After Northern Lights appeared as far south as Colorado, Live Science discusses how "cannibal" coronal mass ejections (CME) are formed and what impact they have on Earth.
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00:00There are some beautiful auroras happening in the northwest of America right now.
00:04Yeah, so like NOAA scientists have given this a really, really simple explanation,
00:09and it's called a cannibal coronal mass ejection.
00:14That's the thing that's causing all of these auroras going on right now.
00:19Cannibal corona mass ejection.
00:22Yeah.
00:22That sounds a little terrifying.
00:24I mean, it's kind of funny, right?
00:25Because just as soon as we get over one kind of corona, we get hit by another.
00:28But this one, a cannibal coronal mass ejection, if I break that down for you,
00:34it's caused by sunspots.
00:36So there's a sunspot on the sun called AR2975 right now.
00:41And what it's been doing over the last, say, few days is producing up to 17 solar eruptions,
00:48two of which have headed straight towards us.
00:52Now, one of them was traveling faster than the other.
00:55It was the one that came just after the first one that was emitted.
01:01Now, when that second coronal mass ejection caught up with the first, it cannibalized it.
01:09It swept it all up into this one big wave of these charged particles,
01:14and then they all swept towards the Earth.
01:16And then when they hit it, they caused a geomagnetic storm.
01:21Where they come from in how sunspots are created is magnetic fields are created on the sun.
01:26The sun is just a giant ball of plasma.
01:29So there's loads of charged particles eddying and moving around inside the sun, across the
01:34sun's surface.
01:35Now, when you have charged particles moving, you're going to induce some magnetism there.
01:40But because magnetic field lines can't cross, and you've got all these moving particles,
01:44like this giant traffic jam of particles moving everywhere,
01:47you'll inevitably get these field lines bunched up next to each other.
01:50They'll form into these tight knots that can't escape anywhere else.
01:54And eventually, they will have to snap and release energy.
01:58Now, they release energy either in the form of a solar flare, like a bright flare of radiation,
02:03or they'll release energy in the form of like chucking out some of that plasma from the sun.
02:07What's the difference between solar flares and coronal mass ejections?
02:11So solar flares is just the bright flash that you'll see of radiation
02:16from that field line snapping that energy release.
02:19A coronal mass ejection is some of the sun's plasma soup actually being burped out of the sun.
02:26I love that phrase, plasma soup.
02:28Yeah, tasty plasma soup.
02:31I mean, pretty, but I mean, a little terrifying, right?
02:36I mean, does it affect Earth?
02:40So it does.
02:41But not in like a...
02:44So not in an always really terrible way.
02:47Most of the time, the Earth has a pretty strong magnetic field,
02:51which is really, really good news for us,
02:53because it protects us from all of these like highly energized particles
02:57that the sun has just spewed out at us.
02:59In this case, at like speeds of like 2 million miles per hour,
03:02which is just, I guess, 33 times less than the speed of light.
03:06Pretty quick.
03:07So what the Earth's magnetic field will do is it will absorb all of these particles.
03:14The energy will go into stretching out the magnetic field in space.
03:18So it's like it's kind of bunched out towards the...
03:21It gives it a long tail.
03:24And then most of those particles will gather kind of towards the poles
03:29where they will like go downwards and then energize some of the molecules in the atmosphere.
03:36And when these molecules in the atmosphere then give out light
03:41in order to kind of go down to a lower energy level,
03:44that's why we see the aurora.
03:46Now, because there's so many of these like particles coming in,
03:50you're getting auroras much lower down along the northern hemisphere
03:54than you would normally expect to see.
03:57That's a pretty...
03:59That's a nice effect there.
04:01And I know that people had already taken video from it.
04:06This is from Manitoba in Canada.
04:11Beautiful.
04:11Just absolutely beautiful.
04:13Yeah, yeah, yeah.
04:14And like I think also you could see the aurora in the U.S.
04:17certainly like as far south as Pennsylvania, Iowa and Oregon over the last few days as well.
04:23Oh, right.
04:24On spaceweather.com that you guys were sharing information from,
04:29they showed some pictures.
04:30Purple.
04:31I mean, purple.
04:33What an aura that Earth is giving off of this aurora.
