Micro-scale current sheets unleash macro-scale space weather

Asia's Tech News Daily

Micro-scale current sheets unleash macro-scale space weather

While movies show Earth as existing in a calm, pristine corner of the universe, in reality the near-Earth space environment is dangerous and dynamic. On any given day, hot charged particles and blobs of plasma, called the solar wind, travel from the sun and are deflected by the Earth’s magnetic field, causing beautiful aurora around north and south poles.

During solar storms, however, the solar wind can compress the Earth’s magnetic field, causing the magnetic field lines to rearrange and reconnect (also known as magnetic reconnection), shooting hot, dense plasma back toward the Earth.

Processes like these are commonly referred to as space weather. Because of the effect that these space-based disruptions can have on key elements of our modern society, such as telecommunication systems and power grids, obtaining a good understanding of these processes is just as essential as understanding ground-based weather.

A major challenge in understanding magnetic reconnection in the Earth’s magnetosphere has been the difficulty in resolving the smaller kinetic-scale processes in satellite observations. NASA’s Magnetospheric Multi-Scale (MMS) spacecraft, however, recently made it possible to make detailed studies of this previously unseen micro-scale physics.

Scientists at the U.S. Naval Research Laboratory (NRL) in Washington, D.C. have been using MMS data to study the micro-scale physics that occurs in the Earth’s magnetotail, a thin portion of the magnetosphere that is illustrated in Figure 1. The magnetotail is formed when the Earth’s magnetosphere is compressed by the solar wind into a thin current sheet, creating an ideal location to study magnetic reconnection.

NRL scientists recently made the first observation of plasma waves driven by highly sheared electron flows (velocity shear) in one of these compressed current sheets. The velocity shear is created in the current sheet when a localized electric field oriented perpendicular to the background magnetic field arises as the current sheet is compressed. These waves are a rich source of local enhanced diffusivities, which can trigger the magnetic reconnection process.

NRL scientists also used these observations to discover a key component missing from existing theoretical models of thin current sheets and magnetic reconnection-an ambipolar electric field that forms perpendicular to the current sheet and intensifies as the current sheet undergoes strong compression. A new theoretical model has since been developed and indicates that the ambipolar electric field can self-consistently develop in response to global compression of the plasma.

This in turn produces the velocity shear that can drive the waves observed in the spacecraft data. The current driven by the electron flow also changes the magnetic field profiles and allows for the formation of current sheets that are both thin and non-ideal, features which cannot simultaneously be explained by the standard models. The theoretical model results shine a new light on the key connection between the micro-scale and macro-scale physics.

These findings challenge the existing understanding of the physics of thin current sheets, and the identification of the shear-driven plasma waves also establishes the significance of the localized ambipolar electric field and the highly inhomogeneous conditions that drive the physics.

This deeper understanding of the physics at small scales, when combined with the larger scale models, will lead to a more complete knowledge of the global dynamics and especially the energy flux in the heliosphere from the sun into the Earth’s immediate neighborhood that affects near-Earth space weather.

Internet Explorer Channel Network
Asia's Tech News Daily
News Related

OTHER NEWS

NASA awards contract for bed rest studies

NASA has selected Deutsches Zentrum fur Luft-und Raumfahrt (DLR) of Cologne, Germany, to provide use of its facility to support long-duration bed rest research. The $49.9 million Bedrest Studies Contract ... Read more »

Magellanic Stream arcing over Milky Way may be five times closer than previously thought

Our galaxy is not alone. Swirling around the Milky Way are several smaller, dwarf galaxies – the biggest of which are the Small and Large Magellanic Clouds, visible in the ... Read more »

Research in Brief: First-ever interior Earth mineral discovered in nature

UNLV geochemists have discovered a new mineral on the surface of the Earth. There’s just one catch: it shouldn’t be here. The mineral – entrapped in a diamond – traveled ... Read more »

Crew operations aboard Space Station return to normal

NASA and U.S. Space Command continue to monitor the debris cloud created by a recent Russian anti-satellite test. The International Space Station and crew members are safe and have resumed ... Read more »

Aerospike engine from Pangea Aerospace trialled on DLR test stand

Unique test stands, comprehensive expertise and decades of experience – the Lampoldshausen site of the German Aerospace Center (Deutsches Zentrum fur Luft- und Raumfahrt; DLR) specialises in developing and testing ... Read more »

