World Bulletin / News Desk
When NASA scientists launched twin spacecraft to probe the Van Allen radiation belts last summer, they were expecting to study two rings of high-energy particles circling Earth. Instead they found three, overturning a 50-year-old model of the giant rings’ structure, reported scientificamerican.com.
First discovered in 1958, the Van Allen belts have been thought to comprise two reservoirs of high-speed, electrically charged particles, corralled into separate doughnut-shaped rings by Earth’s magnetic field. The outer ring orbits at a distance of some 10,000–60,000 kilometers above Earth, and encircles an inner band of even more energetic particles, roughly 100–10,000 kilometers above Earth. That’s the configuration the belts were in when James Van Allen first spotted them using satellite data half a century ago, and that’s also the structure that NASA’s twin Van Allen Probes recorded when they began operation on 1 September 2012.
But just two days later, telescopes on the probes revealed the emergence of an additional, narrow belt of charged particles sandwiched between the inner ring and a now highly eroded outer ring. “It was so unexpected that we thought there was something wrong with the instrument,” says Daniel Baker, a space physicist at the University of Colorado in Boulder.
The new ring persisted, however, and Baker and his team now attributes its creation to an interplanetary shock wave — a traveling outburst of solar-wind particles from the Sun — that has been detected by other craft. The shock wave scoured away much of the outer ring and then divided the remains into two distinct sections, he suggests.
For nearly all of September, the middle ring remained while the outer ring continued to wax and wane. On 1 October, however, another interplanetary shock wave, more energetic than the previous one, obliterated both the outer and middle rings, leaving only the inner Van Allen belt intact. Seven or eight days later, a third shock wave somehow restored the original structure of the two belts as depicted in textbooks, Baker says.
Baker goes on to say that data collected by the probes on 9 October revealed that “suddenly the whole outer belt was lit up again but with the [middle] ring gone.”
Most industry experts expect the first product of 5G technology in the run-up to the Tokyo Olympics in 2020.
The slowdown in the rate of rising temperatures, from faster gains in the 1980s and 1990s, has puzzled scientists because heat-trapping greenhouse gas emissions
The discovery challenges currently held theories that black holes and their host galaxies grew in relative lockstep over the eons.
Australian researchers are developing the new way to have a final product for Boeing Co, Airbus Group NV, very quickly than now. 3D printing can cut production times for components from three months to just six days.
Bogachev is charged in the United States with running a computer attack network called GameOver Zeus that allegedly stole more than $100 million from online bank accounts.
The account started sharing videos and photos of the militant group a few days ago
U.S., UK spies hacked SIM card maker Gemalto's system, Intercept says, giving spies ability to monitor calls on billions of phones
The next time an earthquake hits the Pacific Northwest, a handful of computers in offices across the region will have access to a software that will send out an alarm, alerting people before the earthquake strikes.
Researchers in Britain have discovered that limpet teeth exhibit a strength that is potentially higher than spider silk.
Epigenetic differences are one reason identical twins, who have identical DNA, do not always develop the same genetic diseases, including cancer.
Kaspersky said it found personal computers in 30 countries infected with one or more of the spying programs, with the most infections seen in Iran, followed by Russia, Pakistan, Afghanistan, China, Mali, Syria, Yemen and Algeria.
The makers of mobile travel app "Bey2ollak" have warn on bomb scares and resulting hold-ups in Cairo and Alexandria using the hashtag #WhereIsTheBomb.
The preschool programme, aimed at children aged between three and six, is based on the Finnish National Curriculum, widely considered one of the world's best education systems.
Kansai Electric is aiming to start the reactors by November, according to a plan submitted to the government to raise electricity prices, a spokesman said on Thursday.
European Space Agency's (ESA) Intermediate eXperimental Vehicle (IXV) size of a car.