04:37And when you mentioned poles,
04:41I'm like, that's why they're always up there towards the poles.
04:44We got to get closer to some poles, Ben.
04:46Yeah, yeah.
04:47But so, okay.
04:48So that's the good.
04:51How about damage?
04:53Okay, yes.
04:54So damage.
04:57So they can cause damage.
04:59So one of the most recent kind of power outages that was caused by a storm of this type
05:06was the 1989 Quebec power cut, which was caused by a geomagnetic storm.
05:11Now, most of the time,
05:13especially when it comes to people who provide like power lines and stuff,
05:16a lot of them have shielded like their power cables and things like that
05:20with a kind of Faraday cage, basically, which diverts the energy.
05:25Or they also have like other techniques that allow them to kind of siphon off excess energy
05:30that might be given to power lines by storms like this.
05:33But like that hasn't always been the case.
05:35Like, especially back in 1859,
05:38there was a really big event called the Great Carrington event,
05:41which was the largest sort of solar storm in modern human history.
05:45I'm sure there have been solar storms just as large throughout our past.
05:50But like before that point, we weren't really documenting it.
05:53We didn't have many electronics around, so we didn't really care.
05:57But in this case, the Great Carrington event fried
06:01most of the telegram systems in the US and in Europe that had been developed at the time.
06:06And it also led to auroras that could be seen around like as far south as the Caribbean.
06:13And like there were people waking up at night,
06:16thinking that it was daytime in the Caribbean
06:20because of these enormous auroras from this event.
06:23I mean, we're freaked out about it now when we see things like that.
06:26We know more, but I can't even imagine, you know, over 100 years ago.
06:30Yeah, exactly.
06:32In terms of more modern sort of phenomena that have caused more modern damage,
06:37other than the Quebec event,
06:39recently, actually, there was another geomagnetic storm
06:42that caused the downing of 40 of SpaceX's Starlink satellites.
06:48That was one thing that happened.
06:50And on top of that as well,
06:52there's a potential risk that the internet in general,
06:57especially in the United States, could be cut out by a geomagnetic storm
07:02because a lot of these cables run underwater
07:05through latitudes that would be affected by it.
07:09And you would have a geomagnetic storm.
07:12They're not shielded.
07:13So they would basically be probably quite severely affected by this.
07:16But as is the case with a lot of things and how they're done with legislation,
07:22it's like earthquakes.
07:22It doesn't often get legislated for until the worst has already happened.
07:26Yeah, that's a shame.
07:27I mean, I really like the internet.
07:29I really, I like to keep it around.
07:31This is how we get to communicate, right?
07:36But you're saying that we have protections now.
07:39So I think most power companies have already built in protections
07:44into their grids for these kind of things.
07:46It's just, yeah, you're not going to be getting any,
07:49I guess, coronal mass ejection memes in the middle of a coronal mass ejection.
07:53You have to wait a few weeks for them to fix the underwater cables.
07:57Yeah.
07:57And luckily, Earth, we have this nice electromagnetic shield, right?
08:02Already built in, otherwise we'd be goners.
08:05Yeah, it would fry us and it would also fry our atmosphere.
08:08Like a big reason why Mars doesn't have much of an atmosphere, for instance,
08:11is it doesn't really have a very active magnetic field.
08:14So all of the atmosphere, when it gets hit by this wave of hydrogen particles,
08:21like these protons, the atmosphere gets stripped away quite quickly.
08:25Poor Mars, poor Mars.
08:27Yeah.
08:28But that's why we're here, right?
08:30I mean, we are on Mars, but not yet.
08:33Not yet, not yet.
08:34Well, so is there a way to know when things like this will happen?
08:39I know we watch the sun, we have video of the sun.
08:42It seems more like after the fact.
08:46Yeah.
08:46So you get a bit of advanced warning.
08:49For instance, the Great Carrington Event is named after Richard Carrington,
08:52who spotted intense solar flares in the sky a few hours,
08:58maybe about 15 hours before the actual event hit.
09:02But the sun is quite a complex object.
09:05There's loads going on in those magnetic fields.
09:08It's still really, really hard for scientists to predict what's going on there.
09:11Yeah, if only, if only.
09:14Well, until the next major astronomical event.
09:18Thanks so much, Ben.