Solar Orbiter returns to Earth before starting its main science mission

Solar Orbiter is returning to Earth for a flyby before starting its main science mission to explore the Sun and its connection to ‘space weather’. During the flyby Solar Orbiter ... Read more »

Maritime Launch Services announces Nanoracks as payload provider; Unveils Spaceport Nova Scotia design

Maritime Launch Services, one of Canada’s leading aerospace firms and the owner of the country’s first commercial spaceport, announced that Nanoracks, a Voyager Space company and the leading commercial payload ... Read more »

Satellite operator Telesat goes public

Telesat Corporation announced today that it is now a public company and will begin trading on the Nasdaq Global Select Market and the Toronto Stock Exchange under the ticker symbol ... Read more »

China launches new satellite

China launched a new satellite from the Taiyuan Satellite Launch Center in the northern province of Shanxi on Saturday. The satellite, Gaofen-11 03, was launched by a Long March-4B rocket ... Read more »

Stanford researchers are using AI to create better VR experiences

Virtual and augmented reality headsets are designed to place wearers directly into other environments, worlds and experiences. While the technology is already popular among consumers for its immersive quality, there ... Read more »

Bezos' Blue Origin hires lobbyist after 'Space Tax' proposed

This year, the company spent over $1.3 million on lobbying, in addition to $2 million in 2020. Jeff Bezos’ Blue Origin hired Mac Campbell from Capitol Counsel – a lobbyist ... Read more »

Decisions from the ESA Intermediate Ministerial Meeting 2021

Government ministers in charge of space activities in ESA’s Member States today met at an Intermediate Ministerial Meeting held in Matosinhos, Portugal. The Council of Ministers unanimously adopted a Resolution ... Read more »

Turning space junk into rocket fuel

While SpaceX is working hard to make reusable rockets a new reality, the launches still leave behind massive amounts of debris in orbit, posing a potential hazard to communication satellites ... Read more »

BlackSky set to expand its EO constellation for real-time global intelligence

BlackSky’s latest satellites reached orbit and delivered first insights within 14 hours of launch. The company’s constellation growth signals a return to space and an increased capacity for global customers. ... Read more »

Japanese space tourists arrive at launch site ahead of ISS trip

Japanese billionaire Yusaku Maezawa arrived at the Baikonur cosmodrome in Kazakhstan on Friday for training ahead of his flight to the International Space Station on a Russian-operated spacecraft. Maezawa’s mission ... Read more »

Bacteria may be key to sustainably extracting earth elements for tech

Rare earth elements from ore are vital for modern life but refining them after mining is costly, harms the environment and mostly occurs abroad. A new study describes a proof ... Read more »

ESA selects revolutionary Venus EnVision mission

EnVision will be ESA’s next Venus orbiter, providing a holistic view of the planet from its inner core to upper atmosphere to determine how and why Venus and Earth evolved ... Read more »

Meet VMS - the briefcase-sized chemistry lab headed to Venus

Short for Venus Mass Spectrometer, VMS is one of five instruments aboard the DAVINCI descent probe. Launching in 2029, DAVINCI will be the first US probe mission to enter Venus’ ... Read more »

Scientists eagerly await James Webb telescope to discover stars, exoplanets

Scientists around the world eagerly await discoveries of early galaxies and exoplanets after the James Webb Space Telescope, the most powerful telescope ever conceived, is launched Dec. 18, a panel ... Read more »

US still characterizing damage of satellite struck in Russian missile test

The United States is still characterising the damage from an anti-satellite missile test allegedly conducted by Russia earlier this week, US Space Command Deputy Commander John Shaw said on Wednesday. ... Read more »

SES orders 2 new sats for Prime TV Neighbourhood serving 118 million homes

SES has ordered two geostationary (GEO) Ku-band satellites for its prime orbital slot at 19.2 degrees East to maintain the premium services it provides to its European video customers and ... Read more »

When debris disaster strikes

In 2021 so far, some 2467 new objects large enough to be tracked have been added to world catalogues of orbital objects, out of which 1493 are new satellites and ... Read more »

Astronomical object found by amateur identified as new dwarf galaxy

Enthusiast Giuseppe Donatiello spotted the galaxy while scrutinising publicly available data and his finding was investigated by professional astrophysicists, led by Dr. David Martinez-Delgado from the Instituto de Astrofisica de ... Read more »

