Van Allen Probes: Radiation Belt Storm Probes (RBSP)

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Van Allen Probes: Radiation Belt Storm Probes (RBSP)

Post by bystander » Thu Jul 19, 2012 2:15 am

The Electric Atmosphere: Plasma Is Next NASA Science Target
NASA | Radiation Belt Storm Probes (RBSP) | 2012 July 18
Click to play embedded YouTube video.
Click to play embedded YouTube video.
Click to play embedded YouTube video.
Our day-to-day lives exist in what physicists would call an electrically neutral environment. Desks, books, chairs and bodies don't generally carry electricity and they don't stick to magnets. But life on Earth is substantially different from, well, almost everywhere else. Beyond Earth's protective atmosphere and extending all the way through interplanetary space, electrified particles dominate the scene. Indeed, 99% of the universe is made of this electrified gas, known as plasma.

Two giant donuts of this plasma surround Earth, trapped within a region known as the Van Allen Radiation Belts. The belts lie close to Earth, sandwiched between satellites in geostationary orbit above and satellites in low Earth orbit (LEO) are generally below the belts. A new NASA mission called the Radiation Belt Storm Probes (RBSP), due to launch in August 2012, will improve our understanding of what makes plasma move in and out of these electrified belts wrapped around our planet.

"We discovered the radiation belts in observations from the very first spacecraft, Explorer 1, in 1958" says David Sibeck, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., and the mission scientist for RBSP. "Characterizing these belts filled with dangerous particles was a great success of the early space age, but those observations led to as many questions as answers. These are fascinating science questions, but also practical questions, since we need to protect satellites from the radiation in the belts."

The inner radiation belt stays largely stable, but the number of particles in the outer one can swell 100 times or more, easily encompassing a horde of communications satellites and research instruments orbiting Earth. Figuring out what drives these changes in the belts, requires understanding what drives the plasma.

Plasmas seethe with complex movement. They generally flow along a skeletal structure made of invisible magnetic field lines, while simultaneously creating more magnetic fields as they move. Teasing out the rules that govern such a foreign environment – one that can only be studied from afar – lies at the heart of understanding a range of events that make up space weather, from giant explosions on the sun to potentially damaging high energy particles in near-Earth environs.

To distinguish between a host of theories developed over the years on plasma movement in those near-Earth environs, RBSP scientists have designed a suite of instruments to answer three broad questions. Where do the extra energy and particles come from? Where do they disappear to, and what sends them on their way? How do these changes affect the rest of Earth's magnetic environment, the magnetosphere? In addition to its broad range of instruments, the RBSP mission will make use of two spacecraft in order to better map out the full spatial dimensions of a particular event and how it changes over time.

Scientists want to understand not only the origins of electrified particles – possibly from the solar wind constantly streaming off the sun; possibly from an area of Earth's own outer atmosphere, the ionosphere – but also what mechanisms gives the particles their extreme speed and energy.

"We know examples where a storm of incoming particles from the sun can cause the two belts to swell so much that they merge and appear to form a single belt," says Shri Kanekal, RBSP's deputy project scientist at Goddard. "Then there are other examples where a large storm from the sun didn't affect the belts at all, and even cases where the belts shrank. Since the effects can be so different, there is a joke within the community that 'If you've seen one storm . . . You've seen one storm.' We need to figure out what causes the differences."

There are two broad theories on how the particles get energy: from radial transport or in situ. In radial transport, particles move perpendicular to the magnetic fields within the belts from areas of low magnetic strength far from Earth to areas of high magnetic strength nearer Earth. The laws of physics dictate that particle energies correlate to the strength of the magnetic field, increasing as they move towards Earth. The in situ theory posits that electromagnetic waves buffet the particles -- much like regular pushes on a swing -- successively raising their speed (and energy).

As for how the particles leave the belts, scientists again agree on two broad possibilities: particles go up, or they go down. Perhaps they travel down magnetic field lines toward Earth, out of the belts into the ionosphere, where they stay part of Earth's magnetic system with the potential to return to the belts at some point. Or they are transported up and out, on a one-way trip to leave the magnetosphere forever and enter interplanetary space.

"In reality, the final answers may well be a combination of the basic possibilities," says Sibeck. "There may be, and probably are, multiple processes at multiple scales at multiple locations. So RBSP will perform very broad measurements and observe numerous attributes of waves and particles to see how each event influences others."

