Cluster scientific commissioning updates from ESOC
16 October 2000
The Cluster quartet, Salsa, Samba, Rumba and Tango, are now flying in their final orbit around the Earth in tetrahedral formation. Over the next few months all scientific instruments onboard the spacecraft will be gradually brought to life. The same instrument on each spacecraft will be switched on, one after another. Over a period of three months, starting on 23 August 2000, the instruments will undergo a series of health and calibration checks. By early December all 44 instruments on the four spacecraft will be operational and ready to start the scientific mission.16 October 2000
The commissioning is proceeding smoothly, with nearly half of the activities successfully completed. 11 instruments have been commissioned, 19 have started, and 14 have yet to be started.
The 8 wire booms on SC1 and SC2 have been completely deployed, with a total boom length of 88 m tip to tip. The first boom deployment on SC3 has also been successfully performed under ESOC control. Nine deployments have now been performed and 7 are still to be done (3 on SC3 and 4 on SC4). The wave instruments (DWP, EFW, STAFF,WBD, WHISPER) are almost finished with their commissioning on SC1 and SC2. Data are regularly obtained for WBD via the Deep Space Network (DSN).
FGM data acquisition is continuing. In addition, two hours of data are being acquired simultaneously on all four spacecraft every week to inter-calibrate the instruments.
ASPOC has finished its commissioning on SC2 and has commenced its operations on SC3.
The commissioning of the particle instruments (CIS, PEACE and RAPID) is completed on SC3 and on SC4 and will continue on 23rd October on SC1and SC2.
19 September 2000
Boom deployment is proceeding very well: on Monday night at 19:30 Z one pair of booms on spacecraft 2, Salsa, was extended from 35 metres to their full length of 41 meters. The other pair will remain at a length of 20 meters for an additional 11 days to allow further calibration measurements. The measurements made so far for calibration purposes have already allowed the scientists to make several interesting detections.
The next step will be the deployment of the two sets of booms on Rumba to 20 and 35 meters respectively, starting on Wednesday at 18:15 Z.
12 September 2000
Today saw further deployment of the experimental booms on Salsa. The two pairs of booms were extended from 15 meters to 20 and 35 meters respectively. As expected a spin rate of 12.3 rpm was maintained and no spin-up manoeuvre was necessary. On Monday the booms currently at 35 meters will be fully extended to their operational length of 43 meters. The spacecraft will then remain in this configuration for a couple of weeks to allow the team to perform instrument calibration at different boom lengths. Cluster Deputy Project Manager Alberto Gianolio expressed his delight at how smoothly the procedure went.
A similar procedure will be employed for Rumba in a few days. Samba and Tango will follow the same protracted sequence in early October. By the end of this painstaking procedure, each of the spacecraft will resemble rotating drums with four wire spokes, each 43 metres long, capped by a small sphere. The Cluster quartet will then be ready to receive the first real data from the five experiments that will use the antennae to study electromagnetic fields and waves in the Earth's magnetosphere.
7 September 2000
The Cluster mission will be booming over the next six weeks. During a carefully planned series of operations, 16 wire booms, each almost 50 metres in length, will gradually be released from the spinning satellites. Once they are fully deployed and begin to sweep out a giant circle around the spacecraft, these booms will provide a flood of data for the five wave experiments on each Cluster satellite.
More at: Boom time begins for Cluster
30 August 2000
Doom and gloom are currently affecting the Cluster project team, but there's no need for concern. It's just the start of the eclipse season for the four Cluster spacecraft. Over the next week, the quartet will periodically cease to be illuminated by the Sun as they sweep through the Earth's shadow.
More at: Cluster quartet go into eclipse
24 August 2000
Commissioning of the 44 instruments onboard the four Cluster spacecraft is now underway. ESA project scientist Dr. Philippe Escoubet, reported from ESOC that the Fluxgate Magnetometer (FGM) had been successfully commissioned onboard Rumba, Salsa and Samba. Commissioning of the FGM included a hardware check, mode changes and extended mode operations.
Located on a five metre long boom, the two magnetometers on each spacecraft will be used to measure the magnetic fields along the orbit. The FGM can take high-resolution measurements with up to 67 samples per second.
Professor Andri Balogh, the Principle Investigator (PI) for FGM, was reported to be very pleased with the results. Testing of the FGM instruments showed they were functioning well with very good preliminary offsets and better than expected alignment of the sensors on the five metre booms.
FGM commissioning for the fourth Cluster spacecraft, Tango, will be carried out today, along with the ion detector (CIS) on Samba and the electron gun (EDI) and wave instruments (WEC) on Salsa.