Hubble Takes a Grand Tour of the Solar System

The NASA/ESA Hubble Space Telescope has completed its annual grand tour of the outer Solar System. This is the realm of the giant planets – Jupiter, Saturn, Uranus, and Neptune ... Read more »

Teledyne e2v HiRel offers new radiation dosimeters for space applications

Teledyne e2v HiRel has announced availability of 3 new radiation dosimeter models that further broaden its popular range of radiation measurement devices. Aimed at high altitude aerospace applications and all ... Read more »

Planetary defenders: after NASA's DART comes ESA's Hera

The world will be watching the milestone launch of NASA’s Double Asteroid Redirection Test, DART, spacecraft on Wednesday, 24 November, intended to alter one small part of the Solar System ... Read more »

RocketStar gets SBIR contract to develop new plasma thrusters

RocketStar, an industry leader transforming access to space with fully reusable rockets, has announced that the company has been selected by the U.S Air Force to participate in a Small ... Read more »

CGI selected for GSA's ASTRO space and development IDIQ contract

CGI has been selected by the General Services Administration (GSA) for the multi-award ASTRO Indefinite-Delivery/Indefinite-Quantity (IDIQ) contract. This 10-year award provides CGI the opportunity to compete for task orders with ... Read more »

First all-private space station mission to include two dozen experiments

A private space company that’s planning to send the first all-private crew to the International Space Station announced on Wednesday that they will conduct medical and scientific experiments during their ... Read more »

Arianespace to launch Australian satellite Optus-11 with Ariane 6

Arianespace and Australian operator SingTel Optus signed the launch contract for the Optus-11 communications satellite. The launch, scheduled for the second half of 2023, will use the Ariane 64 version ... Read more »

Rocket Lab launches 107th satellite; Tests helicopter recovery operations

Rocket Lab has successfully deployed two satellites to orbit for real-time geospatial monitoring company BlackSky. Rocket Lab also successfully introduced helicopter operations to a recovery mission for the first time, ... Read more »

Latest Vega launch paves way for Vega-C

Arianespace announced liftoff of Vega’s twentieth flight from Europe’s Spaceport in French Guiana at 9:27 GMT (10:27 CET; 06:27 local time). Vega delivered three CERES payloads for the French Ministry ... Read more »

Pangea Aerospace hot fire tests the first MethaLox aerospike engine in the world

Pangea Aerospace, a company from Barcelona (Spain), has fired several times the first MethaLox aerospike engine in the world in their first try, at DLR Lampoldshausen facilities. The company has ... Read more »

PLD Space exhibits the first privately-developed Spanish rocket

PLD Space has achieved a new milestone with the official presentation in Madrid of its MIURA 1 rocket, that has been exhibited fully assembled for the first time in the ... Read more »

LeoLabs Australia's Space Tracking Centre releases first images of Russian space debris field

As reported, the Russian Federation tested a probable ‘Nudol’ direct ascent anti-satellite missile yesterday at 150250Z from Pllesetk, Russia with the target a defunct Russian satellite called Cosmos 1408. The ... Read more »

The worlds next door: Looking for habitable planets around Alpha Centauri

A mission to discover new planets potentially capable of sustaining life around Earth’s nearest neighbor, Alpha Centauri, was announced this week by Sydney University. The proposed telescope project will look ... Read more »

"Alien" invasions and the need for planetary biosecurity

The era of space exploration brings with it a new risk: invasion. The peril comes not from little green men arriving on flying saucers but, rather, from microbiological contamination of ... Read more »

Research casts new light on processes behind solar eruptions

Their work could provide a key piece to help solve a puzzle which solar astronomers have been aiming to solve for decades – what is the origin of magnetic twist ... Read more »

Alien organisms - hitchhikers of the galaxy

Scientists warn, without good biosecurity measures ‘alien organisms’ on Earth may become a reality stranger than fiction. Published in international journal BioSciences, a team of scientists, including Dr Phill Cassey, ... Read more »

NASA's next steps to return Hubble to normal operation status

The Hubble Space Telescope’s Advanced Camera for Surveys has continued collecting science data as NASA works to address the anomaly that started Oct 25. Missed synchronization messages halted science production ... Read more »
On free-english-test.com you will find lots of free English exam practice materials to help you improve your English skills: grammar, listening, reading, writing, ielts, toeic