To distinguish between the wide array of potential theories – not to mention combinations thereof – the instruments on RBSP will be equipped to measure a wide spectrum of information. RBSP will measure a host of different particles, including hydrogen, helium and oxygen, as well as measure magnetic fields and electric fields throughout the belts, both of which can guide the movement of these particles.

RBSP will also measure a wide range of energies from the coldest particles in the ionosphere to the most energetic, most dangerous particles. Information about how the radiation belts swell and shrink will help improve models of Earth's magnetosphere as a whole.

"Particles from the radiation belts can penetrate into spacecraft and disrupt electronics, short circuits or upset memory on computers," says Sibeck. "The particles are also dangerous to astronauts traveling through the region. We need models to help predict hazardous events in the belts and right now we are aren’t very good at that. RBSP will help solve that problem."

While the most immediate practical need for studying the radiation belts is to understand the space weather system near Earth and to protect humans and precious electronics in space from geomagnetic storms, there is another reason scientists are interested in this area. It is the closest place to study the material, plasma, that pervades the entire universe. Understanding this environment so foreign to our own is crucial to understanding the make up of every star and galaxy in outer space.

The Johns Hopkins University Applied Physics Laboratory (APL) built and will operate the twin RBSP spacecraft for NASA’s Living With a Star program, which is managed by Goddard Space Flight Center for NASA’s Science Mission Directorate.

http://rbsp.jhuapl.edu/
http://www.nasa.gov/rbsp

The Van Allen Belts and the Great Electron Escape
Universe Today | Tammy Plotner | 2012 Jan 31
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New NASA Mission Ready to Brave Earth's Radiation Belts

Post by bystander » Sat Aug 11, 2012 3:52 am

New NASA Mission Ready to Brave Earth's Radiation Belts
NASA | JHU-APL | 2012 Aug 09
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NASA's Radiation Belt Storm Probes (RBSP) mission will send two spacecraft into the harsh environment of our planet's radiation belts. Final preparations have begun for launch on Thursday, Aug. 23, from Florida's Space Coast.

The RBSP spacecraft are designed to fly and operate in the heart of the most hazardous regions of near-Earth space to collect crucial data. The data will help researchers develop an understanding of the Van Allen radiation belts, two rings of very high energy electrons and protons that can pose hazards to human and robotic explorers.

"At the end of this month we will turn our attention from planet Mars to planet Earth, both immersed in the atmosphere of our sun," said Barbara Giles, director of NASA's Heliophysics Division. "RBSP will further explore the connection of solar variability and its impacts on Earth's radiation belts."

RBSP will help scientists understand how the invisible radiation belts -- named for James Van Allen, who discovered them -- behave and react to changes in the sun, thereby contributing to Earth's space weather. Space weather is caused in great part by the sun's influence on Earth and near-Earth space, including solar events such as giant eruptions of solar material called coronal mass ejections.

"The dramatic dynamics of Earth's radiation belts caused by space weather are highly unpredictable," said Barry Mauk, RBSP project scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md. "One of the fundamental objectives of the RBSP mission is to use Earth's magnetosphere as a natural laboratory to understand generally how radiation is created and evolves throughout the universe. There are many mysteries that need to be resolved."

Space weather fluctuations can increase radiation exposure for pilots and passengers during polar aircraft flights. They also can disable satellites, cause power grid failures, and disrupt the Global Positioning System, television and telecommunications signals. Understanding the science of space weather will lead to better space weather predictions, which in turn will allow us to better manage and protect our technological infrastructure in space and on the ground.

The spacecraft are atop a United Launch Alliance Atlas V rocket currently being prepared to lift off from Cape Canaveral Air Force Station, Fla.

"Everything is ready and prepared for RBSP to launch as scheduled," said Richard Fitzgerald, RBSP project manager at APL. "Both the twin spacecraft and the entire RBSP team are eager to begin their exploration of one of the most dangerous parts of space near our planet."

The mission will last two years. The spacecraft, carrying the best and most comprehensive instrumentation ever sent into the radiation belts, will fly through surging and swelling belts of energized particles that would damage ordinary spacecraft. By using a pair of probes flying in highly elliptical orbits, scientists will be able to study the radiation belts over space and time, learn how particles within the belts are produced and behave during space weather events, and what mechanisms drive the acceleration of the particles.

