NASA has captured video of a solar storm blowing over Earth for the first time ever. Better yet, they’ve shared it.
The agency was able to flip its STEREO solar imaging spacecraft to face the Earth and record the effects of bursts of solar wind known as coronal mass ejections. Using new data processing techniques, NASA tracked a singe CME all the way from the Sun until it engulfed Earth.
“The movie sent chills down my spine,” Craig DeForest of the Southwest Researcher Institute in Boulder, Colorado, said in a release. “It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live. I felt very small.”
NASA says the data helps clear up a 40-year mystery about the structure of CMEs, which are a major part of space weather. Made up of clouds of solar plasma that weigh billions of tons, CMEs are released in the same types explosions that cause solar flares. Their effects are similar, and can cause everything from auroras to radiation storms. As these types of extreme space weather can have such material impacts as power outages, the ability to forecast space storms is very important.
STEREO-A caught the event from more than 65 million miles from Earth. It is the first of two spacecraft launched in 2006 to monitor solar activity from long distance. Yet while the spacecraft can record the event, processing the data into something meaningful is incredibly difficult.
“Until quite recently, spacecraft could see CMEs only when they were still quite close to the sun,” Alysha Reinard of NOAA’s Space Weather Prediction Center said. “By calculating a CME’s speed during this brief period, we were able to estimate when it would reach Earth. After the first few hours, however, the CME would leave this field of view and after that we were ‘in the dark’ about its progress.”
As the CME cloud leaves the Sun, it disperses into space and become ever-fainter. As you might imagine, by the time the radiation crosses the 93 million miles to reach the Earth, it’s become unbelievably hard to measure. In fact, the event shown in the video actually occurred in 2008, and DeForest’s team spent the last three years figuring out how to isolate evidence of the CME all the way to Earth.
“The ability to track a cloud continuously from the Sun to Earth is a big improvement,” she said. “In the past, our very best predictions of CME arrival times had uncertainties of plus or minus 4 hours. The kind of movies we’ve seen today could significantly reduce the error bars.”
Thankfully, now that they’ve sorted out how to track a CME once, data recorded by the STEREO spacecraft should make predicting solar storms far easier and more accurate than they are today.
Video and screenshot via NASA/STEREO/Scott Wiessinger
