Towards Low-cost Swedish Planetary Missions

S. Barabash1, O. Norberg2, J.-E. Wahlund3, M. Yamauchi1, S. Grahn4, S. Persson4, and L. Blomberg5

1. Swedish Institute of Space Physics, Kiruna, SWEDEN2. Swedish Space Corporation, Esrange, SWEDEN3. Swedish Institute of Space Physics, Uppsala, SWEDEN4. Swedish Space Corporation, Solna, SWEDEN5. Royal Institute of Technology, Stockholm, SWEDEN

It is a fate for small countries like Sweden to seek low-cost high-performance missions in order to keep the cut-in-edge position in national level space missions.

Swedish Scientific Satellite Series

Swedish microsatellitesASTRID- 1World’s first ENA.

Total mass 27 kg

Stowed configuration

ENA main instrument seen on the left

1995

Swedish microsatellite ASTRID- 2”Complete Set” of

plasma instruments. Total mass 30 kg

In launch vehicle shroud

Clean-room testing at SSC, Solna

Sketch showing deployed axial magnetometer and star tracker boom

1998

Swedish nanosatelliteMUNIN

”Flying Instrument” Mass 6kg / 3 sensor

2000•MEDUSA•DINA•HiSCC

Nano-satellite advantage

* Technology: - Test of state-of-art satellite technology - Test of state-of-art instrument - Test of ordinary market components in space* Science: - Quick public science (space weather and auroral research) - Frontier science (with state-of-art instrument)* Educational Outreach

After performing both ends, Munin nanosatellite and Odin high precision satellite, it is natural to seek feasibility of low-cost interplanetary missions.

= Saga

Saga: interplanetary sub-satellite

Size: 50 50 40 cm (Astrid-2 type)Mass: 37 kg (9 kg payload) Power: 10 W

Subsystem massStructure including solar panel 6.0 kgAvionics unit 6.0 kgUHF communication system (assumed) 3.0 kgSun sensor 0.3 kgStar tracker 1.0 kgNutation damper 0.3 kgCable harness 1.3 kgBattery 2.0 kgThermal blanket 0.3 kgPropulsion system 2.5 kgPropellant 1.5 kgPayload 9.0 kgContingency & balance mass 4.2 kgTotal (Saga) 37.4 kg

Really 37 kg? Yes, as a sub-satellite!

Saga: Technical summaryAxis spin-stabilized, axis perpendicular to ecliptic Size 50x50x40cm boxMass 37 kg for sub-satellite + 4 kg for extra

communication package on mothershipPower 70 W from solar array (0.5x0.4m),

peak consumption 60 WPayload mass 9 kg, power 10 W Data link (+ranging?) Beagle-2 (MARESS) type UHF radio,

1-10 kb/sec with 40W powerSeparation & spin-up Mars Express (SUEM) type made by Hunting Main avionics simplified from SMART-1 (up to 40 kRad) Attitude/orbit control Cold gas (N2) propulsion + nutation damperAttitude determination sun sensor, star tracker

• Atmospheric evolution and solar wind induced atmospheric escape

• Instantaneous response of the near-planet environment (particle and electromagnetic) to solar wind variations

• Plasma processes near non-magnetized/magnetized bodies and structure of an induced magnetosphere

Saga: Plasma Science

Venus? Mars? Asteroid? Comet? Magnetotal?

Table 1: Saga proposed payload compared to Astrid-2

Instrument Saga Astrid-2 (10kg)DC Magnetometer dB < 0.1nT sameWave and E-field up to 16 MHz up to 2 kHzLagmuir probe x 2(density and temperature)

1~10^6 cm-3Vsc: ± 20V

same

Booms 1m x 2 + 10m x 4 3.3m x 4 + 0.8m x 2Ion mass spectrometer 0.01~40 keV, M/dM=5 Ion (no composition)Electron spectrometer 0.01~25keV sameEnergetic Neutral imager* 0.03-1keV, H , O, CO2 noX-ray detector* < 1keV noPhotometer* HI 1216, OI 1304 same*optional

Such a mission requires state-of-art technologies which must be tested in Earth-orbiting satellite.

Saga: Payload

Prisma + NanoSpace

Dual-S/C Technological Mission

Strategic position of Prisma/NanoSpace

Prisma77 kg including new kick motor

Payload 10.5 kgPower 26 WNew S/C technologyState-of-art Instrument

Prisma: Technology Test

* Semi-coordinated formation flightRanging by laserInter-satellite communication

* Micro-spacecraft technology Integration of electric componentKick motorHigh-telemetry (512 kbps)

* Flight test of new scientific instrumentation Miniaturization with high resolutionNew functionCommon bus

Prisma: PayloadInstrument function mass powerDC Magnetometer (*1) dB < 0.1nT 0.6 kg 2.0 WDC/AC Electric field (*2) DC ~ MHz 2.75 kg 4.2 WWave (*3) 1 Hz ~ 16 MHz 1.3 kg 7.4 WLangmuir probe x 2 1~106 cm-3, Vsc: ± 20V 0.55 kg 1.6 WIon mass + electron 0.01~25 keV, M/dM=5 1.6 kg 2.3 WEnergetic Neutral imager 0.03-1 keV, H, O, CO2 2.0 kg 2.0 WX-ray detector 5 ~ 40 keV, ∆E=1.5keV 0.3 kg 0.8 WGamma-ray detector HI 1216, OI 1304 0.5 kg 0.7 Wcommon electric box 0.95 kg 0.2 WPrisma Total 10.5 kg 21.2 W

Wave 0.2 kg 7 WDC Magnetometer 0.1 kg 2 WNanoSpace-1 Total 0.3 kg 9 Wbooms/wires: (*1) 1m x 2, (*2) 13m x 2, (*3) 1m x 6

1. Ionosphere-Magnetosphere (electrodynamic) coupling effects at ionospheric altitudes.

2. Plasma turbulence/structure and their role in plasma energization.

3. Atmosphere-Ionosphere coupling or physical processes behind sprites, gravity waves, and heatings.

4. Solar-Ionosphere coupling through plasma, radiation, and dynamics.

5. Oxygen and other heavy ion circulation from/to the ionosphere.

Science

Although this is a technological mission, Prisma will be the first ionospheric plasma mission with state-of-art instrumentation after 25 years' blank

Through Prisma mission, we try to* Keep cut-in-edge technology in micro-spacecraft body* Keep cut-in-edge technology in micro-spacecraft control* Keep cut-in-edge technology in scietific instrument

Concluding remarks

With Saga concept, we should be able to* Make planetary missions handy* Increase chance for international collaboration

Sweden always seeks international collaboration for aggressive missions