RBSP is part of NASA's Living With a Star Program to explore aspects of the connected sun-Earth system that directly affect life and society. LWS is managed by the agency's Goddard Space Flight Center in Greenbelt, Md. APL built the RBSP spacecraft and will manage the mission for NASA.

For more information about NASA's RBSP mission, visit: http://www.nasa.gov/rbsp
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RBSP Launch Delay, Now Set for Friday, Aug. 24

Post by bystander » Mon Aug 20, 2012 7:27 pm

RBSP Launch Delay, Now Set for Friday, Aug. 24
The launch of an Atlas V carrying NASA’s Radiation Belt Storm Probes satellite is being delayed 24 hours. An anomalous engine condition was identified during testing of another Atlas vehicle at the Factory in Decatur, Ala., and the delay will allow additional time for engineers to complete their assessments and verify that a similar condition does not exist on the RBSP launch vehicle engine.

The launch is rescheduled for Friday, Aug. 24 from Space Launch Complex-41 at Cape Canaveral Air Force Station, Fla. The opening of the launch window is 4:07 a.m. EDT. The forecast for Aug. 24 shows a 60 percent chance of favorable weather conditions for the launch.
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RBSP Launch Rescheduled for Aug. 25

Post by bystander » Fri Aug 24, 2012 10:09 pm

RBSP Launch Rescheduled for Aug. 25
Launch managers at Cape Canaveral Air Force Station in Florida have scrubbed the planned liftoff of the United Launch Alliance Atlas V carrying NASA's Radiation Belt Storm Probes due to an issue with Eastern Range beacon indications. The next launch attempt is scheduled for tomorrow, Aug. 25, at 4:07 a.m. EDT. Like today, the launch window will extend for 20 minutes.

They better hurry before Isaac closes in. Although I don't think Isaac poses a direct threat to Cape Canaveral, winds, cloud cover and rain could get heavy.




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RBSP Launch Postponed Until Aug. 30

Post by bystander » Sat Aug 25, 2012 9:04 pm

RBSP Launch Postponed Until Aug. 30
The launch of an Atlas V carrying NASA’s Radiation Belt Storm Probes (RBSP) payload was scrubbed today due to weather conditions associated with lightning, as well as cumulus and anvil clouds. With the unfavorable weather forecast as a result of Tropical Storm Isaac, the leadership team has decided to roll the Atlas V vehicle back to the Vertical Integration Facility to ensure the launch vehicle and twin RBSP spacecraft are secured and protected from inclement weather. Pending approval from the range, the launch is rescheduled to Thursday, Aug. 30 at 4:05 a.m. Eastern Daylight Time.
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RBSP Launches Successfully - Twin Probes are Healthy

Post by bystander » Thu Aug 30, 2012 4:54 pm

RBSP Launches Successfully - Twin Probes are Healthy as Mission Begins
NASA | RBSP | 2012 Aug 30
Click to play embedded YouTube video.
NASA's Radiation Belt Storm Probes are flying in Earth orbit after a successful liftoff and ascent this morning. The probes launched aboard a United Launch Alliance Atlas V rocket at 4:05 a.m. EDT after a smooth countdown at Cape Canaveral Air Force Station in Florida. The probes were released from the rocket's Centaur upper stage one at a time and sent off into different orbits, kicking off the two-year mission to study Earth's radiation belts.

"I'm very happy to report that we have two happy spacecraft on orbit," said Rick Fitzgerald, RBSP project manager from the John Hopkins University Applied Physics Laboratory, which is managing the mission for NASA. "Many thanks to ULA and Launch Services Program for getting us on orbit, giving us a great ride and injecting us in exactly the orbit that we wanted to be in."

During the RBSP mission, the identical twin spacecraft will fly in separate orbits throughout the inner and outer Van Allen radiation belts that encircle the Earth. The sun influences the behavior of the radiation belts, which in turn can impact life on Earth and endanger astronauts and spacecraft in orbit.

"Today, 11 years of hard work was realized by the science team as a number of us stood together watching the rocket lift off the pad," said Nicky Fox, RBSP deputy project scientist from APL. "(The spacecraft) are now at home in the Van Allen belts where they belong, and we can all finally breathe out now that solar panels are out on both of them."

The spacecraft will go through a 60-day commissioning period before beginning its prime mission.

