PICASSO PICo-satellite for Atmospheric and Space Science Observations

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2 PICASSO PICo-satellite for Atmospheric and Space Science Observations A scientific CubeSat mission Fussen D., Anciaux M., Bonnewijn S., Cardoen P., Dekemper E., De Keyser J., Demoulin Ph.,, Pieroux D., Ranvier S., Vanhellemont F. contact: Didier.Fussen@oma.be

3 ALTIUS: still in phase B1 (after 10 years!) PICASSO, the future of remote sensing? Affordable, fast development, evolutive and slightly risky!!! - 3 -

4 Strategic objectives At BISA, we believe that pico- and nano-satellites could very well play an important role in the Earth observation in a near future: They are cheap and thus can be deployed as a fleet and be spread all around the Earth, improving the spatio-temporal coverage of the measurements Due to the fleet innate redundancy, individual failures are not catastrophic They can be used to test new instrument concepts at a much cheaper cost They are accessible to small countries, and even to institutions So, why not to demonstrate their potential through a genuine scientific mission? Objective: to demonstrate Science in a CubeSat mission VISION, a visible and near-infrared hyper-spectral imager: vertical profiles retrieval of the ozone density and of the T via Sun occultations SLP, a Sweeping multi-needle Langmuir Probe: electronic density and T of the plasma - 4 -

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6 PICASSO, the project CubeSat mission, embarking 2 scientific experiments for Earth observation: VISION, to retrieve vertical profiles of ozone and t, via Sun occultation SLP, to study the ionosphere (e -, ions and t ) - 6 -

7 The project set-up 2009: initiated by the Belgian Institute for Space Aeronomy accepted as ESA In-Orbit Demonstrator kick-off on 21 October 2014 Belgian Institute for Space Aeronomy (BEL), prime: management mission definition & scientific aspects (incl. data analysis) whole development of SLP & software of VISION VTT (FIN): manufacturing of the VISION hardware Clyde-Space (UK): platform development & payload items integration tests, ground-station & operations Centre Spatial de Liège (BEL): system engineering and PA/QA Launch: mid-2016? Mission duration: min. 2 years Status : PDR successfully completed on 10 July

8 The platform: Clyde-Space Ltd, UK Triple unit CubeSat (one unit left for the payload) o rigid structure, specifically designed for PICASSO o very light: 332 g Four deployable 2-unit long solar panels - 8 -

9 The platform: Clyde-Space Ltd, UK Attitude control: o inertial flight, one face towards the Sun o pointing accuracy: ~1 (knowledge: 0.2 ) o 3 reaction wheels + magneto-torquers o star tracker o fine Sun sensor o GPS Total mass estimated at 3.7 kg Power budget: 10 W generated, 7.5 W needed Telecom: o uplink: VHF; downlink: UHF + S-Band o data volume estimated at 52 MB/day - 9 -

10 Solar occultation Observation of sunsets and sunrises through the Earth s atmosphere Occultation technique is self-calibrating (dividing by out-of-atmosphere signal) Vertical distribution retrieved by onion peeling method

11 Ozone retrieval VISION scientific goal 1: polar and mid-latitude stratospheric ozone vertical profiles Absorption increases when looking deeper in the atmosphere (smaller tangent heights) Ozone retrieved from the Chappuis band (~600 nm) Measurement at 3 (or more) Target: 5 % accuracy, 1 km vertical resolution, over the stratosphere O

12 Temperature retrieval VISION scientific goal 2: mesosphere and stratosphere temperature profiles Method 1: shape of the Sun (refractive flattening) [refractive index depends on t ] Courtesy of NASA NASA

13 Temperature retrieval VISION scientific goal 2: mesosphere and stratosphere temperature profiles Method 2 - Sun light dilution ARID method [Fussen et al., AMTD., 8, , doi: /amtd , 2015] Courtesy of NASA 2 K accuracy below 72 km

14 VISION instrument, VTT (Finland) VISION stands for Visible Spectral Imager for Occultation and Nightglow Spectral imager similar to the Aalto-1 Spectral Imager (AaSI) (Fabry-Perot interferometer + CMOS array sensor) Field of view: 2.5 Dimensions 97x97x50 mm, mass 500 g Power < 3 W Filter module Electronics module Image sensor module FPI control Heater control Main electronics Heater Collimating optics module FPI module Focusing optics module Main housing

15 Spectral transmission Fabry-Perot interferometer principle Fabry-Perot Mirrors Incoming light Wavelength/[nm] Transmitted light Air gap Fabry-Perot + spectral filters: up to 3 modes Tuneable air gap: piezo actuator Range: ~ nm, FWHM: < 10 nm Detector: commercial CMOS 2048x2048 RGB

