1. Ben Gurion University Mission scientists (PI's) : Gérard Dedieu & Arnon Kanieli G. Dedieu 1, O. Hagolle 2, A. Karnieli 3, S. Cherchali 2 P. Ferrier 2 and Y. Yaniv 4 The VENμS mission: Earth Observation with High Spatial and Temporal Resolution Capabilities 1 CESBIO, Toulouse Cedex 9, France 2 CNES Toulouse France 3 The Remote Sensing Laboratory, Ben Gurion Univ. of the Negev, Israel 4 MBT Space Division, Israel Aircraft Industries ISRAEL

2. VEN  S  VEN  S is an Earth observation scientific mission jointly developed by CNES, the French space agency, and ISA, the Israeli Space Agency  Objectives :  To provide data for research on land surface functioning : land cover & land use, water and carbon exchanges, snow Data assimilation Automatic land cover mapping Validation of medium resolution satellite products Demonstration of the use of RS data for the implementation of Environmental regulations (e.g. Grenelle laws in France)  To investigate and demonstrate the benefit for Earth sciences and applications of high repetitivity, high resolution remotely sensed measurements acquired by a super spectral imaging radiometer  To develop and experiment a dedicated ground segment able to deliver state of the art quality products

3. Why high temporal repetitivity ? June 5 th 2006June 14 th 2006June 23 th 2006June 29 th 2006 (rapeseed harvest, sunflower growth) Formosat-2 images

4. Indice foliaire 2006

5. VEN  S Uniqueness - Summary  Temporal resolution 2 days revisit time for monitoring rapid changes : objective of a cloud free (composite) image every 7 or 10 days  Spectral resolution Super spectral sensor – 12 spectral bands VIS-NIR for land applications  Spatial resolution Pixel size of 5.3 m for Level 1, 10m for level 2 and 3. Registration requirement: 3 m rmse  Tilting capability 30 deg across and along track  View angle Constant view angle can be achieved every 2 days, at constant local solar time  Stereo pairs with a small angle difference at 620nm Cloud screening based on altitude, DEM generation

6. Ven  s Orbits Altitude: 720 km Inclination: 98.27° Sun-synchronic LST : 10h30 DAY 1, 3, 5, 7 …

7. Ven  s Orbits Altitude: 720 km Inclination: 98.27° Sun-synchronic LST : 10h30 DAY 2, 4, 6, 8 …

8. Ven  s Orbits Altitude: 720 km Inclination: 98.27° Sun-synchronic LST : 10h30 2 days cycle: day 1 & day 2 orbits

9. Ven  s Acquisitions: tilting capability ± 30° along/across track

10. Ven  s Orbits and observing capabilities DAY 1 DAY 2 ± 30° Tilt

11. DAY 1 DAY 2 ± 30° Tilt Ven  s Orbits and observing capabilities

12. Altitude: 720 km Inclination: 98.27° Sun-synchronic LST : 10h30

13. VEN  S Imaging capabilities  Swath: 27.56 km  Nominal requirements  50 sites of 27x 54 km + calibration and image quality sites  140 images of 27x27 km within 2 days (>20000/year)  30 images on the most demanding orbit  Data strips longer than 54 km are feasible  Angular sampling could be achieved for a few sites (± 30° roll and pitch)  Moon viewing for calibration

14. Camera : Band Setting Simulated vegetation reflectances for 3 different Chlorophyl content

15. Band Setting (Requirements) Bands 0 (μm) Δ (nm) SNR for Lmin at 5.3GSD Required Resolution (meters) SNR for Lmin at resolution Main Driver B10.420402521.2100 Aerosols B20.443402521.2100 Aerosols, clouds B30.490402521.2100 Aerosols B40.555405010.6100 Land B50.620405010.6100 Land B60.620405010.6100 DEM, image quality B70.667304510.690 Land B80.702245510.6110 Land B90.742165510.6110 Land B100.782165510.6110 Land B110.865405010.6100 Land B120.910202521.2100 Water vapor

16. Image quality  Needs  Spatial and temporal image composites that can be used over a whole area to monitor seasonal and interannual evolutions  Need to provide consistent and homogeneous measurements through time and space, with physical meaning (reflectances)  Requirements  Geometrical registration (within bands  0.25 pix, multitemporal 3m)  Radiometric calibration (3-5%), knowledge of the spectral responses, and spectral stability  Minimisation of perturbing effects : directional and atmospheric. Maximum shift of the time of overpass throughout the mission duration: lower than ± 5 minutes – Constant view zenith angle ± 2 degrees

17. Ground segment : Products Level 1: single acquisition Geometrically corrected (maps) of top of the atmosphere reflectances. One map projection per site. Level 2: single acquisition, geophysical variables Surface reflectances, atmospheric water vapor content and aerosol optical depth Level 3 : time composite, geophysical variables Surface reflectances, atmospheric water vapor content and aerosol optical depth All the acquired images will be freely available by ftp less than 1 month after acquisitions

18. Sites’ selection  Deadline for outline proposals of Ven  s sites and data use was 28th june 2006  Proposals for additional sites are still considered, as second priority, if they are located in regions with little demands  Simulation of sites acquisitions is being carried out : technical feasibility, trade-off scenarios  Selection of the sites is still pending on technical issues  The plan is to acquire images over the selected sites during the whole 2.5 years of the mission

19. Objective of the workshop  Present the current status of the mission  Present levels 2 and 3 algorithms and existing/forthcoming data-sets  Illustrate the benefit of the mission by some examples  Answer your questions  Networking of scientists interested by the Venµs mission and more generally by high resolution/high repetitivity data  Listen to your needs and requests  Discussion on possible additional products or innovative uses  Coordination of efforts in the frame of calls for proposals (Tosca, PNTS, Interreg, FP7, …) and Sentinel-2 preparation