"Now that the spacecraft are safely in orbit, the real fun begins," said Mike Luther, deputy associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. "After the commissioning period, we get to then begin to perform the most detailed study of Earth's radiation belts that's ever been undertaken."

NASA Launches Radiation Belt Storm Probes Mission
NASA HQ | 2012 Aug 30

Probes Launched Into Earth's Radiation Zone
Discovery News | Irene Klotz | 2012 Aug 30

NASA Launches Twin Probes to Study Earth’s Radiation Belts
Universe Today | Nancy Atkinson | 2012 Aug 30
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Science@NASA: The Radiation Belt Storm Probes

Post by bystander » Thu Aug 30, 2012 5:14 pm

The Radiation Belt Storm Probes
NASA Science News | Dr. Tony Phillips | 2012 Aug 30
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Since the dawn of the Space Age, mission planners have tried to follow one simple but important rule: Stay out of the van Allen Belts. The two doughnut-shaped regions around Earth are filled with “killer electrons,” plasma waves, and electrical currents dangerous to human space travelers and their spacecraft. Lingering is not a good idea.

So much for the old rules. NASA has launched two spacecraft directly into the radiation belts--and this time they plan to stay a while.

NASA's Radiation Belt Storm Probes blasted off from Cape Canaveral on August 30th, 2012. Bristling with sensors, the heavily-shielded spacecraft are on a 2-year mission to discover what makes the radiation belts so dangerous and so devilishly unpredictable.

"We've known about the Van Allen Belts for decades yet they continue to surprise us with unexpected storms of 'killer electrons' and other phenomena," says mission scientist David Sibeck, "The Storm Probes will help us understand what's going on out there."

When the radiation belts were discovered in 1958, they upended orthodox ideas. Most people assumed the space around Earth was empty. America's first satellite, Explorer 1, proved otherwise. The tiny spacecraft was equipped with a Geiger tube for counting energetic protons and electrons. Circling Earth, Explorer 1 found so many charged particles that the counter registered off-scale most of the time.

Back in the 1950s the radiation belts had little effect on ordinary people. Today they are crucial to our high-tech society. Hundreds of satellites used for everything from weather prediction to GPS to television routinely skim the belts, subjecting themselves to energetic particles that can damage solar panels and short-circuit sensitive electronics. During geomagnetic storms when the belts are swollen by solar activity, whole fleets of satellites can be engulfed, imperiling the technological underpinnings of daily life on the planet below.

"The Radiation Belt Storm Probes directly address these down-to-Earth problems," says Lika Guhathakurta, the lead program scientist of NASA's Living with a Star Program, which manages the mission. "RBSP is a unique mix of pure science and practical application."

One of the biggest mysteries of the radiation belts is the crazy way they react to solar storms.

"Almost anything can happen," says Sibeck.

When a storm cloud from the sun hits the radiation belts, they often respond in counterintuitive ways. One possible outcome is that the radiation belts fill with energetic particles such as the potent "killer electrons" that worry mission planners. However, just as often the opposite happens. A solar storm can cause the belts to lose their killer particles, temporarily making them a safer place. And sometimes nothing happens! The belts remain completely unchanged.

"The problem is, there is no unified idea of what phenomena are most important inside the belts," says Sibeck. He describes attending scientific conferences on the subject: "If there are 100 people at a meeting, there will be 100 different answers for every question. How are killer electrons energized? Some say plasma waves do it; others point to solar wind shocks; others favor diffusion. The list goes on and on."

Researchers hope RBSP will narrow the possibilities. During storms, the probes can sample electric and magnetic fields, count the number of energetic particles, and detect plasma waves of many frequencies. The inner workings of the Van Allen Belts will be an open book to the two spacecraft, providing data for predictive models that tell forecasters when it’s safe to enter the belts, perform spacewalks, and operate sensitive electronics.

“The Van Allen Belts are part of our home in space,” adds Guhathakurta. “RBSP will help us learn how to live there.”

So much for the old rules, indeed.

Probing the Electric Space Around Earth
NASA Earth Observatory | 2012 Aug 30
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Science@NASA: RBSP Records 'Earthsong'

Post by bystander » Tue Oct 02, 2012 3:23 am

NASA Spacecraft Records 'Earthsong'
NASA Science News | Dr. Tony Phillips | 2012 Oct 01
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Earthsong: Chorus (Audio Clip)

In space, they say, no one can hear you scream.

