1. The Solar-B Mission Len Culhane – EIS Principal Investigator
Louise Harra – UK EIS Project Scientist
Mullard Space Science Laboratory
University College London

2. SUMMARY
The Solar-B mission is outlined and the instruments described – EUV Imaging Spectrometer (EIS) in more detail
Solar-B mission operations are described
proposal submission is discussed
EIS planning software is summarized
possible joint observations with other missions suggested
The Solar-B priority science plan for the first 90 days after commissioning is reviewed
ISSI – Proba Team, 21st June, 2006

3. Solar-B Spacecraft EIS - MSSL/NRL/BIRM/RAL → EUV Imaging Spectrometer
SOT - ISAS/NAOJ → Solar Optical Telescope
XRT - SAO/ISAS → X-ray Telescope
FPP - Lockheed/NAOJ → Focal Plane Package
EIS
SOT
FPP
XRT
EIS – UiO → QL Software
ESA/NORWAY → Svalbard Ground
Station
ISSI – Proba Team, 21st June, 2006

4. Mission Characteristics
Launch date: 23rd September, 2006
Launch vehicle: ISAS MV
Mission lifetime: 3 years
Orbit: Polar, Sun Synchronous
Inclination: 97.9o
Altitude: 610 km.
Mass: 900 kg
Mission control: ISAS/Uchinoua
Data downlink:
Uchinoura → 4 orbits/day
Svalbard → 15 orbits/day
ISSI – Proba Team, 21st June, 2006

5. Solar-B Science Summary
Establish the mechanisms responsible for heating the corona in active regions and the quiet Sun
Active region evolution
Nature of sub-photospheric magnetic flux tubes
Upper atmosphere heating and wave energy
Determine the mechanisms responsible for transient phenomena, such as flares and coronal mass ejections
Flares and the role of magnetic reconnection
Photospheric magnetic field helicity and CMEs
Investigate the processes responsible for energy transfer in the quiet Sun
Origin and nature of quiet Sun magnetic fields
Flux cancellation and ephemeral regions
Network and weak internetwork magnetic fields
ISSI – Proba Team, 21st June, 2006

6. Solar-B Mission Instruments
Solar Optical Telescope (SOT)
Largest optical telescope (d = 0.5m) to observe Sun from space
Diffraction-limited (0.2 – 0.3 arc sec) imaging in range 3880 – 6680 Å
Vector magnetic field and velocity measurement at the photosphere
X-Ray Telescope (XRT)
High angular resolution ( < 2 arc sec) coronal imaging
Wide temperature coverage: 1 MK < Te < 30 MK
EUV Imaging Spectrometer (EIS)
Coronal raster imaging at 2 arc sec
Plasma diagnostics (Te, ne, v) in 170 – 210Å and 250 – 290Å ranges
ISSI – Proba Team, 21st June, 2006

7. FPP Optical Component Layout
Littrow Mirror
Folding Mirror
448 x 1024 CCD
Scanning Mirror
Polarizing BS
X3 Mag lens
Folding Mirror
Shutter
Slit
Field lens
Grating
Field lens
Preslit
X2 Mag lens
Shutter
2048 x 4096 CCD
Filterwheel
Birefringent Filter
Telecentric
lenses
Field Mask
Beam Distributor
Secondary
Primary
CLU
Tip Tilt Mirror
Filterwheel
50 x 50 CCD
Reimaging Lens
Folding Mirror
OTA
Common Optics CT
NFI
BFI SP
Demag lens
Image Offset Prisms
Folding Mirror
Polarization Modulator
ISSI – Proba Team, 21st June, 2006

8. Filtergraph Fields of View
Rectangle shows the Narrowband Filter FOV, 320 x 160 arc
sec with 0.08 arc sec pixels (4096 x 2048)
- inner square is 160 x 160 arc sec
Broadband Filter system
has higher magnification
(0.053 arc sec pixels) to
preserve SOT diffraction-
limited resolution
Broadband Filter FOV is
216 x 108 arc sec
Both filter systems share
a single CCD.
ISSI – Proba Team, 21st June, 2006

