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

The moon (Photo: NASA)

The Earth and its moon started with a big bang, according to a new theory from NASA scientists, who believe both were born out of collisions between two massive developing planets.The new theory suggests the two giant planetary bodies, each about five times the size of Mars, collided with each other twice.

After the first collision, the planets smashed into each other again, leaving behind material which resulted in our early Earth. The fledgling planet was surrounded by a disk of left-over material, which later combined to form the moon.

This new theory challenges the widely-held “giant impact hypothesis,” which suggests the moon formed early in our solar system’s history after an enormous impact between Earth and a Mars-sized planet that was still being formed.  Some call that protoplanet Theia, after the mother of the goddess of the moon in Greek mythology.

However, skeptics say if the Theia theory were true, Earth and the moon would have different chemical compositions from each other, which they don’t.

Iconic photo of the Earth and moon as seen from the Apollo 8 spacecraft while in lunar orbit on 12/24/1968. (Photo: NASA)

According to the new NASA theory, the two collisions, along with the subsequent melding of left-over material, formed both the Earth and the moon, which is why they have similar chemical compositions. “Our understanding of the solar system is constantly being refined with each new discovery,” says NASA’s Greg Schmidt. “This research illustrates the importance of modeling planetary formation to enhance our scientific understanding of the moon and its place in the solar system.”

The model which demonstrates this new theory was developed at the Southwest Research Institute (SwRI), in San Antonio, Texas by Robin M. Canup.

Canup says her work was inspired by previous studies on the early history of the moon, which explain the similar chemical composition of the Earth and moon, while at the same time producing an appropriate mass for Earth and the moon.

“The ultimate likelihood of each impact scenario will need to be assessed by improved models of terrestrial planet formation,” Canup said.  Canup’s work is outlined in Science.

Video: A computer simulation of a low-velocity collision of two protoplanets that contain 45 and 55 percent of the Earth’s mass. Colors indicate particle temperature in kelvin, with blue-to-red indicating temperatures from 2,000 K to in excess of 6,440 K. After the first protoplanetary impact, they re-collide, merge and form a rapidly spinning Earth-mass planet that is surrounded by a disk of particles that would later form the Moon. (Video: Southwest Research Institute)

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.

Photo: NASA/JPL

Looking up at the Moon from our blue planet Earth, it’s hard to see anything other than a barren landscape.  Devoid of any life, it’s a visual study in dusty shades of gray.

But recently scientists from Case Western Reserve University, the Carnegie Institution for Science, and Brown University have found that parts of the Moon’s interior contains as much water as the upper mantle of the Earth, more than 100 times what was measured before.

Examining moon material brought back to earth back in 1972 by the US Apollo 17 mission, the researchers were able to find water along with other volatile elements such as fluorine, chlorine and sulfur.

One of the scientists involved with this discovery is James Van Orman, a professor of geological studies at Case Western Reserve in Cleveland, Ohio.  “These samples provide the best window we have to the amount of water in the interior of the Moon,” says Van Orman.  “The interior seems to be pretty similar to the interior of the Earth, from what we know about water abundance.”

This discovery seems to strengthen the theory that the Moon and Earth have a common origin but at the same time may force scientists to reconsider the current theory of the process: that a huge impact in Earth’s early history ejected material into orbit that became the Moon.

Published in the May 26 edition of Science Express, this finding is said to challenge previously made assumptions on how the Moon came to be and provides new clues into the process of lunar formation.