Nobody ever said anything about singing, though. A NASA spacecraft has just beamed back a beautiful song sung by our own planet.

"It's called chorus," explains Craig Kletzing of the University of Iowa. "This is one of the clearest examples we've ever heard."

Chorus is an electromagnetic phenomenon caused by plasma waves in Earth's radiation belts. For years, ham radio operators on Earth have been listening to them from afar. Now, NASA's twin Radiation Belt Storm Probes are traveling through the region of space where chorus actually comes from--and the recordings are out of this world.

"This is what the radiation belts would sound like to a human being if we had radio antennas for ears," says Kletzing, whose team at the University of Iowa built the “EMFISIS” (Electric and Magnetic Field Instrument Suite and Integrated Science) receiver used to pick up the signals.

He's careful to point out that these are not acoustic waves of the kind that travel through the air of our planet. Chorus is made of radio waves that oscillate at acoustic frequencies, between 0 and 10 kHz. The magnetic search coil antennas of the Radiation Belt Storm Probes are designed to detect these kinds of waves.

"Chorus emissions are front and center for the Storm Probe mission," says Kletzing. "They are thought to be one of the most important waves for energizing the electrons that make up the outer radiation belt."

In particular, chorus might be responsible for so-called "killer electrons," high-energy particles that can endanger both satellites and astronauts. Many electrons in the radiation belts are harmless, with too little energy to do damage to human or electronic systems. But, sometimes, these electrons can catch a chorus wave, like a surfer riding a wave on Earth, and gain enough energy to become dangerous—or so researchers think.

The Radiation Belt Storm Probes are on a mission to find out for sure.

“The production of killer electrons is a matter of much debate, and chorus waves are only one possibility,” notes the Storm Probes’ mission scientist Dave Sibeck.

Launched in August 2012, the two probes are orbiting inside the radiation belts, sampling electromagnetic fields, counting the number of energetic particles, and listening to plasma waves of many frequencies.

“We hope to gather enough data to solve the mystery once and for all,” says Sibeck.

At the moment, the spacecraft are still undergoing their 60-day checkout phase before the main mission begins. So far, things are checking out very well.

“One of things we noticed right away is how clear the chorus sounds in the recording,” notes Kletzing. That's because our data is sampled at 16 bits, the same as a CD, which has not been done before in the radiation belts. This makes the data very high quality and shows that our instrument is very, very healthy.”

Eventually, Kletzing hopes to release unprecedented stereo recordings of Earth’s chorus.

“We have two spacecraft with two receivers,” he says, “so a stereo recording is possible.”

Such a recording would not only sound wonderful, but also have real scientific value. “One of the things we don't know is how broad the region is over which chorus occurs. The widely-separated ‘stereo capability’ of the Storm Probes will give us the ability to figure this out,” he explains.

With a two-year mission planned for the Storm Probes, the chorus is just getting started.

The song of killer electrons
Discover Blogs | Bad Astronomy | 2012 Oct 01
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Attack of the Killer Electrons

Post by neufer » Sun Oct 07, 2012 8:12 pm

http://www.nasa.gov/vision/universe/solarsystem/killer_electrons.html wrote:
<<"Killer electrons"?! Should you be hiding under a table?

Probably not. Killer electrons are what scientists call the electrons trapped in Earth's outer radiation belt that can damage or "kill" satellites. Many satellites that have flown through the Van Allen radiation belts have confirmed their existence and measured them. Killer electrons have been blamed for many spacecraft failures. Because they zip around at nearly light speed, these particles pack a lot of punch. Each killer electron particle may have close to a thousand times more energy than you receive in a dental X-ray! So you can see how a large increase in the number of them could result in serious harm to spacecraft. Killer electrons easily penetrate thick shielding and bury themselves in the insulation around sensitive satellite electronics. Electricity from these accumulating electrons builds up in the spacecraft, and a strong internal electrical discharge can occur - a miniature lightning strike. The 2003 "Halloween storm", one of the strongest solar storms on record, temporarily shut down one Mars-bound spacecraft and permanently damaged instruments on two others. It also may have caused the complete loss of two orbiting Japanese satellites. Since spacecraft systems can't be shielded from them, they have to be able to survive an "Attack of the Killer Electrons". To design this kind of tough system, engineers need to understand more about the radiation effects from these particle events than we do now. Scientists will be coordinating data from over a dozen current and future spacecraft in the magnetosphere. This will lead us to a better understanding of how killer electrons are accelerated, why the acceleration occurs when it does, and how the particles fade away after an event. There is a lot left to learn.

