Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. 24/7 Space News .




SOLAR SCIENCE
THEMIS Discovers New Process that Protects Earth from Space Weather
by Karen C. Fox for Goddard Space Flight Center
Greenbelt MD (SPX) Mar 11, 2014


NASA's THEMIS mission observed how dense particles normally near Earth in a layer of the uppermost atmosphere called the plasmasphere can send a plume up through space to help protect against incoming solar particles during certain space weather events. Image courtesy NASA/Goddard Space Flight Center. To view a GIF of the process please go here.

In the giant system that connects Earth to the sun, one key event happens over and over: solar material streams toward Earth and the giant magnetic bubble around Earth, the magnetosphere helps keep it at bay. The parameters, however, change: The particles streaming in could be from the constant solar wind, or perhaps from a giant cloud erupting off the sun called a coronal mass ejection, or CME.

Sometimes the configuration is such that the magnetosphere blocks almost all the material, other times the connection is long and strong, allowing much material in. Understanding just what circumstances lead to what results is a key part of protecting our orbiting spacecraft from the effects of such space weather.

Now, for the first time, a study shows that in certain circumstances a pool of dense particles normally circling Earth, deep inside the magnetosphere, can extend a long arm out to meet - and help block - incoming solar material.

"It's like what you might do if a monster tried to break into your house. You'd stack furniture up against the front door, and that's close to what the Earth is doing here," said Brian Walsh, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.

"The material that is usually much nearer Earth stacks up against the outer boundary of the magnetosphere, throttling the interaction there and stopping solar material from entering."

In the March 6, 2014, issue of Science Express, Walsh and his colleagues compared observations from the ground and in space during a solar storm on Jan. 17, 2013. This was a fairly moderate solar storm caused by a CME impacting Earth's magnetosphere for several hours.

As the CME encountered the boundary of the magnetosphere, its magnetic fields and those around Earth realigned in a process called magnetic reconnection, which allowed energy and solar material to cross the boundary into the magnetosphere.

NASA's three THEMIS - for Time History of Events and Macroscale Interactions during Substorms - spacecraft were in the right place at the right time, flying through the magnetosphere's boundary approximately 45 minutes apart, and caught this interaction.

Closer to Earth, scientists could also study the sphere of cold dense gas at the very top of our atmosphere. This region is called the plasmasphere and it's made of what's known as plasma, a gas made of charged particles. GPS signals travel through the plasmasphere and they travel at different speeds depending on how thick or thin the plasmasphere is along the journey. Tracking the GPS radio signals, therefore, can help researchers map out the properties of the plasmasphere.

"A colleague who works with these kind of observations said I had to see some interesting data showing a plume from the ground," said Walsh. "And I typed in the dates and saw that it was a date when THEMIS was in the right position. So, for the first time, we could make a comparison."

THEMIS showed that the tongue of this cold, dense plasmasphere material stretched all the way up to the magnetic reconnection point where the CME had made contact with the magnetopause. The three sets of THEMIS observations demonstrated that the plume had a dramatic impact on the characteristics of the magnetic reconnection region.

"It wouldn't work if the magnetic reconnection happened for only a few minutes," said David Sibeck the project scientist for THEMIS at NASA Goddard. "But if it lasts long enough, the whole magnetosphere gets involved. This tongue of the plasmasphere surges out, adding another layer of protection, curbing the magnetic reconnection."

As scientists try to better understand the space weather system around Earth, they rely on multipoint observations such as this to connect what's seen on the ground to what's seen in space. In this case THEMIS data connected to GPS data, but such combinations are increasingly being used to watch how Earth is affected by its closest star.

Eventually such observations could lead to improvements in space weather predictions, which would be as useful for spacecraft operators as terrestrial weather forecasts are for us here on Earth.

.


Related Links
Themis at NASA
Solar Science News at SpaceDaily






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





SOLAR SCIENCE
Plasma plumes help shield Earth from damaging solar storms
Boston MA (SPX) Mar 10, 2014
The Earth's magnetic field, or magnetosphere, stretches from the planet's core out into space, where it meets the solar wind, a stream of charged particles emitted by the sun. For the most part, the magnetosphere acts as a shield to protect the Earth from this high-energy solar activity. But when this field comes into contact with the sun's magnetic field - a process called "magnetic recon ... read more


SOLAR SCIENCE
Russia to launch three lunar rovers from 2016 to 2019

Control circuit malfunction troubles China's Yutu

China's Lunar Lander Still Operational

China Focus: Uneasy rest begins for China's troubled Yutu rover

SOLAR SCIENCE
India's Mars mission to reach Red Planet in 200 days

Opportunity Mars Rover Exploring Murray Ridge Area

Mars Rover Oppportunity Crushing Rocks With Wheels

Relay Radio on Mars-Bound NASA Craft Passes Checkout

SOLAR SCIENCE
Bright pulses of light could make space veggies more nutritious

Mini Rocket Models to be Used in a Big Way for SLS Base Heating Test

Under shadow of spy scandal, Merkel, Cameron head to tech fair

Committee Democrats Emphasize Need for Human Space Exploration Roadmap

SOLAR SCIENCE
China to launch first "space shuttle bus" this year

Feature: The "masters" behind China's lunar rover Jade Rabbit

China expects to launch cargo ship into space around 2016

China capable of exploring Mars

SOLAR SCIENCE
Japanese astronaut becomes ISS commander

American, two Russians back on Earth after half-year in space

Station Crew Preps for Return to Earth, Repairs Recycling System

NASA says US-Russia space ties 'normal'

SOLAR SCIENCE
Payload prep continues for Arianespace Soyuz for Sentinel-1A

Russia to Start Building New Manned Rocket Launch Pad in 2015

New Vostochny space center a key priority for Russian Far East

'Mission of Firsts' Showcased New Range-Safety Technology at NASA Wallops

SOLAR SCIENCE
Every red dwarf star has at least one planet

Galactic gas caused by colliding comets suggests mystery 'shepherd' exoplanet

'Dimer molecules' aid study of exoplanet pressure, hunt for life

A small step toward discovering habitable earths

SOLAR SCIENCE
South Africa's nano-satellite encounters space debris

First step towards programmable materials

Australia to prevent 'Gravity' space crash with lasers

Aerojet Rocketdyne Provides Propulsion For GPM Satellite




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.