A new radiation belt has been discovered around Earth. It is shown here using actual data as the middle arc of orange and red of the three arcs seen on each side of the Earth. (Image: JHUAPL/LASP)

NASA scientists have discovered a third radiation belt briefly surrounded Earth for about a month before being blasted away by an interplanetary shock wave from the sun.

Experts had long thought there were only two distinct regions of trapped radiation. But the third ring was spotted by twin Van Allen radiation probes NASA launched in 2012 to study the radiation belts which encircle Earth and can be hazardous to orbiting satellites and astronauts.

“This is the first time we have had such high-resolution instruments look at time, space and energy together in the outer belt,” said Daniel Baker from the University of Colorado in Boulder, who is lead author of the study. ”Previous observations of the outer radiation belt only resolved it as a single blurry element. When we turned REPT [the Relativistic Electron Proton Telescope] on just two days after launch, a powerful electron acceleration event was already in progress, and we clearly saw the new belt and new slot between it and the outer belt.”

According to mission scientists, the discovery demonstrates radiation belts are dynamic and flexible in nature, which provides a better understanding of how they respond to solar activity.

However, the discovery might not have occurred had scientists followed standard operating procedures.

Artist rendering of the twin Van Allen probes in orbit within Earth’s magnetic field. (Image: JHU/APL)

Anxious and excited mission scientists turned on a critical piece of equipment soon after it was launched into space aboard the probe.  Usually, standard operating procedures for most NASA science missions call for a waiting period that can take months. After that, instruments are slowly turned on and activated one at a time, as technicians slowly ramp them up to full power.

If scientists working with the Van Allen probes mission had followed that set of procedures, the third Van Allen belt might never have been spotted. Data sent back to Earth from the probes throughout the month of September at first showed the two expected Van Allen belts.

But a few days later, the scientists noticed  the belt’s outer ring seemed to be squeezing into an intense, tightly packed band of electrons and that a third, less compact belt of electrons formed further out, creating a total of three rings.

Named after the noted physicist, James Van Allen, the man who discovered them in 1958, the Van Allen radiation belts are two, and now sometimes three, layers of trapped radiation from solar winds or cosmic rays held in place by Earth’s magnetic fields.

Earth’s magnetic fields, which come from our planet’s inner core, repel most harmful radiation away from us, keeping it high above Earth where it accumulates in the Van Allen belts.

Graphic of the Van Allen belts (NASA)

These layers of radiation are greatly affected by space weather and expand and contract depending upon the amount of energy sent to Earth from the sun and elsewhere.

The Van Allen belts can extend into space from an altitude of about 1,000 to 60,000 kilometers above the Earth’s surface.  The belt closest to Earth is called the inner belt. It’s separated from the outer belt by  an empty region of space.  This gap between the two Van Allen belts is caused by low-frequency radio waves that eject energy particles which would otherwise accumulate there.

Scientists have said there are times, when the sun erupts, that particles force their way into the gap, but soon disappear after a few days.

The Van Allen probes mission includes two spacecraft packed with identical instruments so that simultaneous measurements can be taken from different locations within the radiation belts.

“The fantastic new capabilities and advances in technology in the Van Allen Probes have allowed scientists to see in unprecedented detail how the radiation belts are populated with charged particles and will provide insight on what causes them to change, and how these processes affect the upper reaches of Earth’s atmosphere,” said John Grunsfeld, NASA’s associate administrator for science.

Van Allen Probes Discovery – NASA Video

Fragments of the Sutter’s Mill meteorite fall collected by astronomer Dr. Peter Jennisken. (NASA)

Researchers have struck scientific gold at Sutter’s Mill, site of the famed California Gold Rush where the precious metal was first discovered in 1848.

In April of this year, the scientists recovered a rare meteorite which contains clues to the early history of the solar system.

Using Doppler radar, the same technology used by weather forecasters, the scientists detected a shower of meteors raining down over the communities of Coloma and Lotus, just after the asteroid broke up in the atmosphere.

That allowed scientists to, for the first time,  quickly find, recover and study a primitive meteorite that had little exposure to the elements.

It’s the most pristine look at the surface of ancient asteroids scientists have been able to study so far. Because of the rapid recovery of materials, scientists were able to detect compounds that quickly disappear once a meteorite hits Earth.

Reporting in Science, the researchers say their rare find was classified as a Carbonaceous-Mighei or CM-type carbonaceous chondrite meteorite, which is known to contain water and complex organic compounds, such as amino acids, molecules that help form life.

But, according to NASA’s Danny Glavin, he and the other scientists weren’t able to detect many of the amino acids in their find because it appeared the samples had been heated in space before arriving on Earth.