Now why should you care? Since they damage satellites, killer electrons can cause problems with your telephone, cell phone, or television picture. Pager service and GPS interruptions also affect millions of people. The degree of the effects depends on the strength of the killer electron event, of course. As technology systems depend more on satellites, you can expect these little powerhouses to become even more important to you.

Electrically charged particles - both electrons and ions (an atom that has lost or gained an electron) - have accumulated in our planet's magnetic field, the magnetosphere. These particles of varying energies make up the radiation belts. The belts are invisible doughnut-shaped areas ringing the equator above our atmosphere.

Killer electrons are found in the outer of the two belts. (Ions collect mostly in the inner belt and can also damage spacecraft.) The outer belt is highest above Earth at the equator, usually at an altitude of 13,000 to 19,000 km (8,000 to 12,000 miles), where many spacecraft are positioned. GPS (Global Positioning System) satellites are found there, for example. But intense solar activity can push it in much closer and impair even more satellites.

The Sun has both calm and stormy times much like our own changing weather, and we are affected by many of these changes. These effects on Earth's environment, such as magnetic storms, are called space weather. The solar activity that creates these storms - coronal mass ejections or flares directed toward Earth - is a major source of energy to electrons in the outer belt. But particle clouds from coronal holes may be an even more important source. Coronal holes are regions from which high-speed streams of charged particles escape from the Sun through open magnetic field lines, mostly near the Sun's equator. Coronal holes generally increase as we approach the minimum in the 11-year solar cycle, often called the sunspot cycle, when the sunspot number is decreasing.

Because the amount and type of solar activity varies over time, the number of particles in the belts changes constantly over minutes, days, seasons, and the solar cycle. We see the largest numbers of killer electrons - sometimes a thousand times more - at the peak of a magnetic storm and in the following days. But scientists puzzle over the unpredictable response of the outer belt to magnetic storms: the number of electrons may increase, decrease, or not change at all.

Along with the Sun, Earth's upper atmosphere continuously supplies low-energy electrons to the outer belt. Scientists believe that the killers are created right there in the belt, when those low-energy particles are accelerated to high speeds and therefore high energy. We don't know what causes that acceleration, but powerful solar activity may energize the magnetosphere enough to do it.>>
Art Neuendorffer

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Re: Attack of the Killer Electrons

Post by dougettinger » Mon Oct 08, 2012 4:19 pm

neufer wrote:
http://www.nasa.gov/vision/universe/solarsystem/killer_electrons.html wrote:
<<"Killer electrons"?! Should you be hiding under a table?>>
Hello to Neufer and other scientists scared of receiving too many killer electrons,

Electrons from the solar winds that eventually reach the magnetic field around the Earth must go somewhere. Where is that place? Supposely, the electrons should be corralled by the magnetic field lines, circulate along those field line and travel toward one of the Earth's poles. Do all these electrons actually stay suspended above the Earth's atmosphere or collect on the surface of the Earth around one of the polar regions? Does one pole have less electrons than the other?

Electrically challenged,
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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by dougettinger » Fri Oct 26, 2012 1:48 pm

I am still wondering where all the "killer electrons" from the solar eruptions and winds go when they are captured by the magnetic field lines of the Earth's dipole field ? I do not believe they find the Earth's surface in a random fashion and overload man's electronic equipment.

Still electrically challenged,
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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by rstevenson » Fri Oct 26, 2012 2:31 pm

The article neufer linked to says that the electrons can arrive from the Sun, but also that they come up from the Earth. They then dissipate, in ways the article says are being researched.

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by dougettinger » Sat Oct 27, 2012 2:48 pm

Thanks for the reply from "honest Rob". I think what you are saying is that no good theory is available just yet.

May I explore the depths of your mind on this subject ? I believe electrons rotate magnetic field lines of force in a certain direction according to Lenz Law. These electrons not only rotate, but also spiral in a certain direction depending on the magnetic dipole vector. Could one hypothesize then that electrons leave Earth around one polar region and re-enter at the opposite polar region. Any electrons captured from the solar winds follow the magnetic lines of force and also re-enter at this same polar region. Of course, the time for this dissipation to occur in the ionosphere is unknown.

