DYNAMIC IONOSPHERE CUBESAT EXPERIMENT

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1 Geoff Crowley, Charles Swenson, Chad Fish, Aroh Barjatya, Irfan Azeem, Gary Bust, Fabiano Rodrigues, Miguel Larsen, & USU Student Team DYNAMIC IONOSPHERE CUBESAT EXPERIMENT NSF-Funded Dual-satellite Space Weather Mission Project Funded October 2009 Launch October

2 Dynamic Ionosphere Cubesat Experiment SCIENCE MOTIVATION IONOSPHERE SCIENCE November 20, 2003 storm 50 October storm 50 Plume Bulge LT LT Horizontal distribution of peak electron density from ASTRA s 4D assimilation 2

3 SCIENCE OBJECTIVES 1. Investigate the physical processes responsible for formation of the geomagnetic Storm Enhanced Density (SED) Bulge 2. Investigate the physical processes responsible for the formation of the SED Plume at the base of the SED Bulge and transport of high density SED plume across the polar region 3. Investigate the relationship between the penetration electric fields and the formation and evolution of SED LT Plume Bulge 3

4 SCIENCE REQUIREMENTS Sun-synchronous orbit in the 12-16LT range is ideal Measure Electron Density Measure E-fields (plasma drift) Time-resolution of the measurements matches the scale-size of the features to be observed 7km/s = 14 s; cadence of 0.5 to 1 seconds for the plasma and electric field measurements) AC electric field spectrum measurements (to capture irregularities) Expect 1 SED per month 6-mo mission yields 6 SED events Two 1.5U ( cm) CubeSats Common high-inclination pearls-on-a-string orbit. The two satellites will remain within ~300 km of one another for up to six months, allowing temporal-spatial deconvolution Each satellite will carry identical instrumentation 4

5 INSTRUMENTATION Electric Field ~0.2 mv/m Double Probe Technique 5 m wire booms ~70 Hz sample rate Plasma Density ~10 2 cm -3 Dual Langmuir Probes ~70 Hz sample rate Magnetic Field ~5 nt 3 axis Magnetometer ~70 Hz sample rate 5

6 DICE SPACECRAFT Pumpkin C&DH System SDL/USU Science board L3 Radio 1.5 Mbit/s down link Sun sensor + Magnetometer 0.1º Post flight Power ~1.5 W spacecraft ~200 mw payload Instrument Electronics ADCS Board with GPS Module Z-axis Torque coil C&DH Board with Processor EPS and Battery Board Comm Board with L3 Radio 6

7 L3 CADET RADIO Custom designed high-speed downlink UHF radio Designed and built by L3 communication Tested and debugged by L3 and SDL engineers 1.5 Mb/s downlink (designed for up to 24 Mb/s) 7

8 MISSION Two spinning spacecraft Leader follower 102º Inclination km Alt Circularize ~ 12 yr 90 day mission Goal 6 mo F15, 21:12 LT F16, 20:03 LT F14, 19:26 LT F13, 18:28 LT F17, 17:36 LT DICE will measure SED plasma density and E- fields in key afternoon sector. 8

9 MISSION CONOPS Detumble, Align Spinup, Initial Contact Wire Boom Deploy On-orbit Operations (up to 5 years) Initial Deploy Launch Disposal Integration Backup Primary

10 DICE ORBIT LIFE TIME & Telemetry contact Dice on orbit collection rates High rate 11 kbits/s Low rate 4.5 kbits/s DICE Simulated with STK Lifetime 12 years Contacts with Wallops Required 0.8% High data rate collect 0.4% Low data rate collect Significant Margin Higher orbit than conceived Wallops and SRI ground stations Requirement Level 10

11 DICE INTEGRATION AND TEST Thermal Testing Systems Integration

12 E FIELD INSTRUMENT Four deployable booms with metallic spheres 12

13 BOOM DEPLOYMENT Sphere Sphere

14 DICE TESTING AT WALLOPS

15 WALLOPS ANTENNA AND LINK BUDGET TESTING Testing of All DICE RF and ground station components consistent with link budget DICE spacecraft commanded through 450 MHz Cadet Radio Uplink Horizontal polarization at 465 MHz Vertical polarization at 465 MHz

16 Stage 4 Completed and submitted to NSF Licensing and DICE Status Certification at NTIA 8/11/11 License expected 2 wks later Informal Discussions with NTIA Seemed Positive 16

17 DICE Timeline and Status NSF funding started 10/1/09 Student team assembled (12 located at SDL) Design and Team conference calls - weekly Science, Mission and Software requirements completed PDR Design Review 1/25/10 CDR May 20, 2010 Satellite and instrument construction complete Deployables tested, instruments tested L3 radio fully functional Mission Readiness Review July 20, 2011 In progress: Final thermal/shake tests, calibration In progress: Radio licensing spectrum allocation through NSF Spacecraft delivery to NASA for Integration Sept 2011 Launch October

18 DICE STUDENT TEAM 12 Students and ~5 Professionals 18

19 19

20 BACKUP SLIDES 20

21 DICE SPACECRAFT (LAUNCH WITH NPP) DICE: 824 x 350 km 102º Inc orbit with a 10:30 local-time descending node. 10 m tip-tip

22 SUB-SYSTEM STATUS Sub-system %Complete How Verified C&DH/OS 100 Thermal functional testing EPS 100 Thermal functional testing Science 95 (mag & spectrometer channels calibration) Thermal functional testing Comm/Antennas 100 Thermal functional testing, Radar range testing, Pattern measurement characterization Thermal 100 Analysis, Thermal functional testing Structural 100 Analysis, Assembly Mechanisms 100 Thermal functional testing ADCS 90 Flatsat functional testing