Visible light observations of a Coronal Mass Ejection (CME) acquired by the Wide Field Imager for Solar Probe (WISPR) telescopes
NASA’s Parker Solar Probe has been in studying the Sun for the last six years. In 2021 it was hit directly by a coronal mass ejection when it was a mere 10 million kilometres from the solar surface. Luckily it was gathering data and images enabling scientists to piece together an amazing video. The interactions between the solar wind and the coronal mass ejection were measured giving an unprecedented view of the solar corona.
A solar flare erupts on the Sun. Credit: NASA/GSFC/SDO
On December 14th, at 12:02 PM Eastern (09:02 AM Pacific), the Sun unleashed a massive solar flare. According to the Space Weather Prediction Center, part of the National Oceanic Atmospheric Administration (NOAA), this was the strongest flare of Solar Cycle 25, which began in 2019 and will continue until 2030. What’s more, scientists at the SWPC estimate that this may be one of the most powerful solar flares recorded since 1755 when extensive recording of solar sunspot activity began.
In the search for “potentially-habitable” extrasolar planets, one of the main things scientists look at is stellar activity. Whereas stars like our own, a G-type (G2V) yellow dwarf, are considered stable over time, other classes are variable and prone to flare-ups – particularly M-type red dwarf stars. Even if a star has multiple planets orbiting within its habitable zone (HZ), the tendency to periodically flare could render these planets completely uninhabitable.
According to a new study, stars like our own may not be as stable as previously thought. While observing EK Draconis, a G1.5V yellow dwarf located 110.71 light-years away, an international team of astronomers witnessed a massive coronal mass ejection that dwarfed anything we’ve ever seen in our Solar System. These observations suggest that these ejections can worsen over time, which could be a dire warning for life here on Earth.
If you’ve read enough of our articles, you know I’ve got an uneasy alliance with the Sun. Sure, it provides the energy we need for all life on Earth. But, it’s a great big ongoing thermonuclear reaction, and it’s right there! As soon as we get fusion, Sun, in like, 30 years or so, I tell you, we’ll be the ones laughing.
But to be honest, we still have so many questions about the Sun. For starters, we don’t fully understand the solar wind blasting out of the Sun. This constant wind of charged particles is constantly blowing out into space, but sometimes it’s stronger, and sometimes it’s weaker.
What are the factors that contribute to the solar wind? And as you know, these charged particles are not healthy for the human body, or for our precious electronics. In fact, the Sun occasionally releases enormous blasts that can damage our satellites and electrical grids.
How can we predict the intensity so that we can be better prepared for dangerous solar storms? Especially the Carrington-class events that might take down huge portions of our modern society.
Perhaps the biggest mystery with the Sun is the temperature of its corona. The surface of the Sun is hot, like 5,500 degrees Celsius. But if you rise up into the atmosphere of the Sun, into its corona, the temperature jumps beyond a million degrees.
The list of mysteries is long. And to start understanding what’s going on, we’ll need to get much much closer to the Sun.
Good news, NASA has a new mission in the works to do just that.
The Parker Solar Probe logo. Credit: NASA/JHUAPL
The mission is called the Parker Solar Probe. Actually, last week, it was called the Solar Probe Plus, but then NASA renamed it, and that reminded me to do a video on it.
It’s pretty normal for NASA to rename their spacecraft, usually after a dead astronomer/space scientist, like Kepler, Chandra, etc. This time, though, they renamed it for a legendary solar astronomer Eugene Parker, who developed much of our modern thinking on the Sun’s solar wind. Parker just turned 90 and this is the first time NASA has named it after someone living.
Anyway, back to the spacecraft.
The mission is due to launch in early August 2018 on a Delta IV Heavy, so we’re still more than a year away at this point. When it does, it’ll carry the spacecraft on a very unusual trajectory through the inner Solar System.
The problem is that the Sun is actually a very difficult place to reach. In fact, it’s the hardest place to get to in the entire Solar System.
Remember that the Earth is traveling around the Sun at a velocity of 30 km/s. That’s almost three times the velocity it takes to get into orbit. That’s a lot of velocity.
In order to be able to get anywhere near the Sun, the probe needs to shed velocity. And in order to do this, it’s going to use gravitational slingshots with Venus. We’ve talked about gravitational slingshots in the past, and how you can use them to speed up a spacecraft, but you can actually do the reverse.
