Gigantic Sunspot Unleashes Flare; Expect Aurorae Tonight!

Bad Astronomy
The entire universe in blog form
Jan. 8 2014 1:16 PM

Gigantic Sunspot Unleashes Flare; Expect Aurorae Tonight!

solar flare
The sunspot cluster AR1944 blasted out a moderately strong solar flare yesterday, and we may get aurorae tonight.

Photo by NASA/ESA/SDO/Helioviewer.org

Right now, the Sun is sporting a huge sunspot called AR1944. It’s grown in size over the past few days to a staggering 200,000 kilometers (125,000 miles) across. As I wrote the other day, sunspots are regions of intense magnetism, and these magnetic fields store huge energies. They can be unleashed in vast explosions called solar flares … and AR1944 popped off a good one on Jan. 7. The image above shows the Sun in ultraviolet by NASA’s Solar Dynamics Observatory, taken on Jan. 7 at 18:33 UTC, just after the flare exploded. The bright white patch? Yeah, that’s it.

The flare was a class X1, which is pretty strong. It also triggered a coronal mass ejection, an eruption of subatomic particles, toward the Earth. There’s no need to panic; these happen relatively often. This one was pretty fast, with a speed of about 2,000 kilometers per second—that’s 4.5 million miles per hour!

sun
I took this photo on Jan. 8 at about 17:00 UTC, and you can easily see AR1944. The biggest sunspot in the cluster is now 15 times the width of our entire planet.

Photo by Phil Plait

Advertisement

It’s expected to hit the Earth’s magnetic field sometime today or tonight. The Space Weather Prediction Center says it may interact strongly with our geomagnetic field, producing aurorae. I’ve seen some folks predicting even mid-latitudes may see the lights, so I urge folks to go out after dark and look north. Unfortunately the Moon is half-full and so the sky will be a bit bright. It sets just after midnight local time, so if you go out later your chances of seeing the aurora might be better. It looks like we’ll have clear skies here in Boulder, Colo., so I’ll be taking a peek. Aurorae may still be visible Thursday night as well.

I’ll note that this storm provoked the delay of an Orbital Sciences Corporation launch of their Antares rocket, scheduled to lift off today on a resupply mission to the International Space Station. The increased radiation levels could screw up the systems onboard, so they decided to postpone. Follow Orbital on Twitter for up-to-date info on that.

Once this thing hits us I’ll try to follow up, but your best bet is to check SpaceWeather.com and follow me on Twitter for the latest news; I’ll try to post updates there as I see them.

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death From the Skies!  

TODAY IN SLATE

The Slatest

Ben Bradlee Dead at 93

The legendary Washington Post editor presided over the paper’s Watergate coverage.

This Scene From All The President’s Men Captures Ben Bradlee’s Genius

Renée Zellweger’s New Face Is Too Real

Sleater-Kinney Was Once America’s Best Rock Band

Can it be again?

Whole Foods Is Desperate for Customers to Feel Warm and Fuzzy Again

The XX Factor

I’m 25. I Have $250.03.

My doctors want me to freeze my eggs.

The XX Factor
Oct. 20 2014 6:17 PM I’m 25. I Have $250.03. My doctors want me to freeze my eggs.
Technocracy

Forget Oculus Rift

This $25 cardboard box turns your phone into an incredibly fun virtual reality experience.

George Tiller’s Murderer Threatens Another Abortion Provider, Claims Free Speech

The Congressional Republican Digging Through Scientists’ Grant Proposals

  News & Politics
The World
Oct. 21 2014 3:13 PM Why Countries Make Human Rights Pledges They Have No Intention of Honoring
  Business
Moneybox
Oct. 21 2014 5:57 PM Soda and Fries Have Lost Their Charm for Both Consumers and Investors
  Life
The Vault
Oct. 21 2014 2:23 PM A Data-Packed Map of American Immigration in 1903
  Double X
The XX Factor
Oct. 21 2014 3:03 PM Renée Zellweger’s New Face Is Too Real
  Slate Plus
Behind the Scenes
Oct. 21 2014 1:02 PM Where Are Slate Plus Members From? This Weird Cartogram Explains. A weird-looking cartogram of Slate Plus memberships by state.
  Arts
Brow Beat
Oct. 21 2014 9:42 PM The All The President’s Men Scene That Perfectly Captured Ben Bradlee’s Genius
  Technology
Technology
Oct. 21 2014 5:38 PM Justified Paranoia Citizenfour offers a look into the mind of Edward Snowden.
  Health & Science
Climate Desk
Oct. 21 2014 11:53 AM Taking Research for Granted Texas Republican Lamar Smith continues his crusade against independence in science.
  Sports
Sports Nut
Oct. 20 2014 5:09 PM Keepaway, on Three. Ready—Break! On his record-breaking touchdown pass, Peyton Manning couldn’t even leave the celebration to chance.