Latest THEMIS Stories

WASHINGTON, Dec. 15 /PRNewswire-USNewswire/ -- NASA landed on Mars, photographed distant worlds, added to the International Space Station, took part in a lunar science mission with India and made major progress toward returning astronauts to the moon as the agency celebrated its 50th birthday in 2008. Here on Earth, NASA researchers recorded the continued decline of Arctic sea ice, won awards for aviation breakthroughs, discovered the cause of storms that brighten the Northern Lights and...

During the time it takes you to read this article, something will happen high overhead that until recently many scientists didn't believe in. A magnetic portal will open, linking Earth to the sun 93 million miles away. Tons of high-energy particles may flow through the opening before it closes again, around the time you reach the end of the page."It's called a flux transfer event or 'FTE,'" says space physicist David Sibeck of the Goddard Space Flight Center. "Ten years ago I...

U.S. scientists working with NASA said they've uncovered the source of substorms in space that fuel the explosive energy behind the northern lights. Vassilis Angelopoulos, a professor at the University of California, Los Angeles and lead investigator of the NASA-funded mission known as THEMIS -- Time History of Events and Macroscale Interactions, said the energy comes from magnetic fields. Our data show clearly and for the first time that magnetic reconnection is the trigger, Angelopoulos...

MINNEAPOLIS, July 24 /PRNewswire-FirstCall/ -- Alliant Techsystems reported today that the constellation of five micro satellites it built for NASA's THEMIS (Time History of Events and Macroscale Interactions during Substorms) mission has successfully demonstrated how satellites can work together to collect data, which in this case, advances the scientific understanding of the Earth's atmosphere. The THEMIS mission determined the cause of the shimmering effect of the Aurora Borealis,...

Researchers using a fleet of five NASA satellites have discovered that explosions of magnetic energy a third of the way to the moon power substorms that cause sudden brightenings and rapid movements of the aurora borealis, called the Northern Lights.The culprit turns out to be magnetic reconnection, a common process that occurs throughout the universe when stressed magnetic field lines suddenly snap to a new shape, like a rubber band that's been stretched too far."We discovered what...

One of the most dynamic events in the interaction between the Sun and the Earth is a "˜substorm', an explosive reshaping of the Earth's outer magnetic field. To better understand substorms, scientists in Europe and North America are studying them from space using the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites launched by NASA in 2007 and from the ground using a network of all-sky cameras. In her talk on Tuesday 1 April at the RAS National...

What are the signs of spring? They are as familiar as a blooming Daffodil, a songbird at dawn, a surprising shaft of warmth from the afternoon sun.And, oh yes, don't forget the aurora borealis.Spring is aurora season. For reasons not fully understood by scientists, the weeks around the vernal equinox are prone to Northern Lights. Canadians walking their dogs after dinner, Scandinavians popping out to the sauna, Alaskan Huskies on the Iditarod trail"”all they have to do is look up and...

Imagine living on a planet where Northern Lights fill the heavens at all hours of the day. Around the clock, even in broad daylight, luminous curtains shimmer and ripple across the sky, mesmerizing anyone who bothers to look.News flash: Astronomers have discovered such a planet. Its name is Earth."Our own planet has auroras 24 hours a day," says Jim Spann of the Marshall Space Flight Center, "and we can see them even in broad daylight." The trick, he explains, is picking...

What are the signs of spring? They are as familiar as a blooming daffodil, a songbird at dawn, a surprising shaft of warmth from the afternoon sun. And, oh yes, don't forget the aurora borealis. Spring is aurora season. For reasons not fully understood by scientists, the weeks around the vernal equinox are prone to Northern Lights. Canadians walking their dogs after dinner, Scandinavians popping out to the sauna, Alaskan Huskies on the Iditarod trail -- all they have to do is look up and...

NASA's fleet of THEMIS spacecraft, launched less than 8 months ago, has made three important discoveries about spectacular eruptions of Northern Lights called "substorms" and the source of their power. The discoveries include giant magnetic ropes that connect Earth's upper atmosphere to the Sun and explosions in the outskirts of Earth's magnetic field."The mission is only beginning but THEMIS is already surprising us," says Vassilis Angelopoulos the mission's principal...