The Parker Solar Probe will fall down into Venus’ gravity well, and give orbital velocity to Venus. This will put it on a new trajectory which takes it closer to the Sun. It’ll do a total of 7 flybys in 7 years, each of which will tweak its trajectory and shed some of that orbital momentum.
Parker Solar Probe’s trajectory including Venus flybys. Credit: NASA/JHUAPL
You know, trying to explain orbital maneuvering is tough. I highly recommend that you try out Kerbal Space Program. I’ve learned more about orbital mechanics by playing that game for a few months than I have in almost 2 decades of space journalism. Go ahead, try to get to the Sun, I challenge you.
Anyway, with each Venus flyby, the Parker Solar Probe will get closer and closer to the Sun, well within the orbit of Mercury. Far closer than any spacecraft has ever gotten to the Sun. At its closest point, it’ll only be 5.9 million kilometers from the Sun. Just for comparison, the Earth orbits at an average distance of about 150 million kilometers. That’s close.
And over the course of its entire mission, the spacecraft is expected to make a total of 24 complete orbits of the Sun, analyzing that plasma ball from every angle.
The orbit is also highly elliptical, which means that it’s going really really fast at its closest point. Almost 725,000 km/h.
In order to withstand the intense temperatures of being this close to the Sun, NASA has engineered the Parker Solar Probe to shed heat. It’s equipped with an 11.5 cm-thick shield made of carbon-composite. For that short time it spends really close to the Sun, the spacecraft will keep the shield up, blocking that heat from reaching the rest of its instruments.
And it’s going to get hot. We’re talking about more than 1,300 degrees Celsius, which is about 475 times as much energy as a spacecraft receives here on Earth. In the outer Solar System, the problem is that there just isn’t enough energy to power solar panels. But where Parker is going, there’s just too much energy.
Now we’ve talked about the engineering difficulties of getting a spacecraft this close to the Sun, let’s talk about the science.
Coronal holes are regions in the sun’s atmosphere or corona where solar plasma can stream directly into space. Often a hole will a couple rotations, inciting repeat auroras approximately every 4 weeks. Credit: NASA
The biggest question astronomers are looking to solve is, how does the corona get so hot. The surface is 5,500 Celsius. As you get farther away from the Sun, you’d expect the temperature to go down. And it certainly does once you get as far as the orbit of the Earth.
But the Sun’s corona, or its outer atmosphere, extends millions of kilometers into space. You can see it during a solar eclipse as this faint glow around the Sun. Instead of dropping, the temperature rises to more than a million degrees.
What could be causing this? There are a couple of ideas. Plasma waves pushed off the Sun could bunch up and release their heat into the corona. You could also get the crisscrossing of magnetic field lines that create mini-flares within the corona, heating it up.
The second great mystery is the solar wind, the stream of charged protons and electrons coming from the Sun. Instead of a constant blowing wind, it can go faster or slower. And when the speed changes, the contents of the wind change too.
There’s the slow wind, that goes a mere 1.1 million km/h and seems to emanate from the Sun’s equatorial regions. And then the fast wind, which seems to be coming out of coronal holes, cooler parts in the Sun’s corona, and can be going at 2.7 million km/h.
Why does the solar wind speed change? Why does its consistency change?
Parker Solar Probe’s instruments. Credit: NASA/JHUAPL
The Parker Solar Probe is equipped with four major instruments, each of which will gather data from the Sun and its environment.
The FIELDS experiment will measure the electric and magnetic fields and waves around the Sun. We know that much of the Sun’s behavior is driven by the complex interaction between charged plasma in the Sun. In fact, many physicists agree that magnetohydrodynamics is easily one of the most complicated fields you can get into.
Integrated Science Investigation of the Sun, or ISOIS (which I suspect needs a renaming) will measure the charged particles streaming off the Sun, during regular solar activity and during dangerous solar storms. Can we get any warning before these events occur, giving astronauts more time to protect themselves?
Wide-field Imager for Solar PRobe or WISPR is its telescope and camera. It’s going to be taking close up, high resolution images of the Sun and its corona that will blow our collective minds… I hope. I mean, if it’s just a bunch of interesting data and no pretty pictures, it’s going to be hard to make cool videos showcasing the results of the mission. You hear me NASA, we want pictures and videos. And science, sure.
And then the Solar Wind Electrons Alphas and Protons Investigation, or SWEAP, will measure type, velocity, temperature and density of particles around the Sun, to help us understand the environment around it.
One interesting side note, the spacecraft will be carrying a tiny chip on board with photos of Eugene Parker and a copy of his original 1958 paper explaining the Sun’s solar wind.