9. Filtergraph Observables
Filtergrams
Broad-band Filter Imager: all 6 bands - only observable made by BFI
Narrow-band Filter Imager: all 9 lines and nearby continuum
Dopplergrams
Images Doppler shift of a spectral line - line of sight velocity
Longitudinal Magnetograms
Location, polarity and estimate of flux of magnetic field components along the line-of-sight
Stokes Parameters I, Q, U, V
Analysis of I, Q, U, V at multiple wavelengths in a spectral line yields vector magnetic field measurements → vector magnetograms, also from spectropolarimeter
ISSI – Proba Team, 21st June, 2006

10. Solar-B X-ray Telescope (XRT) Schematic
Grazing incidence telescope; average glancing angle 0.9o
PSF and detector pixel sizes are ~ 1 arc sec
– resolution ~ x 2.5
better than Yohkoh
SXT
Ageom is 3.3 cm2
Focal length is 2.7m
Inner diameter is 35cm
CCD (2k x 2k) gives
full-sun (33”) images
Focus adjustment for
optimum on-axis or
wide field resolution
ISSI – Proba Team, 21st June, 2006

11. X-ray Telescope Response
Telescope has ~ three times greater effective area than Yohkoh SXT
Nine filters cover 1 MK < Te < 30 MK with Te resolution D (log Te) = 0.2
White light (G-band) solar images can be registered on the CCD at one filter
wheel position; allows X-ray and EIS to visible image alignment
XRT full-Sun observables:
→ 33 arc sec X-ray & white light images
ISSI – Proba Team, 21st June, 2006

12. EIT and TRACE - EUV Coronal Images
Impact of better XRT resolution is
shown in a comparison of SOHO EIT
and TRACE EUV images
Resolution of XRT betters that of the
Yohkoh SXT by the same margin (x 2.5)
as a) TRACE images better b) EIT images
The SXT and TRACE images shown are
on the same scale and are of the same
coronal structures
In full-disk mode, the effective resolution
improvement over Yohkoh SXT is ~ x 5 b a
ISSI – Proba Team, 21st June, 2006

13. EIS - Instrument Features
Large Effective Area in two EUV bands: Å and Å
Multi-layer Mirror (15 cm dia ) and Grating; both with matching optimized
Mo/Si Coatings
CCD camera; Two 2048 (l) x 1024 high QE back illuminated CCDs
Spatial resolution: 1 arc sec pixels/2 arc sec resolution
Line spectroscopy with ~ 25 km/s pixel sampling
Field of View：
Raster: 6 arc min × 8.5 arc min;
FOV centre moveable E – W by ± 15 arc min
Wide temperature coverage: log T = 4.7, 5.4, K
Simultaneous observation of up to 25 lines
ISSI – Proba Team, 21st June, 2006

14. EIS Optical Diagram Primary Mirror Entrance Filter CCD Camera
Grating
Front Baffle
Entrance Filter
Primary Mirror
CCD Camera
ISSI – Proba Team, 21st June, 2006

15. Slit and Slot Interchange
Four slit/slot selections available
EUV line spectroscopy - Slits
- 1 arc sec  512 arc sec slit - best spectral resolution
- 2 arc sec  512 arc sec slit - higher throughput
EUV Imaging – Slots
- Velocity information overlapped
- 40 arc sec  512 arc sec slot - imaging with little overlap
- 250 arc sec  512 arc sec slot - detecting transient events
ISSI – Proba Team, 21st June, 2006

16. for 40 arc sec Slot Imaging
Strong Isolated Lines
for 40 arc sec Slot Imaging
Short Wavelength Band
Ion l (Å)
Fe XI
Fe XXIV
Ca XVII
Fe XII
Fe XIII
Fe XIII
Long Wavelength Band
Ion l (Å)
Fe XXIV
He II
Fe XVI
Fe XIV
Fe XIV
Fe XV
ISSI – Proba Team, 21st June, 2006

17. EIS Field-of-View
512 
900 
Raster-scan range
Shift of FOV center with coarse-mirror motion
250 
slot
40 
360 
512 
EIS Slit
Maximum FOV for raster observation
ISSI – Proba Team, 21st June, 2006

18. EIS Effective Area
Primary and Grating: Measured - flight model data used
Filters: Measured - flight entrance and rear filters
CCD QE: Measured - engineering model data used
Following the instrument end-to-end calibration to ± 25%, analysis suggests
that above data are representative of the flight instrument
ISSI – Proba Team, 21st June, 2006

