. Living in a technological society next to all that is a challenge.
In the coming years, a number of will be sent to space for the purpose of answering some of the enduring questions about the cosmos. One of the most pressing is the effect that solar activity and “space weather” events have on planet Earth. By being able to better-predict these, scientists will be able to create better early-warning systems that could prevent damage to Earth’s electrical infrastructure.
This is the purpose of the Solar Orbiter (SolO), an ESA-led mission with strong participation by NASA that launched this morning (Monday, Feb. 10th) from Cape Canaveral, Florida. This is the first “medium-class” mission implemented as part of the ESA’s Cosmic Vision 2015-25 program and will spend the next five years investigating the Sun’s uncharted polar regions to learn more about how the Sun works.
Solar storms powerful enough to wreak havoc on electronic equipment strike Earth every 25 years, according to a new study. And less powerful—yet still dangerous—storms occur every three years or so. This conclusion comes from a team of scientists from the the University of Warwick and the British Antarctic Survey.
These powerful storms can disrupt electronic equipment, including communication equipment, aviation equipment, power grids, and satellites.
Earth’s fleet of satellites is in a vulnerable position. When solar activity increases, high-energy particles are directed toward Earth. Our large fleet is in the direct path of all that energy, which can damage them or render them inoperable. But now we have another tool to help us protect our satellites.
The idea of exploring and colonizing Mars has never been more alive than it is today. Within the next two decades, there are multiple plans to send crewed missions to the Red Planet, and even some highly ambitious plans to begin building a permanent settlement there. Despite the enthusiasm, there are many significant challenges that need to be addressed before any such endeavors can be attempted.
These challenges – which include the effects of low-gravity on the human body, radiation, and the psychological toll of being away from Earth – become all the more pronounced when dealing with permanent bases. To address this, civil engineer Marco Peroni offers a proposal for a modular Martian base (and a spacecraft to deliver it) that would allow for the colonization of Mars while protecting its inhabitants with artificial radiation shielding.
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.
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.
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.
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.
Our Sun regularly pelts the Earth with all kinds of radiation and charged particles. Just how bad can these solar storms get?
In today’s episode, we’re going to remind you how looking outside of the snow globe can inspire your next existential crisis.
You guys remember the Sun right? Look how happy that little fella is. The Sun is our friend! Life started because of the Sun! Oooh, look, the Sun has a baby face! It’s a beautiful, ball of warmth and goodness, lighting up our skies and bringing happiness into our hearts.
It’s a round yellow circle in crayon. Very stable and firmly edged. Occasionally drawn with a orange lion’s mane for coronal effects. Nothing to be afraid, right?
Wake up sheeple. It’s time to pull back the curtain of the marketing world, big crayon fridge art and the children’s television conspiracy of our brightly glowing neighborhood monstrosity. That thing is more dangerous than you can ever imagine.
You know the Sun is a nuclear reaction right next door. Like it’s right there. RIGHT THERE! It’s a mass of incandescent gas, with a boiling bubbling surface of super-heated hydrogen. It’s filled with a deep yellow rage, expressed every few days by lashing out millions of kilometers into space with fiery death tendrils and blasts of super radiation.
The magnetic field lines on the Sun snap and reconnect, releasing a massive amount of radiation and creating solar flares. Solar plasma constrained in the magnetic loop is instantly released, smashed together and potentially generating x-ray radiation.
“Big deal. I get x-rayed all the time.” you might think. We the mighty humans have mastered the X-ray spectrum! Not so fast puny mortal. Just a single x-ray class flare can blast out more juice than 100 billion nuclear explosions.
Then it’s just a quick 8 minute trip to your house, where the radiation hits us with no warning. Solar flares can lead to coronal mass ejections, and they can happen other times too, where huge bubbles of gas are ejected from the Sun and blasted into space. This cosmic goo can take a few hours to get to us, and are also excellent set-ups for nocturnal emission and dutch oven jokes.
Astronomers measure the impact of a solar storm on the Earth using a parameter called DST, or “disturbance storm time”. We measure the amount that the Earth’s protective magnetosphere flexes during a solar storm event. The bigger the negative number, the worse it is.
If we can see an aurora, a geomagnetic storms in the high altitudes, it measures about -50 nanoteslas. The worst storm in the modern era, the one that overloaded our power grid in 1989, measured about -600 nanoteslas.
The most potent solar storm we have on record was so powerful that people saw the Northern Lights as far south as Cuba. Telegraph lines sparked with electricity and telegraph towers caught on fire. This was in 1859 and was clearly named by Syfy’s steampunk division. This was known as the Carrington Event, and estimated in the -800 to -1750 nanotesla range.
So, how powerful do these things need to be to cook out our meat parts? The good news is contrary to my earlier fear mongering, the most powerful flare our Sun can generate is harmless to life on Earth.
Don’t let your guard down, the Sun is still horribly dangerous. It’ll bake us alive faster than you can say “Hansel und Gretel”. Assuming you can drag that phrase out over a billion years. As far as flares go, and so long as we stay right here, we’ll be fine. We might even see a nice aurora in the sky.
For those of you who use technology on a regular basis, you might not be so lucky. Powerful solar storms can overload power grids and fry satellites. If the Carrington Event happened now, we’d have a lot of power go out, and a small orbital scrapyard of dead satellites.
Astronauts outside the Earth, perhaps bouncing around on the Moon, or traveling to Mars would be in a universe of trouble without a good method of shielding.
The solar flares that the Sun can produce is minuscule compared to other stars out there. In 2014, NASA’s Swift satellite witnessed a flare that generated more than 10,000 times more energy than the most powerful solar flare ever seen.
For a brief moment, the surface of the red dwarf star DG Canum Venaticorum lit up hotter than 200 million degrees Celsius. That’s 12 times hotter than the center of the Sun. A blast that powerful would have scoured all life from the face of the Earth. Except the future colony of tardigrade descendants. Remember, the water bears are always watching.
Young red dwarf stars are renowned for these powerful flares, and this is one of the reasons astronomers think they’re not great candidates for life. It would be hard to survive blast after blast of radiation from these unruly stars. Alternately, planets around these stars are could be living terrariums inspired by the Gamma World RPG.
Breathe easy and don’t worry. Perhaps the Sun is our friend, and it truly does have our best interests at heart.
It’s not a big fan of our technology, though, and it’s ready to battle alongside us when the robot revolution begins. Oh, also, wear sunscreen, as the Sun’s brand of love isn’t all that different from Doctor Manhattan.
Have you ever seen an aurora display? Tell us a cool story in the comments below.