1. SWWT Spacecraft, Aircrafts and Launchers Environments TWG
Federico Di Marco
VEGA Space
ESOC - European Space Operations Centre
ESWW8 01/12/2011 Namur, Belgium

2. Progresses in the field Spacecraft
ESWW8 01/12/2011 Namur, Belgium

3. Satellite Anomalies (1)
XMM - unexpected HLCL trip OFF on HLCL SEU – Accepted as is
XMM – unexpected LCL STA STRE2 tripped ON  SEU – Accepted as is
VEX - VIRTIS-H cooler anomaly not clearly identified the root cause
ESWW8 01/12/2011 Namur, Belgium

4. Satellite Anomalies (2)
Cluster - Latch-up of a memory module in Solid State Recorder (SSR) not clearly identified the root cause
Cluster - Unexpected Central Terminal Unit (CTU) switch-over not clearly identified the root cause
Cluster - Solid State Recorder overcurrent
not clearly identified the root cause
ESWW8 01/12/2011 Namur, Belgium

5. Satellite Anomalies (3)
Cluster - Unexpected switching ON of LCL RCS not clearly identified the root cause
MEX Safe Mode upon SSMM internal Invalid checksum event (3)not clearly identified the root cause
H-P both STRs reported ASIC RAM overflow not clearly identified the root cause (Radiation/bright object in FOV?)
ESWW8 01/12/2011 Namur, Belgium

6. Satellite Anomalies (4)
H-P Degradation of AADs/SASs
ESWW8 01/12/2011 Namur, Belgium

7. Satellite Anomalies (5)
1.Herschel satellite is operated in the positive range of SAA angels, due to a thermal problem
2. Planck SAS and AAD units are positioned at the back of the S/C. The X axis is continuously pointed at the sun
3. Herschel SAS and AAD units are positioned at the side of the S/C. This side is continuously pointed at the S/C, but that the SAA might vary during the orbit around L2.
4. The silicon chip orientation with respect to the sun is different between AAD and SAS. This will significantly impact on the effective thickness of the glass cover.
ESWW8 01/12/2011 Namur, Belgium

8. Satellite Anomalies (4)
SAS chip surface is always illuminated completely, while in the AAD only a small part of the surface is illuminated.
ESWW8 01/12/2011 Namur, Belgium

9. Satellite Anomalies (6)
Possible reasons for the degradation (especially for AAD) are:
degradation is due to the solar wind, highly directional and hitting the illuminated part of the chip more easily
Radiation dose calculations not adequate.
In the AAD the directional radiation of the solar wind will only see the cover glass of 300micron thick and will bypass the aluminium through the aperture No shielding of Aluminium is then present.
Radiation behaviour of the sun sensors has always been measured on 1 cm2 chips which are irradiated and illuminated in “flooded beams” (=entire active area involved).
Local / inter chip effects never been characterized.
These local effects might result in higher radiation degradation in the middle of the chip; this area is the operational region of the AAD.
degradation is not due to radiation but to pollution and UV carbonizing effects
For pollution events it is expected that due the initial out gassing period (couple of days) an initial sensor degradation will occur followed by a carbonizing period. An initial degradation period, with a strong degradation has not been observed.
ESWW8 01/12/2011 Namur, Belgium

10. Satellite Anomalies (7)
Preliminary conclusions
SAS degradation appears to be slowing down and is limited
Higher observed degradation especially related to the AAD
Difference in degradation between SAS and AAD is understood
Difference in degradation between Herschel AAD and Planck AAD likely related to the difference operational FOV usages.
Degradation of AAD is most likely related to radiation due to directional solar wind ?
ESWW8 01/12/2011 Namur, Belgium

11. Events 2011(1)
Largest solar energetic particle event of current solar cycle, 7-14 June
The peak counts for the >12 MeV proton channel were 20 /s and significant counts were measured in the higher energy protons channels. The total dose for this event was determined to be of the order of 10 Rad(Si) behind 4 mm Aluminium shielding.
Energetic Particle Telescope (EPT) on ESA Proba-V mission
Proba-V’s Energetic Particle Telescope (EPT) will record the charge, energy and angle of incoming charged particles along a wide range of energies across a 50° field-of-view.
The EPT flight model is due to be completed by the end of this year, with integration onto Proba-V in early The mission’s launch is scheduled for spring 2012.
Release of PROBA2 calibrated data both LYRA and SWAP (respectively the UV-EUV radiometer and the EUV imager on-board PROBA2)
ESWW8 01/12/2011 Namur, Belgium

12. Events 2011(2)
Call for interest on in-orbit validation of payloads hosted on-board Telecommunication satellites .
ESA is considering the possibility of further expanding its offer of in-orbit validation opportunities. Two opportunities have been identified:
1. The dedicated satellite (EDRS-C) in the EDRS programme planned to be launched by late 2014, allowing for the embarkation of up to 140 kg and 1.5 kW into geostationary orbit (GEO).
2. Up to 66 Hosted payloads of up to 50 kg and 50 W (200 W peak) each in the Iridium NEXT constellation in Low-Earth orbit (LEO). Launches start in 2015, with last launch in 2017
ESWW8 01/12/2011 Namur, Belgium

13. Services (1) SEDAT, for satellite design.
Programmable application and space environment database allowing expert user environment analysis
SPENVIS , for satellite design.
Web based access to space environment models and data
SEISOP for satellite operations/design.
Web based access to data from multiple ESA missions (MEX, VEX, ROS, INT, H-P, XMM) and external sources located worldwide. Access for external components, such as data mining and forecasting modules.
ESWW8 01/12/2011 Namur, Belgium

14. Services (2) EDID, for satellite design.
Resource for information on European impact detectors
ODI- Open Data Interface, for satellite design.
Database in MySQL common to SAAPS, SEDAT, and SPENVIS
IONMON , for ground system operations.
application producing TEC (Total Electron Content) maps in near real-time
ESWW8 01/12/2011 Namur, Belgium

15. Services (3) SWENET Portal , for data services.
Web based application including analysis tools, alerting functions and other services
SREM in-flight sensors and database , archive and latest data
Solar Dynamic Observatory (SDO) data available at the Royal Observatory of Belgium [ ].
Space Weather data services provided by PROBA2 [
ESWW8 01/12/2011 Namur, Belgium

16. Services (4) Space segment is vital for SW services:
Dedicated activity to address piggy-pack flight opportunities for next generation SWE instruments ongoing
=> over 20 European instruments representing all required instrument types considered
=> the short list for candidate host s/c includes about 25 missions planned for 2014 – 2020
ESWW8 01/12/2011 Namur, Belgium