19. Science Observables Observation of single lines w
Observation of single lines
Line intensity and profile
Line shift () → Doppler motion
Line width (w) and temperature → Nonthermal motion
Observation of line pair ratios
Temperature
Density
Observation of multiple lines
Differential emission measure
ISSI – Proba Team, 21st June, 2006

20. EIS Sensitivity Detected photons per 11 per 1 sec exposure Ion
Wavelength
(A)
logT
Nphotons AR
M2-Flare
Fe XVI
251.07
6.40 -
108
Fe XXII
253.16
7.11 71
Fe XVII
254.87
6.60
109
Fe XXVI
255.10
7.30
3.3103
He II
256.32
4.70 16
3.6103
Si X
258.37
6.11 14 62
262.98 15
437
Fe XXIII
263.76
7.20
1.2103
Fe XIV
264.78
6.30 20
217
270.51 17
104
274.20 76
Fe XV
284.16
6.35
111
1.5103
Ion
Wavelength
(A)
logT
Nphotons AR
M2-Flare
Fe X
184.54
6.00 15 36
Fe XII /
6.11
13/21
105/130
Fe XXI
187.89
7.00 -
346
Fe XI /
41 / 15
110/47
Fe XXIV
192.04
7.30
4.0104
192.39 46
120
Ca XVII
192.82
6.70 31
1.8103
193.52
135
305 /
241/16
538/133
Fe XIII
200.02
6.20 20
113
202.04 35 82 /
7/20
38/114
ISSI – Proba Team, 21st June, 2006

21. Solar-B Mission Operations

22. Solar-B Mission Data Acquisition
SOT/FPP Data a) b) c)
Data are stored on-board in 8 Gbit memory
Instrument memory allocations are:
- SOT/FPP → 70%
- EIS/XRT → 15% each
Data downlinked to Svalbard ground
station (ESA/Norway) on 15 orbits/day
- memory dumped once per orbit
EIS average data rate → 45 kbps
Command uplinks only from Uchinoura
- four memory dumps per day
Quick-look assessed at ISAS and Uchinoura
ISSI – Proba Team, 21st June, 2006

23. Solar-B Mission Data Distribution
Level-0 and Cal Data
Level-2 Data (FPP)
Level -
Reformat
Solar
B Database
in Japan
in US
in UK
FPP Level 1
and -2
Reformat at Lockheed
Data distributed to UK, US and
Norway in compressed level – 0
form
Because of complexity, FPP
data are transmitted in level – 0
form to Lockheed Palo Alto
They are processed to level – 2
to produce vector and scalar
magnetograms
These products are then sent
to Japan and onward to UK
and Norway
ISSI – Proba Team, 21st June, 2006

24. Solar-B Mission Operations Mission operations will be conducted
from the ISAS Spacecraft Operations
Centre in Fuchinobe, Japan
Solar-B team observing plans and
community proposals will be discussed
at monthly meetings
Each instrument team will have a
Scientific Schedule Coordinator who will
organize the preparation of instrument
proposals and their integration in the
overall mission observing plan
Weekly and daily planning meetings
allow flexibility to respond to changing
solar conditions
ISSI – Proba Team, 21st June, 2006

25. Operations Roles A) Solar-B Mission
Solar-B Chief Planner (CP)
Provided by the instrument teams in rotation, one week shifts
Chief Planner Assistant (CPA)
Scientific Schedule Coordinators (SSC)
One for each instrument
Assistance from other participating countries
EIS SSC based in MSSL with visits to Japan
B) Individual Instruments (EIS-specific Roles)
Chief Observers (CO) (SOT, XRT, EIS):
One person for each instrument, one week shifts
Instrument Software Coordinators (ISCO):
EIS person initially at ISAS, then at MSSL; planning software from RAL
Instrument System Engineers (ISE):
EIS person at ISAS for commissioning, then at MSSL
ISSI – Proba Team, 21st June, 2006

26. EIS Operations Staffing
NRL
UK/Norway/Japan
Bradley
Sun
Culhane
Harra, Other UK
Mariska
MSSL
(x5)
Doschek
RAL
(x2)
Rainnie
Young
EIS Planner 3
weeks each)
Landi/Warren
Norway
(x2)
GSFC/Davila
Hansteen
Wikstol
NAOJ
(x2)
ISAS
GMU/Dere
Hara
Watanabe
Discussion points for this slide:
To point out the extent of the NRL activities, including the work done in the UK;
I will ask Clarence to summarize the UK activities and to emphasis the complexity of the NRL delivered components
Post Doc/
Brooks
ISAS On-Site
(1 year)
Post Doc/
MSSL
ISAS On-Site
(1 year)
Williams
First year of operation (Minimum)

