A ring of radiation previously unknown to science fleetingly surrounded Earth last year before being virtually annihilated by a powerful interplanetary shock wave, scientists say.
NASA’s twin Van Allen space probes, which are studying the Earth’s radiation belts, made the cosmic find. The surprising discovery — a new, albeit temporary, radiation belt around Earth — reveals how much remains unknown about outer space, even those regions closest to the planet, researchers added.
After humanity began exploring space, the first major find made there were the Van Allen radiation belts, zones of magnetically trapped, highly energetic charged particles first discovered in 1958.
"They were something we thought we mostly understood by now, the first discovery of the Space Age," said lead study author Daniel Baker, a space scientist at the University of Colorado.
These belts were believed to consist of two rings: an inner zone made up of both high-energy electrons and very energetic positive ions that remains stable in intensity over the course of years to decades; and an outer zone comprised mostly of high-energy electrons whose intensity swings over the course of hours to days depending primarily on the influence from the solar wind, the flood of radiation streaming from the sun.
The discovery of a temporary new radiation belt now has scientists reviewing the Van Allen radiation belt models to understand how it occurred.
Radiation rings around Earth
The giant amounts of radiation the Van Allen belts generate can pose serious risks for satellites. To learn more about them, NASA launched twin spacecraft, the Van Allen probes, in the summer of 2012.
The satellites were armed with a host of sensors to thoroughly analyze the plasma, energetic particles, magnetic fields and plasma waves in these belts with unprecedented sensitivity and resolution.
Unexpectedly, the probes revealed a new radiation belt surrounding Earth, a third one made of super-high-energy electrons embedded in the outer Van Allen belt about 11,900 to 13,900 miles (19,100 to 22,300 kilometers) above the planet’s surface. This stable ring of space radiation apparently formed on Sept. 2 and lasted for more than four weeks.
"The feature was so surprising, I initially foolishly thought the instruments on the probes weren’t working properly, but I soon realized the lab had built such wonderful instruments that there wasn’t anything wrong with them, so what we saw must be true," Baker said.
This newfound radiation belt then abruptly and almost completely disappeared on Oct. 1. It was apparently disrupted by an interplanetary shock wave caused by a spike in solar wind speeds.
"More than five decades after the original discovery of these radiation belts, you can still find new unexpected things there," Baker said. "It’s a delight to be able to find new things in an old domain. We now need to re-evaluate them thoroughly both theoretically and observationally."
On Aug. 31, 2012, a giant prominence on the sun erupted, sending out particles and a shock wave that traveled near Earth. This event may have been one of the causes of a third radiation belt that appeared around Earth a few days later, a phenomenon that was observed for the very first time by the newly-launched Van Allen Probes. This image of the prominence before it erupted was captured by NASA’s Solar Dynamics Observatory.
A radiation mystery
It remains uncertain how this temporary radiation belt arose. Van Allen mission scientists suspect it was likely created by the solar wind tearing away the outer Van Allen belt.
"It looks like its existence may have been bookended by solar disturbances," Baker said.
Future study of the Van Allen belts can reveal if such temporary rings of radiation are common or rare.
"Do these occur frequently, or did we get lucky and see a very rare circumstance that happens only once in a while?" Baker said. "And what other unusual revelations might come now that we are really looking at these radiation belts with new, modern tools?"
The scientists detailed their findings online Feb. 28 in the journal Science.
Sand Pirates: ISIS Are America’s 21st Century Terrorist Privateers 2014 11 01 What is ISIS? If you believe govt and corporate propaganda, you still think that ISIS is a grassroots Islamic ideological movement ¨C and with no connection to intelligence agencies like America¡¯s CIA, Britain¡¯s MI6, Turkish (NATO) intelligence, Saudi intelligence, Israeli intelligence, or Pakistan¡¯s ISI.
The reality of ISIS is something altogether different¡
On closer inspection, these marauding paramilitary ISIS gangs are nothing ...
Ancient Stone Circles in Mideast Baffle Archaeologists 2014 11 01 Huge stone circles in the Middle East have been imaged from above, revealing details of structures that have been shrouded in mystery for decades.
The Big Circle called J1 is about 390 meters (1,280 feet) in diameter, with an open area created by bulldozing in its interior.
Credit: David L. Kennedy, copyright is retained by the Aerial Photographic Archive for Archaeology ...
Sweden Recognizes Palestinian State; Israel Upset 2014 10 31
Sweden on Thursday became the biggest Western European country to recognize a Palestinian state, prompting a strong protest from Israel, which swiftly withdrew its ambassador from Stockholm.
The move by Sweden’s new left-leaning government reflects growing international impatience with Israel’s nearly half-century control of the West Bank, east Jerusalem and its blockade of the Gaza Strip. It also comes during increased ...
Fed-Backed Study: How to Brainwash Public into Fearing “Climate Change” Like Ebola 2014 10 31
$84K study seeks ways to make public fear "climate change and overpopulation"
The National Science Foundation is funding a study to determine how to brainwash the public into fearing “climate change and overpopulation” as if they were Ebola.
The NSF awarded an $84,000 grant to researchers at the State University of New York at Buffalo yesterday to figure out how to make ...
Brain decoder can eavesdrop on your inner voice 2014 10 31
As you read this, your neurons are firing – that brain activity can now be decoded to reveal the silent words in your head
TALKING to yourself used to be a strictly private pastime. That’s no longer the case – researchers have eavesdropped on our internal monologue for the first time. The achievement is a step towards helping people who cannot ...