. 24/7 Space News .
Double Star Instrument Commissioning Started

Double Star and Cluster complementary orbits. The four Cluster spacecraft are in the solar wind and Double Star is crossing the bow shock at the same time. Larger image
Paris - Jan 27, 2004
The first Double Star spacecraft was successfully launched from Xichang, Southern China, on 29 December 2003 at 19:06 UT. The final operational orbit is 570 by 78 970 km, with an inclination of 28.5 degrees. Due to an over-performance of the upper stage the apogee is about 12 000 km more than expected.

This should not affect the scientific objectives. Furthermore, the spacecraft will now observe the Earth bow shock, which was not in the original scientific objectives. A preliminary estimate reveals that that the number of conjunctions with Cluster has decreased slightly, but this is compensated by the longer time interval for each individual conjunction.

Spacecraft Status: One solid boom, carrying the fluxgate magnetometers (FGM), has been deployed successfully. The other one, carrying the search coil (STAFF/DWP), is still un-deployed after an initial attempt to deploy it. Chinese spacecraft engineers are investigating the source of the problem and will make another attempt in the next few weeks. This, however, does not affect the stability of the spacecraft and the spin axis is as expected close to the North ecliptic pole.

Instrument Commissioning started in early January:
FGM
Commissioning Status: Tests started on 8 January and after 4 days the instrument electronics were checked-out successfully.
Current Operations: Data acquisition is now taking place to calibrate the instrument.

STAFF/DWP
Commissioning Status: Has finished its initial commissioning
Current Status: Instrument is functioning nominally.

Both instruments have detected an electromagnetic noise, which is likely related to the boom asymmetry causing solar array shadowing; an investigation is on going to identify the source and try to eliminate it.

PEACE (electron detector)
Commissioning Status: Started first electronic tests on 20 January and is working nominally. Some software tuning is still on going to optimize the on-board compression algorithm. Current operations: An increase in solar activity (M6.1 flare) started on 21 January and an interplanetary shock arrived at the Earth on 22 January around 01:35 UT. The effect on the magnetosphere was a big compression, due to the increased pressure of the solar wind by about 5 times more than usual, and the Earth bow shock was pushed toward Earth and passed the Double Star located at 12.6 Earth radii, as indicated by preliminary PEACE data. The Cluster spacecraft were also in the solar wind and observed the interplanetary shock and this conjunction should allow a very detailed study of the event.

ASPOC (ion emitter)
Commissiong Status: Covers were opened successfully on 5 January and instrument commissioning will began on 24 January
Current operations: Three ion emitters were successfully ignited and are working nominally. The fourth, and final emitter, will be ignited during the next communications visibility slot on 28 January.

HIA (ion detector)
Commissiong Status: Commissioning will begin in first half of February

In other news ESA can report that all three European experiments are being delivered to Beijing for the second Double Star spacecraft, which will start its integration early February for a launch in July 2004.

Related Links
Double Star
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express
 Joint Chinese/European Mission Ready For Launch
Paris (ESA) Dec 23, 2003
On 27 December, the Chinese National Space Agency (CNSA) will launch the first of two scientific satellites known as Double Star. ESA is contributing to this Double Star mission by providing eight on-board scientific instruments.



Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only














The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - 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.