Image:Identical Radiation Belt Storm Probes
The identical Radiation Belt Storm Probes will follow similar orbits that will take them through both the inner and outer radiation belts. The highly elliptical orbits range from a minimum altitude of approximately 373 miles to a maximum altitude of approximately 23,000 miles.
updated 8/9/2012 8:38:45 PM ET 2012-08-10T00:38:45

A pair of spacecraft in suits of armor will brave one of the toughest environments in space when they launch later this month to study radiation around Earth.

NASA's Radiation Belt Storm Probes (RBSP) will fly through the thick belts of charged particles that encircle our planet to try to understand these dynamic environments. To withstand the damage such harsh radiation can inflict, the satellites are shrouded in strong layers of shielding.

The $670 million twin probes are due to launch aboard a United Launch Alliance Atlas V rocket taking off from Cape Canaveral Air Force Station in Florida at 4:08 a.m. on Aug. 23. They will take up two slightly different orbits through the Van Allen radiation belts, regions of protons and electrons spewed out from the sun that have been trapped by Earth's magnetic field.

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The Radiation Belt Storm Probes launch is coming just weeks after one of NASA's most high-profile achievements in years: landing the huge Curiosity rover on Mars, which occurred Aug. 5 PDT.

"As cool as Mars is, it does not have a radiation belt," said Barry Mauk, RBSP project scientist based at Maryland's Applied Physics Laboratory (APL), during a news briefing Aug. 9.

Radiation shields up!
To withstand the radiation, the spacecraft will "go there in a suit of armor" made of aluminum shielding a third of an inch thick (8.5 mm), said Rick Fitzgerald, RBSP project manager, also at APL. "That makes us one of the toughest missions." [ Video: Probes to Study Radiation Threat to Astronauts ]

And the spacecraft must achieve a complicated balancing act. While they need to protect themselves from the damaging solar radiation, they must also expose their instruments to it in order to make measurements. To do this, the RBSPs will allow radiation through small controlled openings.

Both satellites house five science instruments inside their eight-sided frames, which are about 6 feet across, 3 feet high and weigh a total of 1,475 pounds each.

Mission managers have decided to launch two twin probes, instead of one, in order to take simultaneous readings at different locations, to determine whether a change in radiation levels indicates a change across time or across space.

Van Allen belt history
The Van Allen belts were discovered by American space scientist James Van Allen in 1958, but have remained largely mysterious.

"The dynamic is highly unpredictable. We know that variations in the sun cause geomagnetic storms," Mauk said. "The response of the radiation belts to those storms is highly variable. We just do not understand why that occurs."

The Radiation Belt Storm Probes will map out the density of charged particles across the belts, which are divided into two: an inner belt, and an outer. The inner belt normally extends from about 1,000 miles above Earth to 8,000 miles. After a gap, the outer belt runs from around 12,000 to 25,000 miles.

"During solar storms, lots of things happen, the belts can expand greatly," said Mona Kessel, RBSP program scientist based at NASA headquarters in Washington, D.C. "They can fill in the region between the belts and expand out."

When the belts expand, they can pose dangers to satellites orbiting Earth, and even the astronauts aboard the International Space Station, which orbits about 240 miles high (390 km).

"One satellite unfortunately could not unravel this complicated nature," Kessel added. "This is a job for RBSP."

Follow Clara Moskowitz on Twitter @ClaraMoskowitz or @Spacedotcom. We're also onFacebook & Google+.

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Photos: Month in Space: January 2014

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  1. Southern stargazing

    Stars, galaxies and nebulas dot the skies over the European Southern Observatory's La Silla Paranal Observatory in Chile, in a picture released on Jan. 7. This image also shows three of the four movable units that feed light into the Very Large Telescope Interferometer, the world's most advanced optical instrument. Combining to form one larger telescope, they are greater than the sum of their parts: They reveal details that would otherwise be visible only through a telescope as large as the distance between them. (Y. Beletsky / ESO) Back to slideshow navigation
  2. A balloon's view

    Cameras captured the Grandville High School RoboDawgs' balloon floating through Earth's upper atmosphere during its ascent on Dec. 28, 2013. The Grandville RoboDawgs’ first winter balloon launch reached an estimated altitude of 130,000 feet, or about 25 miles, according to coaches Mike Evele and Doug Hepfer. It skyrocketed past the team’s previous 100,000-feet record set in June. The RoboDawgs started with just one robotics team in 1998, but they've grown to support more than 30 teams at public schools in Grandville, Mich. (Kyle Moroney / AP) Back to slideshow navigation
  3. Spacemen at work