The Parker Solar Probe orbiting the Sun. Credit: NASA/JHUAPL
I know we’re still more than a year away from liftoff, and several years away before the science data starts pouring in. But you’ll be hearing more and more about this mission shortly, and I’m pretty excited about what it’s going to accomplish. So stay tuned, and once the science comes in, I’m sure you’ll hear plenty more about it.
Isn’t modern society great? With all this technology surrounding us in all directions. It’s like a cocoon of sweet, fluffy silicon. There are chips in my fitness tracker, my bluetooth headset, mobile phone, car keys and that’s just on my body.
At all times in the Cain household, there dozens of internet devices connected to my wifi router. I’m not sure how we got to the point, but there’s one thing I know for sure, more is better. If I could use two smartphones at the same time, I totally would.
And I’m sure you agree, that without all this technology, life would be a pale shadow of its current glory. Without these devices, we’d have to actually interact with each other. Maybe enjoy the beauty of nature, or something boring like that.
It turns out, that terrible burning orb in the sky, the Sun, is fully willing and capable of bricking our precious technology. It’s done so in the past, and it’s likely to take a swipe at us in the future.
I’m talking about solar storms, of course, tremendous blasts of particles and radiation from the Sun which can interact with the Earth’s magnetosphere and overwhelm anything with a wire.
Credit: NASA
In fact, we got a sneak preview of this back in 1859, when a massive solar storm engulfed the Earth and ruined our old timey technology. It was known as the Carrington Event.
Follow your imagination back to Thursday, September 1st, 1859. This was squarely in the middle of the Victorian age.
And not the awesome, fictional Steampunk Victorian age where spectacled gentleman and ladies of adventure plied the skies in their steam-powered brass dirigibles.
No, it was the regular crappy Victorian age of cholera and child labor. Technology was making huge leaps and bounds, however, and the first telegraph lines and electrical grids were getting laid down.
Imagine a really primitive version of today’s electrical grid and internet.
On that fateful morning, the British astronomer Richard Carrington turned his solar telescope to the Sun, and was amazed at the huge sunspot complex staring back at him. So impressed that he drew this picture of it.
Richard Carrington’s sketch of the sunspots seen just before the 1859 Carrington event.
While he was observing the sunspot, Carrington noticed it flash brightly, right in his telescope, becoming a large kidney-shaped bright white flare.
Carrington realized he was seeing unprecedented activity on the surface of the Sun. Within a minute, the activity died down and faded away.
And then about 5 minutes later. Aurora activity erupted across the entire planet. We’re not talking about those rare Northern Lights enjoyed by the Alaskans, Canadians and Northern Europeans in the audience. We’re talking about everyone, everywhere on Earth. Even in the tropics.
In fact, the brilliant auroras were so bright you could read a book to them.
The beautiful night time auroras was just one effect from the monster solar flare. The other impact was that telegraph lines and electrical grids were overwhelmed by the electricity pushed through their wires. Operators got electrical shocks from their telegraph machines, and the telegraph paper lit on fire.
What happened? The most powerful solar flare ever observed is what happened.
In this image, the Solar Dynamics Observatory (SDO) captured an X1.2 class solar flare, peaking on May 15, 2013. Credit: NASA/SDO
A solar flare occurs because the Sun’s magnetic field lines can get tangled up in the solar atmosphere. In a moment, the magnetic fields reorganize themselves, and a huge wave of particles and radiation is released.
Flares happen in three stages. First, you get the precursor stage, with a blast of soft X-ray radiation. This is followed by the impulsive stage, where protons and electrons are accelerated off the surface of the Sun. And finally, the decay stage, with another burp of X-rays as the flare dies down.
These stages can happen in just a few seconds or drag out over an hour.
Remember those particles hurled off into space? They take several hours or a few days to reach Earth and interact with our planet’s protective magnetosphere, and then we get to see beautiful auroras in the sky.
This geomagnetic storm causes the Earth’s magnetosphere to jiggle around, which drives charges through wires back and forth, burning out circuits, killing satellites, overloading electrical grids.
Back in 1859, this wasn’t a huge deal, when our quaint technology hadn’t progressed beyond the occasional telegraph tower.
Today, our entire civilization depends on wires. There are wires in the hundreds of satellites flying overhead that we depend on for communications and navigation. Our homes and businesses are connected by an enormous electrical grid. Airplanes, cars, smartphones, this camera I’m using.
Credit: Wikimedia Commons.
Everything is electronic, or controlled by electronics.
