1 Kuafu A mission to start a mission William Liu Canadian Space Agency & Chinese Academy of Sciences August 29, 2011, 3rd ILWS Science Symposium, Beijing

2 KUAFU IN A FEW WORDS Same principles and equations Different boundary conditions Different solution

3 Solar Energy Output I = X Magnetic field complexity results in reconnection and particle ejection in the solar corona, X

4 Solar energy input II = Y Magnetic complexity also results in electromagnetic radiation (flares), Y

5 Solar wind at 1 AU = Z X (primarily) leads to a variable solar wind at 1 AU, Z

6 Magnetopause interaction = W Credit: University of Michigan Solar wind condition Z leads to variable interaction with the magnetosphere at the magneto- pause, W

7 Credit: University of Alberta Energy deposition = U Energy created through W is dissipated in the ionosphere

8 Systems Question Before, missions were focused on X, Y, Z, W, U, etc. individually The System Question below is of great interest but seldom simultaneously observed. U = F 1 (W,Y) W = F 2 (Z, U) (feedback, cf., potential saturation) Z = F 3 (X) F i is some time integral over the independent arguments

9 Kuafu A at the first Lagrangian point Kuafu B in double Molnya orbit with 6 Re apogee K-A imaging observation of X and Y K-A in-situ observation of Z K-B imaging observation of U K-B in-situ observation of W Kuafu: System science discoverer 24/7 simultaneous imaging supported by high-resolution in-situ observation focused on kinetic-to-MHD scale physics

10 Kuafu A Imaging Lyman-  imaging of solar disk Lyman-  + whitelight inner coronagraph Whitelight outer coronagraph Essential objective is to observe the entire sequence of solar wind acceleration, with special focus on the transition region

11 Generation of fast, slow solar wind & CME Deepen the knowledge of energy transport process between the photosphere and corona; improve the predictability of solar eruptive events –What is the relationship between CMEs and motions and magnetic field structures at the surface? –What is the relationship between the energy carried by CMEs and surface features? –How are CMEs and other solar wind structures accelerated? –What is the directionality of CMEs? –What is the short-term variability of total solar-irradiance?

12 Kuafu B Imaging

13 Auroral Complexity The morphology of U exhibits a high degree of complexity Vortices Arcs Turbulence

14 12-h Molnya orbit Stationarity and corotation with respect to a fixed point on Earth Year 0: long hover in the cusp 63  inclination and 6 earth radii apogee Long dwell time over ground networks on Earth Year 0.5: long hover over the nightside aurora region

15 Kuafu spacecraft 图五夸父  卫星 示意图 Kuafu A –3-axis stabilized satellite at L1 –Total mass 722 kg –Payload 130 kg –Power: SOM 906 W; EOM 752 W –Downlink telemetry 350kpbs. Kuafu B (anticipated) –Two 3-axis stabilized satellites in 12-h Molnya orbit –Mass: 1200 kg per satellite –Science payload ~65 kg per satellite –Power: ~80 W for science payload, 1 kW overall, per satellite –Downlink: ~ 2Mpbs.

16 WHAT NEW BOUNDARY CONDITION Canadian Space Agency cannot confirm anticipated participation in Kuafu at this time (despite great interest) due to government austerity measures European national agencies cannot provide the majority of Kuafu instruments as originally planned Chinese Academy of Sciences insists that Kuafu be a mission based on strong international collaboration

17 FIND NEW SOLUTION The international situation argues for –Launch Kuafu A first (by 2016), with an enhanced in-situ instrumentation from international sources –Start immediately with a collaborative framework committed to launching Kuafu B+ by 2019 –Search interim international collaborations with concurrent missions (MMS, SWARM) This is riskier than we like, but the risk should be balanced against the consequence of no Kuafu –Certainty of failure is not better than possibility of success A sure winner –Rename the mission iPhone 6.

18 Strawman Payload Lyman-  disk imager Lyman-  + WL inner coronagraph WL outer coronagrah Fluxgate magnetometer Medium-energy ion and electron analyzer (0.1 – 30 keV) High-energy particle package Low-energy ion and electron imaging spectrometers ( eV) Induction magnetometers Radio-burst instrument Hard-X ray spectrometer Solar irradiance measurements UV LBH-band imager –Band-split for flux and average energy determination –Day glow suppression for true global imaging Fluxgate and induction magnetometers Low-energy ion and electron imaging spectrometers (<100 eV) Medium-energy ion and electron analyzer (0.1 – 10 keV) High-energy electron telescope Options

19 A MORE BALANCED KUAFU Simplified imaging –Still maintain the innovation of Lyman-  coronagraphy and tracking of CMEs to 20+ solar radii Enhanced in-situ measurement –Better measurement of the solar wind on the sub- MHD scales will yield better characterization of electromagnetic noises and its potential effect on geoeffectiveness (i.e., relationship to reconnection)

20 Conclusion An ambitious first attempt to observe and understand the causal chain and complexity in the Sun-Earth System, simultaneously and continuously. The challenge is to make it happen.