Radiation Belt Storm Probes Van Allen Probes Launched

Radiation Belt Storm Probes (Van Allen Probes) Launched 30 August 2012 Movie courtesy of NASA

Van Allen Probes Science Objectives, Instruments, & Data Brett Anderson Dartmouth College 16 June 2013 GEM Student Tutorial Artistic rendering courtesy of NASA

Radiation Belt Storm Probes (RBSP) Launched: 30 August 2012 4: 05 am EDT Cape Canaveral, FL Atlas V Rocket Renamed: 9 November 2012 Van Allen Probes

Van Allen Probes Orbit Information • • • Identical spacecraft Equatorial orbit Perigee: ~1. 1 RE Apogee: ~5. 8 RE 9 hour period Complete MLT coverage over whole mission Spin stabilized, ~5 RPM Spin axis towards sun One satellite laps the other every ~75 days for simultaneous observations over a range of spacecraft separations Expected lifetime: 2014 – 2015 THEMIS RBSP

Van Allen Probes Science Objectives • Discover which processes, singly or in combination, accelerate and transport radiation belt electrons and ions and under what conditions. • Understand quantify the loss of radiation belt electrons and determine the balance between competing acceleration and loss processes. • Understand how the radiation belts change in the context of geomagnetic storms.

Van Allen Probes What measurements are made? • Particles & Plasma - Electrons + Protons & Ions • Fields • Magnetic • Electric • Waves The Van Allen Probes have the best instrumentation to be launched into the heart of the radiation belts, ever! • Detection sensitivity • Energy resolution • Temporal sampling cadence Two spacecraft are better than one! Especially since their separation distance varies! Artistic rendering courtesy of NASA

Particles & Fields • Van Allen Probes Instrumentation Particles & Plasma Energetic Particle, Composition, and Thermal Plasma Suite (ECT) – Dr. Harlan Spence, The University of New Hampshire • RBSP Ion Composition Experiment (RBSPICE) – Dr. Louis Lanzerotti, The New Jersey Institute of Technology • Relativistic Proton Spectrometer (RPS) – Dr. David Byers, National Reconnaissance Office (*not pictured) – Dr. Joseph Mazur, Aerospace Corporation (at left) Fields Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) – Dr. Craig Kletzing, The University of Iowa Electric Field and Waves Suite (EFW) – Dr. John Wygant, The University of Minnesota Assembly and Operation Johns Hopkins University — Applied Physics Laboratory (JHU-APL)

Particles & Fields Diagram courtesy of NASA

FIELDS (Electric and Magnetic Field Instrument Suite and Integrated Science) EMFISIS Data Whistler-mode Chorus Waves Frequency k. Hz Burst Mode = High time resolution! Color: Wave Power Waveform Whistler-mode Chorus is capable of: Accelerating AND Depleting radiation belt electrons! (microburst precipitation) Figure courtesy of Craig Kletzing

Particles & Fields Diagram courtesy of NASA

FIELDS (Electric Field and Waves) EFW Data Low frequency electric fields Data: Ex from RBSP-B and RBSP-A on October 13, 2012 Two Spacecraft! Slightly different orbits separation ~1/3 of orbit > 5 -hours Ex (m. V/m) = Better Spatial & Spacecraft Temporal Resolution! Perigees Low frequency waves at outer edge of radiation belts might be responsible for rapidly accelerating electrons! Also…for depleting electrons! Ex (m. V/m) UT 00 04 13 October 2012 08 12 16 20 00 Figure courtesy of Craig Kletzing

Particles & Fields Diagram courtesy of NASA

(Energetic Particle, Composition, and Thermal Plasma Suite) Particles ECT Data Relativistic Electron Proton Telescope (REPT) 4. 5 Me. V 6 5 Color = Flux L* 4 3 2 1 31 August 2012 16 October 2012 Meridional Projection of REPT Electron Flux Video courtesy of LASP

Particles (Energetic Particle, Composition, and Thermal Plasma Suite) ECT Data Relativistic Electron Proton Telescope (REPT) 4. 5 Me. V Interplanetary Shock Waves Baker et al. , 2013

Van Allen Probes • The Van Allen Radiation Belts are highly dynamic! • With the Van Allen Probes, we are beginning to see much more detailed structure and behavior! • We still don’t know a lot about the radiation belts. • The Van Allen Probes have the best instrumentation to be launched into the heart of the radiation belts, ever! • So, there’s LOTS of data to be looked at, LOTS of science results to be discovered, and lots to be learned about the radiation belts.

Particles Mission of Opportunity BARREL • Balloon Array for Radiation-belt Relativistic Electron Losses – P. I. Robyn Millan, Dartmouth College • Scientific Goals: – Determine total relativistic electron loss rates to atmosphere – Characterize spatial structure of precipitation – Determine relative importance of various types of precipitation • BARREL payloads measure bremsstrahlung x-rays at ~35 km, incident from “precipitating” radiation-belt relativistic electrons • The BARREL array of 5 -8 balloon-borne payloads simultaneously detects precipitating electrons over 8 -10 hours of MLT • Two Antarctic campaigns of 20 identical payloads, each – January 2013, completed – January 2014

Colorado Student Space Weather Experiment (CSSWE) P. I. Xinlin Li Launched: 13 September 2012 Last contact: 7 March 2013 Measures Electron & Proton Flux on a Low Earth Orbit 8 6 L 4 2 CSSWE OUTER RADIATION BELT Electrons RBSP

Fields & Particles Advertisement for Focus Group: Magnetic Field Mapping • Sessions in Salon D: – Monday at 10: 30 • Focus on “conjunctions” of Van Allen Probes and other experiments (THEMIS, BARREL balloons, CSSWE cube sat, ground-based data, etc…) – Monday at 1: 30 – Tuesday at 10: 30 • Focus Group Organizers: – Eric Donovan – Elizabeth Mac. Donald – Robyn Millan BARREL Payloads Image courtesy of Alexa Halford RBSP spacecraft Magnetic footprints L-shells

Check it out on the web!

Check it out on the web! http: //www. nasa. gov/vanallenprobes/ http: //vanallenprobes. jhuapl. edu/ http: //www. nasa. gov/mission_pages/rbsp/barrel/index. html

The End

Van Allen Probes Instrumentation • ECT – HOPE – Mag. EIS – REPT • • RBSPICE RPS EFW EMFISIS – Search-Coil magnetometer – Flux-Gate magnetometer Diagram courtesy of NASA

• Pictures of Pis • K&R figure of energy of particles in rad belts • EMFISIS Data slide: – KHz top plot vertical axis, color=“wave power” – No counts on lower plot vertical axis • EFW Data slide: – Take out all the facts at bottom, except UT. – Take out vertical axis labels – Point out when apogee, perigee, etc… • Point out which aspect of science objective, each data slide is dealing with.