Subscribe free to our newsletters via your
. 24/7 Space News .




EARTH OBSERVATION
Earth Movements From Japan Earthquake Seen From Space
by Staff Writers
Paris, France (ESA) Mar 31, 2011


Envisat Advanced Synthetic Aperture Radar coseismic interferogram from descending track 347, processed by JPL/Caltech ARIA project using ROI_PAC. Data acquired on 19 February and 21 March 2011, spanning the main shock of the magnitude 9 earthquake and the magnitude 7.9 aftershock that occurred in Japan on 11 March 2011. One colour cycle represents 50 cm of motion in the radar line of sight (approximately west at 41 degrees from the vertical). The seismicity plot is from the US Geological Survey. (The red star denotes the quake's epicentre, and the yellow circles represent aftershocks). Credits: Based on ESA data - JPL/Caltech ARIA project (E. Fielding, Principal Scientist JPL/Caltech; S. Yun, Research Scientist JPL/Caltech; P. Agram, KISS Postdoctoral Fellow Caltech)

Satellite images have been essential for helping relief efforts in Japan following the massive quake that struck on 11 March. Now scientists are using ESA's space radars to improve our understanding of tectonic events.

Scientists are calling on data from the advanced radar on ESA's Envisat satellite to map surface deformations caused by the magnitude-9 earthquake. Studying data acquired on 19 February and 21 March, scientists from NASA's Jet Propulsion Laboratory have detected a ground shift of about 2.5 m eastwards and a downward motion of Honshu Island's east coast.

Scientists from Italy's Istituto Nazionale di Geofisica e Vulcanologia have used the same Envisat data to show a large portion of the surface displacement, with a maximum shift of 2.5 m.

These first results, covering an 800 km-long strip over Sendai and Tokyo, show movement far away from the epicentre (denoted by the red star in the top image) in the Pacific Ocean.

The complex technique being used by the scientists is known as 'InSAR' - synthetic aperture radar interferometry. It combines before and after radar images of the same ground location from the same position in space in such a way as to detect ground motion down to a few millimetres.

These analyses could only be made now because Envisat's orbit repeats every 30 days. After capturing the area on 19 February -before the earthquake - Envisat's repeat scan from the same position in space came on 21 March. Envisat is still making repeat visits to cover the full area.

Another veteran ESA satellite is also contributing to the Japan radar coverage. After 16 productive years, ERS-2 will end its mission this year, but its repeat cycle was fortuitously changed earlier this month from 35 days to 3 days to collect innovative radar information.

Its three-day repetition is providing partial coverage over Japan, north of Sendai. Collection of ERS-2 radar data over this area began after the main earthquake with the aim of mapping the aftershocks. Scientists are now working on these data.

This disaster marks the first time that multiple space agencies - ESA, the German Aerospace Center and the Japan Aerospace Exploration Agency - are openly providing SAR data for understanding tectonic processes under the GeoHazard Supersites initiative, coordinated by the Group on Earth Observations.

The initiative is stimulating international efforts and fostering collaboration between space agencies, in-situ data providers and users to further our understanding of geological risks.

The initiative provides scientists with access to in-situ and spaceborne data, including 20 years of satellite radar observations.

This joint collaboration, incorporating all available space and ground data, is an efficient way to make significant progress in assessing the area's future vulnerability while reconstruction is under way.

.


Related Links
GeoHazard Supersites
Earth Observation News - Suppiliers, Technology and Application






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








EARTH OBSERVATION
NASA Satellites Detect Extensive Drought Impact On Amazon
Boston MA (SPX) Mar 30, 2011
A new NASA-funded study has revealed widespread reductions in the greenness of the forests in the vast Amazon basin in South America caused by the record-breaking drought of 2010. "The greenness levels of Amazonian vegetation - a measure of its health - decreased dramatically over an area more than three and one-half times the size of Texas and did not recover to normal levels, even after ... read more


EARTH OBSERVATION
84 Teams To Compete In NASA Great Moonbuggy Race

A New View Of Moon

Super Full Moon

LRO Delivers Treasure Trove Of Data

EARTH OBSERVATION
Study Of 'Ruiz Garcia' Rock Completed

Next Mars Rover Gets A Test Taste Of Mars Conditions

Alternatives Have Begun In Bid To Hear From Spirit

Opportunity Completes Study Of Ruiz Garcia Rock

EARTH OBSERVATION
China set to outstrip US in science research output

NASA Makes Selection For Integrated Communications Services

NASA computer servers vulnerable to attack: audit

Beginning Of Era Of Manned Spaceflight

EARTH OBSERVATION
What Future for Chang'e-2

China setting up new rocket production base

China's Tiangong-1 To Be Launched By Modified Long March II-F Rocket

China Expects To Launch Fifth Lunar Probe Chang'e-5 In 2017

EARTH OBSERVATION
Russia To Launch Space Freighter To ISS On April 27

Japan's HTV-2 Cargo Spaceship Undocks From ISS

Data Streaming In From Space Station To OSU Lab

Unique Aerospace Invention Ready For Debut

EARTH OBSERVATION
Final Countdown Is Underway For Second Ariane 5 Flight Of 2011

Next Ariane 5 Mission Ready For March 30 Liftoff

Another Ariane 5 Completes Its Initial Build-Up At The Spaceport

Two Ariane 5 And One Soyuz Flights Are Now Being Prepared

EARTH OBSERVATION
White Dwarfs Could Be Fertile Ground For Other Earths

NASA Announces 2011 Carl Sagan Fellows

Report Identifies Priorities For Planetary Science 2013-2022

Planetary Society Statement On Planetary Science Decadal Survey For 2013-2022

EARTH OBSERVATION
3-D system guides helicopter brownout

MSUA Honors KVH For Innovation In Satellite Communication

Black box for spacecraft tested

Cancer Risk Of Backscatter Airport Scanners Is Low




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