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by rstevenson » Sat Oct 27, 2012 3:41 pm

dougettinger wrote:May I explore the depths of your mind on this subject ?
I believe the proper phrase would be "the shallows" of my mind.

[self-] Honest Rob

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by dougettinger » Sun Oct 28, 2012 8:12 pm

Rob, I was only asking your opinion, your very own idea off the top of your head. You basically know general scientific principles. I wasn't asking that you consult a slew of journals and then exclaim your most educated answer.

Do the electrons captured from the solar winds give Earth a slightly negative charge over the life of the planet ?

"Never appear too serious, otherwise, a wrong answer may indicate stupidity. One could also say he/she is "brainstorming" for fear of looking too stupid."
or
"Gravity guys fear electrons for they heed no reasonable rules."

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by rstevenson » Mon Oct 29, 2012 12:00 am

Okay, but I've only taken first year Physics, so far, therefore I'm on thin ice here. You have been warned.

First problem with expressing the question the way you do: electrons aren't "things" in the usual sense. So the sort of Newtonian thinking that applies to things -- they go this way, they land here -- doesn't apply. You have to think in quantum terms, and that wasn't in my first year courses, except as a very slight intro.

Second... the Sun emits roughly equal amounts of electrons and protons, so there's no reason to think there will be any large imbalance in the charge delivered to the Earth.

In short, the Solar Wind has little effect down here on the surface, and that's a very good thing.

Rob

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by dougettinger » Mon Oct 29, 2012 5:32 pm

Rob, thanks for the warning. I am only a first year Physics person myself. This line of questioning is meant for any experts of the the physics of Earth's outer atmosphere.

Electrons do not move along a conducting wire, but set up vibrations that carry the energy through a conductor. Electrons traveling from the Sun to Earth do not have a medium in which to vibrate or follow. So electrons should be treated like particles including their separated brethren, the proton, within the solar winds. Is this thinking correct? I am not sure where quantum terms enter the picture?

Has there been an experiment conducted to measure the ratio of protons to electrons within the solar wind or an solar eruption?

Do electrons and protons travel to different poles after reaching the Earth's magnetic field lines of force. Or, by the time these particles reach the Earth's atmosphere they lose their ionic characteristics and join each other as discreet atoms ?

Electrically challenged,
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Van Allen Probes: Honoring Origins of Magnetospheric Science

Post by bystander » Sat Nov 10, 2012 3:16 am

The Van Allen Probes: Honoring the Origins of Magnetospheric Science
NASA GSFC | RBSP Van Allen Probes | 2012 Nov 09
Earth's magnetism has captured human attention since the first innovator noticed that a freely moving piece of magnetized iron would always align itself with Earth's poles. Throughout most of history, the origins and physics of this magnetism remained mysterious, though by the 20th century certain things had been learned by measuring the magnetic field at Earth's surface. These measurements suggested that Earth's magnetic field was consistent with that of a giant bar magnet embedded deep inside Earth. However, the magnetic field observed at the surface of our planet is constantly fluctuating. During the 1930s scientists pioneered explanations that such fluctuations were due to streams of particles from the sun striking and becoming entrapped within Earth’s magnetic field.

Truly understanding Earth's magnetic environment, however, required traveling to space. In 1958, the first US rocket -- known as Explorer 1 and led by James Van Allen at the University of Iowa -- was launched. By providing observations of a giant swath of magnetized radiation trapped around Earth, now known as the Van Allen Belts, Explorer 1 confirmed that Earth's magnetic environment, the magnetosphere, was not a simple place. We now know that it has a complex shape – compressed on the side facing the sun, but stretched out into a long tail trailing off away from the sun -- affected as much by incoming material from the sun as Earth's own intrinsic magnetism. This magnetic field constantly fluctuates in response to both internal instabilities and events on the sun. It also provides a home for a host of electrified particles spiraling through this complex system.

A Scientific American article in 1963 said: "Conditions in the magnetosphere are so diverse and so variable . . . that millions of observations by scores of satellites and rocket probes have only begun to plot the broad outlines of this extension of the Earth into space." The age of magnetospheric science had begun, and it hasn't stopped yet. In 2012, those observations continue with the latest addition to NASA's heliospheric fleet: twin satellites launched on Aug. 30, 2012, originally named the Radiation Belt Storm Probes.

