AURORAS IN THE USA: A coronal mass ejection (CME) hit Earth on Oct. 24th at approximately 1800 UT (2:00 pm EDT). The impact strongly compressed Earth's magnetic field, directly exposing geosynchronous satellites to solar wind plasma, and sparked an intense geomagnetic storm. As night fell over North America, auroras spilled across the Canadian border into the contiguous United States. A US Department of Defense satellite photographed the crossing:
"This shows the auroras on Oct. 25th at 0140 GMT," says Paul McCrone of the Fleet Numerical Meteorology and Oceanography Center in Monterey, California. He created the image using visual and infrared data from the Defense Meteorological Satellite Program's F18 polar orbiter. DMSP satellites carry low light cameras for nightime monitoring of moonlit clouds, city lights and auroras. Some of the auroras recorded by the F18 on Oct. 25th were as bright as the city lights underneath.
This "big picture" from orbit makes sense of what happened next. The bright band swept south and, before the night was over, auroras were sighted in more than thirty US states: Alabama, Wisconsin, New Mexico, Tennessee, Missouri, Illinois, Nebraska, Kentucky, North Carolina, Indiana, Oklahoma, Kansas, Iowa, Maryland, New York, Montana, Ohio, Colorado, Pennsylvania, Washington, Virginia, Texas, Arizona, Minnesota, Maine, Michigan, Montana, Oregon, Arkansas and California.
Many observers, especially in the deep south, commented on the pure red color of the lights they saw. These rare all-red auroras sometimes appear at low latitudes during intense geomagnetic storms. They occur some 300 to 500 km above Earth's surface and are not yet fully understood.
October 25, 2011 2:33 PM
Unforgettable Northern Lights display recordedThe aurora display, also known as the northern lights, was touched off by a wave charged particles unleashed by a massive sun storm on Saturday, which took two days to reach Earth, according to the Space Weather Prediction Center operated by the National Weather Service and NOAA.
"These were the most vibrant I've ever seen," Canadian skywatcher Colin Chatfield of Saskatoon, Saskatchewan told SPACE.com in an email. "I was also able to see red with the naked eye, which I've never seen before either. Simply put, they were amazing."
(Credit: Colin Chatfield)
Photographer Shawn Malone in Marquette, Mich., expected a good aurora light show, but was still surprised by the sheer brilliance of Monday night's northern light show.
"[I] had taken a few pics, went back to the car to change lenses, and when I looked up the sky was on fire," Malone said. "To the north there was this huge curtain that sent beams overhead to a corona in which I had to turn to the south to photograph. That's when I noticed the reds and pinks starting to happen. From there the lights were every which direction. It was hands down the best northern lights I've seen since the great storm of November 2004."
(Credit: Shawn Malone)
"Couple that with the fact that large parts of the U.S. had very clear skies, and you've got some beautiful sightings of the aurora across the northern tier of the U.S.," Space Weather Prediction Center officials wrote in an update. Unfortunately for sky watchers, the geomagnetic storm appears to be in decline and no further significant space weather is expected at this time."
(Credit: Samuel Hartman)
Traditionally, only skywatchers in high-latitude locations can see aurora displays, but during strong solar weather events, they can be visible to observers at lower latitudes. A dark, clear sky away from city lights is vital to spot the displays.
Green auroras, caused by the ionization of atomic oxygen in the atmosphere, are the most common northern lights seen. Red aurora displays are rarer, and are caused by the ionization of molecular oxygen and nitrogen.
"I was surprised to find the auroras out so brightly," said Samuel Hartman, a skywatcher in State College, Pa., who sent photos to SPACE.com. "It was originally supposed to be cloudy all night, but the clouds cleared and the aurora was glowing bright. It made for an excellent show."
(Credit: Jeff Berkes)
"I ran outside and jumped in my car leaving the tripod inside. I used the top of my Xterra and a sweatshirt to create a make-shift tripod," Berkes told SPACE.com in an email. "The auroras only last a few minutes. But hey it was awesome! Haven't seen them here since September 2001."
Monday night's auroras were seen as far south as Arkansas, where skywatcher and photographer Brian Emfinger caught the view from the city of Ozark.
"The auroras filled the sky in every direction - even to the south," Emfinger told the skywatching website Spaceweather.com, adding that it was the website's email alert that warned him of the stunning aurora show. "When I saw the alert, I ran outside and immediately saw red auroras. Within a few minutes the auroras went crazy! Unbelievable!"
(Credit: Tom Pruzenski)
In Hemlock, N.Y., first-time aurora photographer Tom Pruzenski expressed a similar sentiment.
"This outburst of red auroras happened around 9:30 p.m.," Pruzenski said. "My brother (and amateur astronomer) Chris Pruzenski noticed faint auroras two hours earlier, around 7:30 p.m. We waited and watched, and our patience paid off with this 5-10 minute display of red and green auroras."
Tom Dolaskie IV watched the northern lights dance over Lake Superior at Munising Bay in Michigan. The view, he said, was astounding and not one he will soon forget.
"Hands down the most amazing northern lights display that I have ever witnessed," Dolaskie said. "Frankly, a setting that a photograph simply cannot capture. My friends and I were lucky to have witnessed it."
Editor's note: If you snapped a great photo of Monday night's northern lights and would like to share the image and your comments with SPACE.com, please contact managing editor Tariq Malik at tmalik@space.com.
http://www.cbsnews.com/8301-205_162-20125354/unforgettable-northern-lights-display-recorded/
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