In a background magnetic field, represented by the cyan arrows, two electrons are propagating to the right, executing identical gyromotion. A circularly polarized electromagnetic wave approaches the upper electron from the left.
Encircling Earth are two enormous rings — called the Van Allen radiation belts — of highly energized ions and electrons. Various processes can accelerate these particles to relativistic speeds, which endanger spacecraft unlucky enough to enter these giant bands of damaging radiation. Scientists had previously identified certain factors that might cause particles in the belts to become highly energized, but they had not known which cause dominates.
Now, with new research from NASA’s Van Allen Probes and Time History of Events and Macroscale Interactions during Substorms — THEMIS — missions, published in Geophysical Research Letters, the verdict is in. The main culprit is a process known as local acceleration, caused by electromagnetic waves called chorus waves. Named after their characteristic rising tones, reminiscent of chirping birds, chorus waves speed up the particles pushing them along like a steady hand repeatedly pushing a swing. This process wasn’t a widely accepted theory before the Van Allen Probes mission.
Establishing the main cause of the radiation belt enhancements provides key information for models that forecast space weather — and thus protect our technology in space.
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As we develop more and more powerful tools to peer beyond our solar system, we learn more about the seemingly endless sea of faraway stars and their curious casts of orbiting planets. But there’s only one star we can travel to directly and observe up close — and that’s our own: the Sun.
Two upcoming missions will soon take us closer to the Sun than we’ve ever been before, providing our best chance yet at uncovering the complexities of solar activity in our own solar system and shedding light on the very nature of space and stars throughout the universe.
Together, NASA’s Parker Solar Probe and ESA’s (the European Space Agency) Solar Orbiter may resolve decades-old questions about the inner workings of our nearest star. Their comprehensive, up-close study of the Sun has important implications for how we live and explore: Energy from the Sun powers life on Earth, but it also triggers space weather events that can pose hazard to technology we increasingly depend upon. Such space weather can disrupt radio communications, affect satellites and human spaceflight, and — at its worst — interfere with power grids. A better understanding of the fundamental processes at the Sun driving these events could improve predictions of when they’ll occur and how their effects may be felt on Earth.
“Our goal is to understand how the Sun works and how it affects the space environment to the point of predictability,” said Chris St. Cyr, Solar Orbiter project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This is really a curiosity-driven science.”
Parker Solar Probe is slated to launch in the summer of 2018, and Solar Orbiter is scheduled to follow in 2020. These missions were developed independently, but their coordinated science objectives are no coincidence: Parker Solar Probe and Solar Orbiter are natural teammates.
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#MAVEN measurements of a series of solar flares that erupted in September 2017 provided the first in situ data of #Mars’ upper atmospheric response to such an event.
Data from MAVEN’s suite of instruments revealed increased interactions between Mars’ ionosphere and thermosphere, and significantly higher than average O₂ atmospheric escape rates.
Read a related story in the American Geophysical Union (AGU)‘s EOS publication: http://bit.ly/2JfYbKJ.
To read the original related paper in Geophysical Research Letters, please visit: https://agupubs.onlinelibrary.wiley.com….
Laboratory for Atmospheric and Space Physics
University of Colorado Boulder
(Video credit: NASA Goddard)
We are rolling in Vandenberg Air Force Base as our crew completed all-day operations to move and mate the #Pegasus rocket to the #Stargazer #L1011 airplane in preparation for the June 14 launch of #NASAICON. Developed, integrated and tested by our teams in Dulles, VA and Gilbert, AZ, ICON will be the newest addition to NASA’s Heliophysics missions. Led by UC Berkeley, the mission will help scientists better understand the relationship between Earth’s atmosphere and the space environment by studying the ionosphere. Next week, the unique air-launch vehicle will make the ferry flight to its Kwajalein Atoll launch site in the Marshall Islands. Stay tuned to NASA’s Launch Services Program for live launch coverage!
Magnetic reconnection, one of the most important processes in the plasma-filled space around Earth, dissipates magnetic energy and propels charged particles, both of which contribute to a dynamic space weather system that scientists want to understand and someday predict. (NASA’s Goddard Space Flight Center/Joy Ng video)
The discovery will help scientists understand the role magnetic reconnection plays elsewhere in space, for example, in heating the inexplicably hot solar corona — the sun’s outer atmosphere — and accelerating the supersonic solar wind. NASA’s upcoming Parker Solar Probe mission will be launched directly toward the sun this summer to investigate exactly those phenomena, armed with this new understanding of magnetic reconnection near Earth.
And since magnetic reconnection occurs throughout the universe, what scientists learn about it around our planet — which is easier to examine — can be applied to other processes farther away.
“MMS discovered electron magnetic reconnection, a new process much different from the standard magnetic reconnection that happens in calmer areas around Earth,” said Tai Phan, a senior fellow in the Space Sciences Laboratory at the University of California, Berkeley. “This finding helps scientists understand how turbulent magnetic fields dissipate energy throughout the cosmos.”
Phan is lead author of a paper describing the findings that will be published this week in the journal Nature.
The complete article
Significant Space Weather Impact on the Escape of Hydrogen from Mars
Newly published MAVEN results indicate that atmospheric escape of hydrogen during a strong solar storm that impacted Mars in September 2017 was comparable to the seasonal escape of hydrogen over a full #Martian year.
Read the full publication in American Geophysical Union (AGU)‘s Geophysical Research Letters: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018GL077727.
Center for Space Physics at Boston University
UC Berkeley Space Sciences Lab
May 11th 2009, the Space Shuttle Atlantis, lifted off from Pad 39A at the Kennedy Space Center on Mission STS-125, the last Hubble Servicing Mission. On board were a variety of new instruments, Wide Field Camera 3, A Soft Capture Mechanism, New Gyroscopes, Batteries, a Science and Data Handling Unit and COS – Cosmic Origins Spectrograph, pictured below.
COS Lifted into Orbiter Transport Carrier. Photo Courtesy of NASA
The microchannel plate detector and associated electronics (low and high voltage power supplies, amplifiers, time to digital converters, and control and processing board) for the far ultraviolet (FUV) channel of COS were built by the Experimental Astrophysics Group at UC Berkeley Space Sciences Lab for Principal Investigator Dr. James Green of the Center for Astrophysics and Space Astronomy at the University of Colorado Boulder.
The servicing mission was intended to extend the life of the Hubble Space Telescope an additional 5 years. All instruments are still working nominally 9 years post launch.
STS 125 Leaving the Vertical Assembly Building on its way to Pad 39A: Courtesy Christopher Scholz
Launch of STS 125 from Pad 39A on it way up to capture the Hubble Space Telescope: Courtesy Christopher Scholz