27. EIS Planning Tool Software
Planning tool software is in SSW
Users will need to install the EIS SolarSoft tree
Study Definition
Line Lists
Raster Definition
Planners then export studies to ASCII format
a formatted file and a science case to a dedicated account at MSSL
ISSI – Proba Team, 21st June, 2006

28. EIS Planning Tool - line list interface
ISSI – Proba Team, 21st June, 2006

29. Planning Tool – make/edit raster
ISSI – Proba Team, 21st June, 2006

30. 5. Planning Tool – make/edit study
ISSI – Proba Team, 21st June, 2006

31. Solar-B Mission Science for the First 90 Days

32. SOT Initial Science Plan
Active region tracking:
- Emerging AR
- Mature/decaying AR
- Flaring AR
- Subsurface flows
- MHD waves
Quiet Sun:
- Network flux dynamics
- Internetwork flux
- Convective flow structure
Irradiance:
- Activity belt
- Polar regions
Prominences/Filaments
- Prominence at limb/Filaments on disc
- Track boundary evolution
ISSI – Proba Team, 21st June, 2006

33. XRT Initial Science Plan
Flares from dynamic AR on disk:
 Follow AR across disk, flare program loaded
- Deploy range of filters and FoV sizes
- Flare topology and energetics
Track modest (emerging or decaying) active region on disc:
 Image with large, medium and small FoVs
- Structure, energetics and dynamic behaviour
- AR evolution; track centre to limb?
Quiet Sun/X-ray Bright Points:
 Multi-filter study of bright points
- Thermal structure and dynamics
- Life-cycle statistics
Quiet Sun/coronal holes
 Single filter for boundary imaging
- Track boundary evolution
Quiet Sun/filament
 Magnetic structure around filament
- Track filament for 1-2 days
ISSI – Proba Team, 21st June, 2006

34. EIS Initial Science Plan
Flare trigger and dynamics:
 Spatial determination of evaporation and turbulence in a flare
- Characterize AR topology
- Measure key structures in detail
- Flare trigger response for early velocity measurement
Active region heating:
 Spatial determination of v, Te and ne in active region structures
- High time cadence sit and stare observations; dynamics
- Observe AR global changes
- Velocity measurements (± 3 km/s)
Quiet Sun and coronal hole boundary:
 Correlate coronal Te, ne and v with magnetic topology
- Study corona above two supergranule cells
- Study corona above bright point or explosive event
- Observe above a coronal hole boundary
Quiet Sun and Prominences (assume no available AR)
 Spatial determination of v, Te and ne in surrounding regions
-Register and follow eruption
ISSI – Proba Team, 21st June, 2006

35. 90 Day Observing Programme Summary
Topic
SOT
XRT
EIS
AR Tracking
a) Emerging AR √
b) Complex AR/Flares
c) Decaying AR
Quiet Sun a) Network
Small events/
Bright Points
Quiet Sun b) Intra-network
Small events/ Bright Points
Spicules
Magnetic connections
Prominences/Filaments
ISSI – Proba Team, 21st June, 2006

36. 90 Day Observing Programme Summary
Topic
SOT
XRT
EIS
Helioseismology/AR Tracking √
Helioseismology/QS/
Disc centre
Helioseismology/
Polar regions
Coronal Holes
Coronal Holes/
Polar Plumes
Irradiance/
a) AR Tracking
√/irradiance?
b) Activity belt repointings
Small events
Coronal Hole Boundaries
ISSI – Proba Team, 21st June, 2006

37. EIS Core Science Programme
AR Heating → dynamic phenomena in loops
Coronal/Photospheric velocity field comparison in AR
Coronal Seismology → waves in AR structures
AR Helicity content → CMEs, magnetic clouds
Evolution of trans-equatorial Loops
Flare produced plasma → source, location and triggering
Flare reconnection → inflow and outflow
Quiet Sun transient events → network, network boundaries, CH boundaries, size scales
CME Onsets → dimming, filaments, flux-ropes, flaring AR, trans-equatorial Loops
Evolution of large coronal structures → streamers, large-scale reconnection, slow Solar Wind
ISSI – Proba Team, 21st June, 2006