On Nov. 9, NASA announced that to honor the scientist who helped launched the field, the probes will be renamed the Van Allen Probes. The renaming comes simultaneously with a standard milestone for any NASA mission: the end of commissioning. Commissioning occurs after launch when all the instruments have been turned on and tested. The end of commissioning also marks the beginning of the prime science mission.

"We are excited to be honoring James Van Allen in this way," says David Sibeck, NASA's mission scientist for the Van Allen Probes at NASA's Goddard Space Flight Center in Greenbelt, Md. "This is an important mission that carries on early magnetospheric work. In the past we have only had one spacecraft at a time looking at the radiation belts. The state-of-the-art instruments we have now are going to be able to comprehensively observe all the types of particles and waves in this part of the magnetosphere."

Indeed, the preliminary data returned from the Van Allen Probes' first two months already has scientists very excited. The instruments all meet or exceed mission specifications and some papers and publications are already planned based on just the first few weeks of observations.

The probes have a planned two-year mission, each with a similar orbit that will carry the spacecraft through all parts of the radiation belts. The basic goal of the mission is to understand what causes the belts to swell and shrink in response to incoming radiation from the sun. Such changes in the belts can endanger satellites in space that orbit near the belts.

To distinguish between a host of theories developed over the years on the radiation belts, Van Allen Probe scientists have designed a suite of instruments to answer three main questions. Where do the extra energy and particles come from? Where do they disappear to, and what sends them on their way? How do these changes affect the rest of the magnetosphere? In addition to its broad range of instruments, the mission will make use of its two spacecraft to better map out the full spatial dimensions of a particular event and how it changes over time.

Scientists want to understand not only the origins of electrified particles – possibly from the solar wind constantly streaming off the sun; possibly from an area of Earth's own outer atmosphere, the ionosphere – but also what mechanisms gives the particles their extreme speed and energy.

"We know examples where a storm of incoming particles from the sun can cause the two belts to swell so much that they merge and appear to form a single belt," says Shri Kanekal, the Van Allen Probes' deputy mission scientist at Goddard. "Then there are other examples where a large storm from the sun didn't affect the belts at all, and even cases where the belts shrank. We need to figure out what causes the differences."

Of course, just like Explorer 1, any new spacecraft will provide unexpected observations that can dramatically change the models and theories about a given region of space. The magnetospheric science that James Van Allen helped initiate will surely provide additional surprises as the Van Allen Probes sweep their way through the radiation belts.

Radiation Belt Mission Renamed to Honor James Van Allen
Universe Today | Nancy Atkinson | 2012 Nov 09
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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by dougettinger » Mon Nov 12, 2012 2:38 pm

Thank you, Bystander. Yes, we will all stand by to receive answers about the Earth's magnetosphere.

Doug
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The Tim Allen Probes

Post by neufer » Mon Nov 12, 2012 2:43 pm

Image
Art Neuendorffer

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Belt RSVP

Post by emc » Mon Nov 12, 2012 6:15 pm

To infinity... and BEYOND!
And if we survive infinity… we’re all heading over to Beyonder Land for a belt :b:.

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Re: Belt RSVP

Post by Beyond » Mon Nov 12, 2012 8:17 pm

emc wrote:
To infinity... and BEYOND!
And if we survive infinity… we’re all heading over to Beyonder Land for a belt :b:.
Memo from Beyonder Land :arrow: BYOB :mrgreen:
To find the Truth, you must go Beyond.

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Re: Belt RSVP

Post by neufer » Mon Nov 12, 2012 11:52 pm

Beyond wrote:
emc wrote:
To infinity...and BEYOND!
And if we survive infinity…
we’re all heading over to Beyonder Land for a belt :b:.
Memo from Beyonder Land :arrow: BYOB :mrgreen:
Art Neuendorffer

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by Beyond » Tue Nov 13, 2012 1:07 am

Hey, datsa pretty good :!: Your creative side must be having a good day today.

Neufer's creative side...
l.jpg
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To find the Truth, you must go Beyond.

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Re: Radiation Belt Storm Probes (RBSP): The Electric Atmosph

Post by emc » Tue Nov 13, 2012 12:35 pm

Stinky Pete huh… maybe we should have our get together outdoors.

Personally, I feel more comfortable in a pastoral setting anyway.