Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




MERCURY RISING
Mercury's Magnetic Field Measured by MESSENGER Orbiter
by Staff Writers
Laurel MD (SPX) May 18, 2012


File image.

Researchers working with NASA's Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) spacecraft report the frequent detections of Kelvin-Helmholtz (KH) waves at the edge of the innermost planet's magnetosphere.

In six different sets of magnetic field measurements made by the orbiter as it passed through Mercury's magnetopause, the boundary that separates the planet's magnetosphere from the solar wind plasma in the magnetosheath, Sundberg et al. detect the magnetic field oscillations characteristic of fully developed KH waves.

Kelvin-Helmholtz waves form when fluids of different speeds travel alongside each other - in this case, the magnetosphere and magnetosheath plasmas - and promote mixing of the plasmas on larger spatial scales, and shorter time scales, than diffusive transport. The observations, which span the first 88 days of MESSENGER's time in orbit, bring Mercury alongside Earth, Saturn, and Venus as planets for which such Kelvin-Helmholtz waves are of importance.

The waves seen at Mercury's magnetopause, however, differ markedly from those at Earth's. The authors' KH wave observations were all made in the postnoon and duskside region of Mercury's magnetosphere, whereas at Earth, KH waves are seen farther toward the nightside on both flanks.

Moreover, the measured waves had periods averaging 10-20 seconds, whereas the periods of their terrestrial counterparts are several minutes.

Also, the amplitudes of the measured magnetic field oscillations were 2-3 times larger than those seen at Earth. Wave growth at the magnetopause is known to be an important mechanism for transporting material across the largely impermeable boundary, and the authors propose that these newly identified Kelvin-Helmholtz waves could be the source of plasma for Mercury's dayside boundary layer, discovered previously by the MESSENGER mission.

Torbjorn Sundberg: Heliophysics Science Division, NASA Goddard Space Flight Center, Maryland, USA; Scott A. Boardsen: Heliophysics Science Division, NASA Goddard Space Flight Center, Maryland, USA and Goddard Earth Sciences and Technology Center, University of Maryland, Maryland, USA; James A. Slavin, Thomas H. Zurbuchen, and Jim M. Raines: Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Michigan, USA; Brian J. Anderson and Haje Korth: The Johns Hopkins University Applied Physics Laboratory, Maryland, USA; Sean C. Solomon: Department of Terrestrial Magnetism, Carnegie Institution of Washington, District of Columbia, USA. "MESSENGER orbital observations of large-amplitude Kelvin-Helmholtz waves at Mercury's magnetopause" Journal of Geophysical Research-Space Physics, doi:10.1029/2011JA017268, 2012.

.


Related Links
MESSENGER at APL
News Flash at Mercury
Mars News and Information at MarsDaily.com
Lunar Dreams and more






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





MERCURY RISING
Messenger Gains Deputy Principal Investigator
Laurel MD (SPX) May 11, 2012
Larry Nittler, a staff scientist in the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, has been named deputy principal investigator of the Messenger mission. Messenger Principal Investigator Sean Solomon, of CIW, delivered the announcement this morning at the first plenary of the 26th meeting of the Messenger Science Team meeting in Vancouver, B.C. Solomon, ... read more


MERCURY RISING
Perigee "Super Moon" On May 5-6

India's second moon mission Chandrayaan-2 to wait

European Google Lunar X Prize Teams Call For Science Payloads

Russia to Send Manned Mission to Moon by 2030

MERCURY RISING
To the Highlands of Mars

Opportunity Rolling Again After Fifth Mars Winter

Mojave Desert Tests Prepare for NASA Mars Roving

Mars Opportunity Rover Is A Go For More Travel

MERCURY RISING
SpaceX Falcon 9 Dragon Launch Aborted

NASA chooses rocket for Orion launches

World expert outlines the future for air space travel

Poland seeks competitive edge through new technology

MERCURY RISING
When Will Shenzhou 9 Be Launched

China's space women wait for blast-off

Shenzhou 9 to be ready for mid-June launch?

China confirms plans to build own orbital station

MERCURY RISING
Space Station - Here We Come!

ISS Research and Development Conference June 26-28 Denver

ISS Cosmonauts to Make 3D Photo Report

Russia delivers three astronauts to ISS: official

MERCURY RISING
SpaceX scrubs launch to ISS over rocket engine problem

SpaceX readies ambitious ISS launch

Japan in first commercial satellite launch

The numbers add up in Arianespace's latest commercial launch success with Ariane 5

MERCURY RISING
Newfound exoplanet may turn to dust

Cosmic dust rings no guarantee of planets

In search of new 'Earths' beyond our Solar System

Free-floating planets in the Milky Way outnumber stars by factors of thousands

MERCURY RISING
Loral-Built Nimiq 6 Satellite ly Performs Post-Launch Maneuvers

China firm buys AMC to create cinema giant

At seventh birthday, YouTube marks new milestones

SciTechTalk: Google to reign in Android




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal 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