    Russian cosmonauts Oleg Kotov, right, and Sergey Ryazanskiy perform maintenance on the International Space Station on Jan. 27. During the six-hour, eight-minute spacewalk, Kotov and Ryazanskiy completed the installation of a pair of high-fidelity cameras that experienced connectivity issues during a Dec. 27 spacewalk. The cosmonauts also retrieved scientific gear outside the station's Russian segment. (NASA) Back to slideshow navigation
  4. Special delivery

    The International Space Station's Canadian-built robotic arm moves toward Orbital Sciences Corp.'s Cygnus autonomous cargo craft as it approaches the station for a Jan. 12 delivery. The mountains below are the southwestern Alps. (NASA) Back to slideshow navigation
  5. Accidental art

    A piece of art? A time-lapse photo? A flickering light show? At first glance, this image looks nothing like the images we're used to seeing from the Hubble Space Telescope. But it's a genuine Hubble frame that was released on Jan. 27. Hubble's team suspects that the telescope's Fine Guidance System locked onto a bad guide star, potentially a double star or binary. This caused an error in the tracking system, resulting in a remarkable picture of brightly colored stellar streaks. The prominent red streaks are from stars in the globular cluster NGC 288. (NASA / ESA) Back to slideshow navigation
  6. Supersonic test flight

    A camera looking back over Virgin Galactic's SpaceShipTwo's fuselage shows the rocket burn with a Mojave Desert vista in the background during a test flight of the rocket plane on Jan. 10. Cameras were mounted on the exterior of SpaceShipTwo as well as its carrier airplane, WhiteKnightTwo, to monitor the rocket engine's performance. The test was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventual commercial space tours.

    More about SpaceShipTwo on PhotoBlog (Virgin Galactic) Back to slideshow navigation
  7. Red lagoon

    The VLT Survey Telescope at the European Southern Observatory's Paranal Observatory in Chile captured this richly detailed new image of the Lagoon Nebula, released on Jan. 22. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of 11 public surveys of the sky now in progress using ESO telescopes. (ESO/VPHAS team) Back to slideshow navigation
  8. Fire on the mountain

    This image provided by NASA shows a satellite view of smoke from the Colby Fire, taken by the Multi-angle Imaging SpectroRadiometer aboard NASA's Terra spacecraft as it passed over Southern California on Jan. 16. The fire burned more than 1,863 acres and forced the evacuation of 3,700 people. (NASA via AP) Back to slideshow navigation
  9. Where stars are born

    An image captured by NASA's Spitzer Space Telescope shows the Orion Nebula, an immense stellar nursery some 1,500 light-years away. This false-color infrared view, released on Jan. 15, spans about 40 light-years across the region. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also can detect stars still in the process of formation, seen here in red hues. (NASA / JPL-Caltech) Back to slideshow navigation
  10. Cygnus takes flight

    Orbital Sciences Corp.'s Antares rocket rises from NASA's Wallops Flight Facility on Wallops Island, Va, on Jan. 9. The rocket sent Orbital's Cygnus cargo capsule on its first official resupply mission to the International Space Station. (Chris Perry / NASA) Back to slideshow navigation
  11. A long, long time ago...

    This long-exposure picture from the Hubble Space Telescope, released Jan. 8, is the deepest image ever made of any cluster of galaxies. The cluster known as Abell 2744 appears in the foreground. It contains several hundred galaxies as they looked 3.5 billion years ago. Abell 2744 acts as a gravitational lens to warp space, brightening and magnifying images of nearly 3,000 distant background galaxies. The more distant galaxies appear as they did more than 12 billion years ago, not long after the Big Bang. (NASA / NASA via AFP - Getty Images) Back to slideshow navigation
  12. Frosty halo

    Sun dogs are bright spots that appear in the sky around the sun when light is refracted through ice crystals in the atmosphere. These sun dogs appeared on Jan. 5 amid brutally cold temperatures along Highway 83, north of Bismarck, N.D. The temperature was about 22 degrees below zero Fahrenheit, with a 50-below-zero wind chill.

    Slideshow: The Year in Space (Brian Peterson / The Bismarck Tribune via AP) Back to slideshow navigation
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