Think it can’t happen? We got a sneak preview back in March, 1989 when a much smaller geomagnetic storm crashed into the Earth. People as far south as Florida and Cuba could see auroras in the sky, while North America’s entire interconnected electrical grid groaned under the strain.
The Canadian province of Quebec’s electrical grid wasn’t able to handle the load and went entirely offline. For 12 hours, in the freezing Quebec winter, almost the entire province was without power. I’m telling you, that place gets cold, so this was really bad timing.
Satellites went offline, including NASA’s TDRS-1 communication satellite, which suffered 250 separate glitches during the storm.
And on July 23, 2012, a Carrington-class solar superstorm blasted off the Sun, and off into space. Fortunately, it missed the Earth, and we were spared the mayhem.
If a solar storm of that magnitude did strike the Earth, the cleanup might cost $2 trillion, according to a study by the National Academy of Sciences.
The July 23, 2012 CME would have caused a Carrington-like event had it hit Earth. Thankfully for us and our technology, it missed. Credit: NASA’s Goddard Space Flight Center
It’s been 160 years since the Carrington Event, and according to ice core samples, this was the most powerful solar flare over the last 500 years or so. Solar astronomers estimate solar storms like this happen twice a millennium, which means we’re not likely to experience another one in our lifetimes.
But if we do, it’ll cause worldwide destruction of technology and anyone reliant on it. You might want to have a contingency plan with some topic starters when you can’t access the internet for a few days. Locate nearby interesting nature spots to explore and enjoy while you wait for our technological civilization to be rebuilt.
Have you ever seen an aurora in your lifetime? Give me the details of your experience in the comments.
Hubble Space Telescope view of a plume high in the martian atmosphere seen in May 1997. Credit: NASA/ESA
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 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
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.
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.
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 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, 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.
Technicians work on NASA’s 20-foot-tall Magnetospheric Multiscale (MMS) mated quartet of stacked observatories in the cleanroom at NASA's Goddard Space Flight Center in Greenbelt, Md., on May 12, 2014. Credit: Ken Kremer- kenkremer.com
NASA’s first mission dedicated to study the process in nature known as magnetic reconnection undergoing final preparation for launch from Cape Canaveral, Florida in just under two weeks time.
The Magnetospheric Multiscale (MMS) mission is comprised of a quartet of identically instrumented observatories aimed at providing the first three-dimensional views of a fundamental process in nature known as magnetic reconnection.
Magnetic reconnection is the process whereby magnetic fields around Earth connect and disconnect while explosively releasing vast amounts of energy. It occurs throughout the universe.
“Magnetic reconnection is one of the most important drivers of space weather events,” said Jeff Newmark, interim director of the Heliophysics Division at NASA Headquarters in Washington.
“Eruptive solar flares, coronal mass ejections, and geomagnetic storms all involve the release, through reconnection, of energy stored in magnetic fields. Space weather events can affect modern technological systems such as communications networks, GPS navigation, and electrical power grids.”
The four MMS have been stacked on top of one another like pancakes, encapsulated in the payload fairing, transported to the launch pad, hoisted and mated to the top of the 195-foot-tall rocket.
NASA’s Magnetospheric Multiscale (MMS) observatories are shown here in the clean room being processed for a March 12, 2015 launch from Space Launch Complex 41 on Cape Canaveral Air Force Station, Florida. Credit: NASA/Ben Smegelsky
The nighttime launch of MMS on a United Launch Alliance Atlas V rocket should put on a spectacular sky show for local spectators along the Florida space coast as well as more distant located arcing out in all directions.
Liftoff is slated for 10:44 p.m. EDT Thursday March 12 from Space Launch Complex 41 on Cape Canaveral Air Force Station, Florida.
The launch window extends for 30 minutes.
Artist rendition of the four MMS spacecraft in orbit in Earth’s magnetic field. Credit: NASA
After a six month check out phase the probes will start science operation in September.
Unlike previous missions to observe the evidence of magnetic reconnection events, MMS will have sufficient resolution to measure the characteristics of ongoing reconnection events as they occur.
The four probes were built in-house by NASA at the agency’s Goddard Space Flight Center in Greenbelt, Maryland where is visited them during an inspection tour by NASA Administrator Charles Bolden.
I asked Bolden to explain the goals of MMS during a one-on-one interview.
“MMS will help us study the phenomena known as magnetic reconnection and help us understand how energy from the sun – magnetic and otherwise – affects our own life here on Earth,” Bolden told Universe Today.