38. Some Possible Joint Observations
Solar-B Instruments:
Active Region study campaign (SOT/EIS/XRT)
Emission measure distributions in AR structures (EIS/XRT)
AR helicity content and CME launches (SOT/EIS/XRT)
Magnetic topologies in small events (SOT/EIS/XRT)
Network and intra-network small event energies and velocities (EIS/SOT)
Plasma and magnetic structures above Coronal Hole boundaries (EIS/SOT)
Reconnection flows in flares (EIS/XRT)
Other Missions:
CME launching, topology and magnetic clouds (Solar-B, STEREO, ACE)
CME dimming outflow velocities; their relation to CMEs (Solar-B/EIS, STEREO)
Trans-equatorial loop and filament eruptions (Solar-B/EIS, XRT, STEREO)
Coronal (EIT) waves and their relation to CMEs (Solar-B/EIS, XRT, STEREO)
Intensity and velocity studies of waves in AR structures (Solar-B, TRACE, SDO)
Impulsive flares and sub-surface wave propagation (Solar-B, TRACE, SDO)
ISSI – Proba Team, 21st June, 2006

39. END OF TALK
ISSI – Proba Team, 21st June, 2006

40. Processed Science Data Products
Intensity Maps (Te, ne):
– images of region being rastered from the zeroth moments of
strongest spectral lines
Doppler Shift Maps (Bulk Velocity):
– images of region being rastered from first moments of the
Line Width Maps (Non-thermal Velocity):
– images of region being rastered from second moments of
the strongest spectral lines
ISSI – Proba Team, 21st June, 2006

41. EIS Data Flow CCD Readout Electronics EIS ICU S/C MDP
Data compression
DPCM(loss less) or 12bit-JPEG
Small spectral
window (25 max)
CCD Readout
Electronics
2Mbps max
1.3 Mbps
EIS ICU
S/C MDP
control
Large hardware
CCD window
Observation table
 250 kbps max
for short duration,
 45 kbps average
1 slit obs. 40 slot obs  slot obs.
Spec.width
Spatial width " " "
No. of lines
Compression 20% % %
Cadence sec sec sec
Rate kbps kbps kbps
Average rate depends
on number of downlink
station.
Telemetry
data format
10 min cadence for 44 rastering
ISSI – Proba Team, 21st June, 2006

42. Installation of Key Subsystems in Structure
Primary Mirror
Grating
Dual CCD Camera
Filter Holder Installed
EIS Instrument Completed
Entrance Filter Holder
ISSI – Proba Team, 21st June, 2006

43. Vector Magnetograms
Spectra of two Fe lines at Å and Å and nearby continuum are
exposed with a 0.16 x 164 arcsecond slit
The Spectro-polarimeter (SP) can scan across a 160 x 320 arc sec FOV while
the CT and Filter FOVs are fixed
In normal mode, the SP scans
160 arc sec in 83 min
Fast maps are 2.8 times quicker
hence 160 arc sec in 30 min
Magnetic field measurement:
- B (longitudinal) to ± 3 G
- B (transverse) to ± 30 G
- Field direction to ± 1o
ISSI – Proba Team, 21st June, 2006

44. Velocity Measurement Accuracy
Bright AR line
Flare line
Photons (11 area)-1 sec-1
Photons (11 area)-1 (10sec)-1
Doppler velocity
Line width
Number of detected photons
ISSI – Proba Team, 21st June, 2006

45. EIS and XRT Science Coronal heating mechanisms
- Multi-filter XRT and multi-line EIS slot images study thermodynamic properties of coronal structures
EIS and XRT can show the AR coronal structures that have significant large scale flows
Rapid intensity fluctuations observed by XRT combined with velocity maps from EIS and SOT Dopplergrams will
establish role of waves and flows in different parts of an AR
Magnetic reconnection and coronal dynamics
XRT will observe statistically significant numbers of small reconnection events
Comparing location, energetics, and duration of these events (XRT, EIS, and SOT filtergrams) with evolving
photospheric magnetic field will allow first quantitative study of
- conditions necessary for reconnection
- efficiency of the reconnection
- coronal impact of the reconnection
Photospheric-coronal coupling
For ARs, need to trace magnetic connectivity → photosphere – chromosphere -corona
Spectral imaging with EIS and SOT
- allows identification of loop footpoints
- associates footpoints with photospheric magnetic features
Flare events and coronal mass ejections.
Topological properties of flares and CMEs studied using non-linear force-free field models from SOT vector data
- Follow AR evolution and identify the coronal sites of flare or CME initiation
- Discover magnetic null points above flaring active regions and track AR magnetic helicity changes
ISSI – Proba Team, 21st June, 2006