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17 Retrieving 3 wavelengths from RGB

18 Data downlink S-band for data transmission downlink capacity (52 MB/day) (SLP+VISION) 10 snapshots/s, 31 occultations/day > 8 GB/day O 3 & t ARID : only total intensity ( px) Sun shape: 5 image moments [upon request, rows & col. 880 values] Courtesy of NASA other benefits of imager: o ensure Sun entirely in the FOV o assess ADCS pointing accuracy o possible coupling with ADCS

19 SLP stands for Sweeping Langmuir Probe SLP scientific objectives ESA-ATG Medialab SLP scientific objectives are the in-situ study of: 1. the ionosphere-plasmasphere coupling 2. the sub-auroral ionosphere and corresponding magnetospheric features 3. the aurora structure

20 Principle 4 cylindrical Langmuir probes (at the edge of solar panels) electrical potential periodically swept with respect to the plasma potential from electric current collected by each probe, retrieval of: local electron density and t local ion density spacecraft potential SLP instrument (built by BISA) up to 50 sweeps/sec high spatial resolution (150 m) power consumption: 1.7 W mass: 150 g envelope electronic boards: 91x95x35 mm boom + probe: 80 mm outside solar panel

21 Orbit high inclination polar regions (SLP) all latitudes (VISION) altitude ~550 km duration 2 years at least life time < 25 years (debris mitigation) period ~94 min. 31 occultations/day (SS & SR)

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23 BISA Partners and sponsors Consortium (STCE)

24 Spare slides

25 Parameter Nominal value Remarks Field of View (FoV) 2.5 x 2.5 The S/C must ensure that the Sun is maintained inside that FoV during the event duration. Pixel FoV ² Target wavelength range Mandatory wavelength range nm nm Mandatory spectral resolution < 10 nm@fwhm Over the whole wavelength range Spectral resolution target Detector resolution (RGB pixels) < 5 nm@fwhm 2048x2048 Spectral image size (in pixel) 1024x1024 A set of R, G1, G2 and B pixels reduces to one spectral pixel Dynamic range Operational temperature 16 bits [-25 C ; +30 C] Life time and robustness 2 years VISION should be sized for 2 years of lifetime Amount of snapshots 2 x 10 7 Temperature cycles Working hours 600 Mass Peak power consumption Average power consumption when switched on <700 g < 8 W < 4 W Orbit averaged power 0.2 W Data processing power excluded Dimensions (mm) 50x95x95 Will fit in half a cube. Lens aperture 15 mm Picture size 8 MB 2048 x 2048 x2 bytes

26 Short historical review Spring 2009: concept starts within QB50 frame Spring 2010: contacts with VTT Finland Summer 2011: funding by Belgian National Lottery 2012: beginning of the build-up of the solution from the bottom-up 2013: BELSPO involvement in CubeSats Iterations and convergence on the technical solution Public call for the platform Clyde-Space is selected. Delivery: Oct : ESA Call (June), Proposal (July, including a description of the technical solution) Negotiation (Oct) Contract (Nov) Kick-off (Oct), progress meeting 1 (Dec) 2015: Independence from QB50 (March) Radiation tests (PLC and SLP, April) Preliminary design review (April)

27 Project overview PICASSO: PICo-Satellite for Atmospheric and Space Science Observations End-to-end in-orbit demonstration (IOD) mission, CubeSat Technology Pre-Developments ESA Contract N /14/NL/MH GSTP and TRP Total duration: 29 months Main scientific objectives: Atmospheric Ozone and T vertical profile retrieval Local electron density and temperature Avionics: 3U CubeSat with Performant ADCS S-Band for scientific data downlink Star tracker & GPS 4 deployable solar panels and all the rest Payload: VISION: a miniaturized tuneable hyper-spectral imager in the visible SLP: a 4-needle Langmuir probes whose electric potential is swept Powerful dedicated computer for data onboard processing

28 Roles BISA (prime): Management All scientific aspects (including inflight scenario definition and data analysis) VISION data processing software SLP Launch Platform (in-kind contribution, subcontracted to Clyde-Space) CSL: Technical coordination / follow-up Verification of the interfaces PA/QA Clyde-Space: Mission Design Integration of the payload Integrated spacecraft functional and environmental testing Operations (in-kind contribution, incl. the ground-station) VTT: VISION hardware

29 Initial planning (summary) PICASSO and SIMBA (RMI) divorced from QB50 in Jan Looking now for a commercial flight in Q3-Q4/2016 (and for extra funding 200 k )

30 Some new kind of remote sensing measurements with a spectral imager