“The small three meter-sized asteroid that impacted over California’s Sierra Nevada came in at twice the speed of typical meteorite falls,” said lead author Peter Jenniskens, of the SETI Institute and NASA’s Ames Research Center, both located in California. “Clocked at 64,000 miles per hour, it was the biggest impact over land since the impact of the four meter-sized asteroid 2008 TC3, four years ago over Sudan.”

The scientists also say that, for the first time, they were able to identify the region of space where these types of meteorites come from.

After studying photographs and video of the asteroid, Jenniskens figured that it came in on an unusually low-angled orbit, more like a comet‘s orbit, passing closer to the sun than what has been learned from past recorded meteorite falls.

Scientists found the asteroid, as it was in orbit, was influenced by the gravity of both the Sun and Jupiter at times.

“It circled the sun three times during a single orbit of Jupiter, in resonance with that planet,” Jenniskens said.

A meteor flashes across the sky during the peak of the November 2009 Leonid Meteor Shower. (Photo: Ed Sweeney via Wikimedia Commons)

The asteroid that spawned the meteorite was estimated to be around 45359 kg.  Of that, less than 1kg was actually recovered on the ground in the form of 77 tiny meteorites. The biggest of those meteorites was 205 grams.

While the scientists didn’t find much actual gold in the Sutter’s Mill meteorite, about 150 parts per billion, it was still “scientific gold,” according to co-author and cosmochemist Qing-zhu Yin of the University of California at Davis.

“With 78 other elements measured, Sutter’s Mill provides one of the most complete records of elemental compositions documented for such primitive meteorites,” he said.

This June 8, 2004 photo shows the transit of Venus, which occurs when the planet Venus passes between the Earth and the sun, pictured in Hong Kong. (AP Photo/Vincent Yu,File)

On Tuesday,  June 5, people in most parts of the world have a good chance of witnessing a once-in-a-lifetime astronomical event called the transit of Venus.

It’s a planetary alignment which occurs when the planet Venus passes directly between the Earth and sun.

For those of us here on Earth, it’ll look like a little black dot beginning on the edge of the sun and gliding across the face of it over a couple of hours.

The transit of Venus is expected to occur at around 2209 UTC.  Of course,  clouds could obscure the view and people in Portugal, southern Spain, western Africa, and the portions of South America are unlikely to see the occurrence because that part of the world will be in total darkness the entire time of the transit.

The striking event occurs about once a century, in pairs, with around eight years separating each twin event.  This upcoming occurrence is the second in a recent pair of events, the first of which took place in 2004.

Tomorrow’s transit will mark only the seventh time the phenomenon has been seen since it was first observed in 1639 by Jeremiah Horrocks and William Crabtree of England.

In 1627, astronomer Johannes Kepler became the first person to successfully forecast a transit of Venus when he predicted the 1631 event.

According to NASA, the 18th century astronomer, Edmund Halley – of Halley’s Comet fame – came up with a way of using the transit of Venus to determine the distance between Earth and the sun. He suggested  measuring the start and end times of the transit from different points on Earth, using methods of triangulation to make the calculation.

The method was first tried in 1761, but the international team’s efforts were unsuccessful due to poor weather and other factors.

If you want to watch the transit of Venus be sure to take precautionary measures. These people, for example are using solar viewing glasses to safely view the Sun. (Photo: NASA)

Another effort, in 1769,  with observation points all over the world, proved more successful, providing statistical data that led scientists to calculate the mean distance from the Earth to the sun was around 150,838,824 kilometers. Using more modern, technologically-advanced equipment, scientists now say the mean distance from the Earth to sun is 149,600,000 kilometers. Seems that, with Sir Edmund Halley’s help, the 18th century calculations were pretty darn close.

Speaking of NASA, the space agency announced that Don Pettit, a flight engineer on the International Space Station, will photograph the event. It’s the first time the transit of Venus has been observed from space.  The astronauts aboard the ISS in 2004 weren’t able to see the transit because they didn’t have any solar filters which would allow them to safely observe it.

Observatories and other various science-oriented institutions from around the world will be opening their doors to host transit watching parties and events.

World map show visibility of transit of Venus on June 5-6, 2012. (Map: Michael Zeiler)

If you’re planning on watching the transit of Venus, please make sure to take precautions, since looking at the sun directly can cause serious damage to your eyes.  Experts recommend you use protective glasses or telescope lenses with special solar filters, or better yet, watch it on TV or the Web.  Good luck with your observations because the next set of transits won’t take place until 105 years from now, in 2117.