“MMS will study what effects that process … and how the magnetosphere protects Earth.”
MMS measurements should lead to significant improvements in models for yielding better predictions of space weather and thereby the resulting impacts for life here on Earth as well as for humans aboard the ISS and robotic satellite explorers in orbit and the heavens beyond.
NASA Administrator Charles Bolden poses with the agency’s Magnetospheric Multiscale (MMS) spacecraft, mission personnel, Goddard Center Director Chris Scolese and NASA Associate Administrator John Grunsfeld, during visit to the cleanroom at NASA’s Goddard Space Flight Center in Greenbelt, Md., on May 12, 2014. Credit: Ken Kremer- kenkremer.com
The best place to study magnetic reconnection is ‘in situ’ in Earth’s magnetosphere. This will lead to better predictions of space weather phenomena.
“This is the perfect time for this mission,” said Jim Burch, principal investigator of the MMS instrument suite science team at Southwest Research Institute (SwRI) in San Antonio, Texas.
“MMS is a crucial next step in advancing the science of magnetic reconnection. Studying magnetic reconnection near Earth will unlock the ability to understand how this process works throughout the entire universe.”
Magnetic reconnection is also believed to help trigger the spectacular aurora known as the Northern or Southern lights.
MMS is a Solar Terrestrial Probes Program, or STP, mission within NASA’s Heliophysics Division.
Watch for Ken’s ongoing MMS coverage and he’ll be onsite at the Kennedy Space Center in the days leading up to the launch on March 12.
Stay tuned here for Ken’s continuing MMS, Earth and planetary science and human spaceflight news.
Ken Kremer
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Learn more about MMS, Mars rovers, Orion, SpaceX, Antares, NASA missions and more at Ken’s upcoming outreach events:
Mar 6: “MMS Update, Future of NASA Human Spaceflight, Curiosity on Mars,” Delaware Valley Astronomers Assoc (DVAA), Radnor, PA, 7 PM.
Mar 10-12: “MMS, Orion, SpaceX, Antares, Curiosity Explores Mars,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Panel of negative images showing the tail of Comet Lovejoy disconnecting. Credit: Hisayoshi Kato
Maybe you’ve seen Comet Q2 Lovejoy. It’s a big fuzzy ball in binoculars low in the southern sky in the little constellation Lepus the Hare. That’s the comet’s coma or temporary atmosphere of dust and gas that forms when ice vaporizes in sunlight from the nucleus. Until recently a faint 3° ion or gas tail trailed in the coma’s wake, but on and around December 23rd it snapped off and was ferried away by the solar wind. Just as quickly, Lovejoy re-grew a new ion tail but can’t seem to hold onto that one either. Like a feather in the wind, it’s in the process of being whisked away today.
Magnetic field lines bound up in the sun’s wind pile up and drape around a comet’s nucleus to shape the blue ion tail. Notice the oppositely-directed fields on the comet’s backside. The top set points away from the comet; the bottom set toward. In strong wind gusts, the two can be squeezed together and reconnect, releasing energy that snaps off a comet’s tail. Credit: Tufts University.
Easy come, easy go. Comets usually have two tails, one of dust particles that reflect sunlight and another of ionized gases that fluoresce in Sun’s ultraviolet radiation. Ion tails form when cometary gases, primarily carbon monoxide, are ionized by solar radiation and lose an electron to become positively charged. Once “electrified”, they’re susceptible to magnetic fields embedded in the high-speed stream of charged particles flowing from the Sun called the solar wind. Magnetic field lines embedded in the wind drape around the comet and draw the ions into a long, skinny tail directly opposite the Sun.
Part of Comet Lovejoy Q2’s ion tail (left) cuts the cord and floats away from the comet as photographed on December 23, 2014. Carbon monoxide in the tail fluoresces blue in ultraviolet sunlight. Credit: Chris Schur
Disconnection events happen when fluctuations in the solar wind cause oppositely directed magnetic fields to reconnect in explosive fashion and release energy that severs the tail. Set free, it drifts away from the comet and dissipates. In active comets, the nucleus continues to produce gases, which in turn are ionized by the Sun and drawn out into a replacement appendage. In one of those delightful coincidences, comets and geckos both share the ability to re-grow a lost tail.
