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




ICE WORLD
CryoSat rocking and rolling
by Staff Writers
Paris (ESA) Oct 19, 2011


CryoSat is dedicated to monitoring changes in the thickness of marine ice floating in the polar oceans and of the vast ice sheets that extend over Greenland and the Antarctic.

ESA's ice satellite is rolling left and right in orbit to help it continue its precise measurements of the vast ice sheets that blanket Greenland and Antarctica. Since its launch 18 months ago, CryoSat-2 has been collecting data to improve our understanding of the relationship between ice and climate. Just this year, the first map of Arctic sea-ice thickness was unveiled, and the satellite will continue to monitor the changing ice for years to come.

To ensure the precision of the measurements, an operation is under way to roll the satellite from side to side as it flies over the flat oceans.

This manoeuvre is to calibrate CryoSat's radar altimeter for measuring ice thickness, especially over the margins of ice sheets.

The altimeter has two antennas mounted on a bench about a metre apart. When it is working in the 'SARIn' mode, both antennas are used in parallel: one emits a signal and both receive the signals that bounce back.

Normally, this bench is parallel to Earth's surface. But at the edges of the ice sheets, the ice surface is not always flat and the slopes affect the return signals.

Harsh conditions in space - with huge temperature differences between Sun and shade - can lead to the deterioration of CryoSat's instruments, which can also lead to measurement errors.

In order to quantify these errors, ESA ground controllers are working to recalibrate the altimeter.

They are rolling the satellite to simulate the ice slopes and holding it in this position for several minutes. This must be done while CryoSat is over large, flat surfaces. For satellite altimeters, oceans are Earth's largest flat surfaces.

It will also check whether errors are related to CryoSat's varying thermal conditions - like when exposed to the Sun or in the shade.

"With the results from the different sets of rolls over different ocean surfaces and at different ambient conditions, we are aiming to characterise the instrument to a precision better than we thought we could make at the time of the launch," said Tommaso Parrinello, CryoSat mission manager.

During several manoeuvres on Monday and Tuesday, the satellite is rolling 0.4 degrees to both sides while over the Indian and Pacific oceans, before returning to its original position.

"The preparations for the roll activities have been quite challenging," explained Nic Mardle, spacecraft operations manager.

"Although we had experience of these activities from the commissioning phase, we had to iterate a few more times with the planning and mission control teams so that we could support exactly what was required."

The complex calibration is a joint effort between ESA's ESRIN centre for Earth observation in Italy and its ESOC operations centre in Germany.

CryoSat is dedicated to monitoring changes in the thickness of marine ice floating in the polar oceans and of the vast ice sheets that extend over Greenland and the Antarctic.

Satellites have already shown that the extent of sea ice in the Arctic is diminishing. In fact, this year's minimum has set a new record low.

.


Related Links
CryoSat
Beyond the Ice Age






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





ICE WORLD
US probes mystery disease killing Arctic seals
Washington Oct 14, 2011
US scientists are hoping to uncover answers behind a mysterious disease that has emerged in Arctic seal populations, causing skin lesions, lethargy and death, officials said Friday. Since July there have been at least 107 recorded cases of stranded ringed seals on the north coast of Alaska, said researchers with the National Oceanic and Atmospheric Administration (NOAA) Fisheries and other i ... read more


ICE WORLD
Subtly Shaded Map of Moon Reveals Titanium Treasure Troves

NASA's Moon Twins Going Their Own Way

Titanium treasure found on Moon

NASA Invites Students to Name Moon-Bound Spacecraft

ICE WORLD
Mars Landing-Site Specialist

New Mystery on Mars's Forgotten Plains

Russian scientists want to join Europe's ExoMars mission

UK Space Agency announces seed funding for Mars exploration

ICE WORLD
Space tourism gaining momentum

NASA Veteran Alan Stern to Lead Florida Space Institute

Astrotech Subsidiary Awarded Task Order for NASA Mission

ASU in space: 7 current missions, more in the wings

ICE WORLD
China's first space lab module in good condition

Takeoff For Tiangong

Snafu as China space launch set to US patriotic song

Civilians given chance to reach for the stars

ICE WORLD
Ultrasound 2: Taking Space Imaging to the Next Level

CU-Boulder to play key role in global student space experiment competition

It's All in the Mix With Fluid Physics in Space

DLR ROKVISS robotic arm returns from space

ICE WORLD
Soyuz is put through its paces for Thursday's launch

Russia blames scientists for rocket crashes

Space Exploration Technologies Ready to Compete for Upcoming DoD Launches

Huge stakes riding on maiden Soyuz launch from Kourou

ICE WORLD
UChicago launches search for distant worlds

UChicago launches search for distant worlds

Astronomers Find Elusive Planets in Decade-Old Hubble Data

University of Texas-led Team Discovers Unusual Multi-Planet System with NASA's Kepler Spacecraft

ICE WORLD
Apple profit soars but misses high expectations

China rare earths giant halts output as prices fall

Camera lets people shoot first, focus later

German satellite to crash to Earth 'at the weekend'




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