46. EIS Instrument Calibration
If fl in photons cm-2 s-1 sr-1 is the intensity of the solar radiation at wavelength
l, the number of photons registered in each detector pixel per second is:
Nl = fl A wd Tffa(l) Tspider Rm(l) Tsef(l) Eg(l) Ed(l) where
A is the mirror geometric area and wd is the solid angle per detector pixel
Tspider is the transmission of the entrance filter spider support structure
Tffa(l), Tsef(l) are the transmissions of the Al entrance and spectrometer filters
- filters on an 85% transmission support mesh which is included in T values
Rm(l), Eg(l) are the coated mirror and grating efficiencies
Ed(l) is the CCD detector quantum efficiency
ISSI – Proba Team, 21st June, 2006

47. EIS Calibration Spectra – 250" Slit
Calibration has been carried out with the source
used for SOHO CDS calibration
(Hollandt et al., 2002, Lang et al., 2000)
Source is radiometrically calibrated by PTB, Berlin
at the BESSY I electron storage ring
Stable high-current hollow-cathode discharge lamp
provides appropriate EUV emission lines
Following EIS calibration, the source will be re-
calibrated at BESSY II
NRL Penning source also used for alignment and full
aperture illumination
ISSI – Proba Team, 21st June, 2006

48. EIS Calibration Spectrum – 2" Slit
Al III, Al IV and Ne IV lines
ISSI – Proba Team, 21st June, 2006

49. Nonthermal Velocity in FlaresTe
Gradual increase of vnt at the precursor phase of a flare is reported by Harra, Matthews, & Culhane (2001).
Detecting of flares in a slit scanning observation is the only way to identify this precursor.
Identification of site of large non-thermal velocity in imaging spectroscopy will be very important in understanding the physics of precursor phase.
vnt
vnt
I (S XV)
vnt
BATSE Ch 1
Harra, Mattews, & Culhane 2001, Ap.J, 549, L
ISSI – Proba Team, 21st June, 2006

50. Reconnection Inflow
Evidence of 2D-reconnection inflow for a long-duration event is reported by Yokoyama et al. (2001) from an EUV imaging observation
EIS will detect the reconnection inflow as a Doppler shift in emission line spectra
Observation near the limb will be important to detect reconnection inflow
Hot reconnection outflow may be detected in Fe XXIV slot observations
Movie sequence
From Yokoyama et al. 2001, ApJ, 546, L69-72
ISSI – Proba Team, 21st June, 2006

51. Coronal Mass Ejection Onset
Coronal dimming directly associated
with outflow (Harra & Sterling, 2001)
Bottom panel shows a CDS O V
velocity map for a disc event where
~ 80 km/s outflow is seen from the
edge of the dimming region
CDS limb event observations show
intensity reduction and outflow
velocities in He I, O V, Mg IX and
Fe XVI
Using EIS:
- select HeII, SiVII, Fe X, Fe XIII, Si
X, Fe XIV, Fe XV, Ca XVII lines
- raster slit over 6’ x 8’ in 30 min.
- raster 40” slot over 6’ x 8’ in 1 min.
Respond more quickly to dimming
onsets
ISSI – Proba Team, 21st June, 2006

52. Coronal Hole Boundaries
CH boundaries are not
well understood
- EIS will determine the
velocity field in this
important region.
Using EIS:
- Select HeII, SiVII, Si X,
Fe XII, Fe XI, Fe X lines
- Sit and stare studies with
the 1" slit alternated with
300" x 300" rasters
Movie sequence
ISSI – Proba Team, 21st June, 2006

53. Instruments and Spacecraft Bus
Following completion of final
thermal vacuum test
(20th March to 4th April, 2006):
 Instruments separated
 Work in progress on
ACS system in bus
module
EIS flight filters were installed
on Monday, 19th June
Spacecraft arrives at the
Uchinoura launch site on
1st August
Bus
Module
Instruments
ISSI – Proba Team, 21st June, 2006