Comet Encke tail disconnection April 20, 2007 as seen by STEREO
Comet Halley experienced two ion tail disconnection events in 1986, but one of the most dramatic was recorded by NASA’s STEREO spacecraft on April 20, 2007. A powerful coronal mass ejection (CME) blew by comet 2P/Encke that spring day wreaking havoc with its tail. Magnetic field lines from the plasma blast reconnected with opposite polarity magnetic fields draped around the comet much like when the north and south poles of two magnets snap together. The result? A burst of energy that sent the tail flying.
Diagram showing how a CME slammed into Comet Encke (B) and snapped off its tail. Soon enough, the comet grew a new one (D). Credit: NASA
Comet Lovejoy may have also crossed a sector boundary where the magnetic field carried across the Solar System by Sun’s constant breeze changed direction from south to north or north to south, opposite the magnetic domain the comet was immersed in before the crossing. Whether solar wind flutters, coronal mass ejections or sector boundary crossings, more tail budding likely lies in Lovejoy’s future. Like the chard in your garden that continues to sprout after repeated snipping, the comet seems poised to spring new tails on demand.
Comet Lovejoy picks up speed in late December as it travels from southern Lepus into Eridanus. Its position shown nightly at 10 p.m. (CST). On Sunday night December 28th it passes very close to the bright globular cluster M79. Stars shown to magnitude +8.0. Source: Chris Marriott’s SkyMap software
If you haven’t seen the comet, it’s now glowing at magnitude +5.5 and faintly visible to the naked eye from a dark sky site. Without an obvious dust tail and sporting a faint ion tail(s), the comet’s basically a giant coma, a fuzzy glowing ball easily visible in a pair of binoculars or small telescope.
A second tail disconnection event recorded on December 26, 2014 by John Nassr from his observatory in Baguio, Philippines. The frame is 3° wide. Credit: John Nassr
In a very real sense, Comet Lovejoy experienced a space weather event much like what happens when a CME compresses Earth’s magnetic field causing field lines of opposite polarity to reconnect on the back or nightside of the planet. The energy released sends millions of electrons and protons cascading down into our upper atmosphere where they stimulate molecules of oxygen and nitrogen to glow and produce the aurora. One wonders whether comets might even experience their own brief auroral displays.
Excellent visualization showing how magnetic fields line on Earth’s nightside reconnect to create the rain of electrons that cause the aurora borealis. Notice the similarity to comet tail loss.
Solar prominences and filaments on the Sun on September 18, 2014, as seen with a hydrogen alpha filter. Credit and copyright: John Chumack/Galactic Images.
This is a question we are often asked: what is the difference between a coronal mass ejection (CME) and a solar flare? We discussed it in a recent astrophoto post, but today NASA put out a video with amazing graphics that explains it — and visualizes it — extremely well.
“CMEs and solar flares are both explosions that occur on the Sun,” the folks at NASA’s Goddard Spaceflight Center’s Scientific Visualization Studio explain. “Sometimes they occur together, but they are not the same thing.”
CMEs are giant clouds of particles from the Sun hurled out into space, while flares are flashes of light — occurring in various wavelengths — on the Sun.
A "triple X" on June 10-11, 2014 with three flares from AR2087 (NASA/SDO/GSFC)
Remember yesterday when we mentioned two X-class flares erupting from the Sun within the space of about an hour? We probably should have waited a bit and gone for the trifecta: this morning the same active region flared yet again, making it three high-powered flares within a single 24-hour period.
(And to think this active region has only just come around the corner!)
On June 10, 2014, AR2087 announced its arrival around the southwestern limb of the Sun with an X2.2 flare at 11:41 UT (7:41 a.m. EDT). Then, just over an hour later, another eruption: an X1.5 flare at 12:55 UT. This got pretty much everyone’s attention… here comes 2087!
Perhaps figuring third time’s a charm, the active region blazed with a third flare this morning at 9:05 UT (5:05 a.m. EDT). “Only” an X1-class, it was the weakest of the three but AR2087 still has plenty of time for more as it makes its way around the Sun’s face — all the while aiming more and more our way, too.
Here’s a video of SDO observations showing the two June 10 flares:
X-class flares are the strongest in the letter-classification of solar flares, which send blasts of electromagnetic energy out into the Solar System. While these most recent three are low on the X-scale, they may result in increased auroral activity — especially since it appears that the first two were followed by a pair of CMEs that “cannibalized” each other on their way out. The resulting merged cloud of charged particles is expected to nick Earth’s magnetic field on Friday, June 13. (Source: Spaceweather.com)
No CME has been observed from the June 11 flare, but again: AR2087 hasn’t left the stage yet. Stay tuned!
Source: NASA. Learn more about how solar flares impact us on Earth here.
