CASSIOPE

The commercial payload, named Cascade, is a technology demonstrator courier in the sky, aimed a providing a proof of concept for a digital broadband courier service for commercial use. Built by MDA, the operational concept is to receive very large data files as the satellite orbits the globe, store them onboard temporarily, then deliver them at a later time to nearly any destination worldwide.[11]

The demonstrator will provide a secure digital store-and-forward file delivery service, exploiting the fact that CASSIOPE passes over much of the globe 15 times per day. It has been described as a courier service, with the customers using a small parabolic antenna of one or two meters (three or six feet) to upload or download files at a rate of 1.2 gigabits per second. The storage capacity will be between 50 and 500 gigabytes and the data delivery time will be about 90 minutes, depending on the pickup and deposit points on the globe.

The e-POP portion of CASSIOPE is a suite of eight scientific instruments. The University of Calgary's Institute for Space Research leads the science project, while MDA is the prime contractor for the mission including launch and operation of the spacecraft. The orbital science mission is scheduled for a 21-month duration.[9]

e-POP will gather data on Solar storms in the upper atmosphere. These storms give rise to the polar aurora or northern lights seen in the skies in northern latitudes. While these atmospheric glows may offer a thrilling night time spectacle, the inducing radiation can interfere with radio communications, GPS navigation, and other space-based systems. The eight scientific instruments aboard CASSIOPE will help scientists understand solar weather and eventually plan for measures to mitigate its deleterious effects.[8]

The e-POP payload contains eight scientific instruments:[12]

• Coherent EM Radio Tomography (CER), measuring radio propagation and ionospheric scintillation
• Fast Auroral Imager (FAI), measuring large-scale auroral emissions
• GPS Altitude and Profiling Experiment (GAP), high-precision position and attitude determination
• Imaging and Rapid Scanning Ion Mass Spectrometer (IRM), measuring the three-dimensional distribution of ions
• Fluxgate Magnetometer (MGF), high-precision magnetic field perturbation measurement
• Neutral Mass Spectrometer (NMS), measuring the mass, composition and velocity of neutral particles
• Radio Receiver Instrument (RRI), measuring radio wave propagation
• Suprathermal Electron Imager (SEI), measuring low-energy electron distribution

After the second stage separated from the booster stage, SpaceX conducted a novel flight test where the booster conducted a test to attempt to reenter the lower atmosphere in a controlled manner and decelerate to a simulated over-water landing.[19] The test was successful, but the booster stage was not recovered.

After the three-minute boost phase of September 29, 2013 launch, the booster stage attitude was reversed, and three of the nine engines refired at high altitude, as planned, to initiate the deceleration and controlled descent trajectory to the surface of the ocean. The first phase of the test worked well and the first stage re-entered safely.[13]

However, the first stage began to roll due to aerodynamic forces during the descent through the atmosphere, and the roll rate exceeded the capabilities of the booster attitude control system (ACS) to null it out. The fuel in the tanks centrifuged to the outside of the tank and the single engine involved in the low-altitude deceleration maneuver shut down. Debris from the first stage was subsequently retrieved from the ocean.[13]

SpaceX also ran a post-mission test on the second stage. While a number of the new capabilities were successfully tested on the September 29, 2013, CASSIOPE flight, there was an issue with the second stage restart test. The test to reignite the second stage Merlin 1D vacuum engine once the rocket had deployed its primary payload (CASSIOPE) and all of its nanosat secondary payloads was unsuccessful.[10] The engine failed to restart while the second stage was coasting in low Earth orbit.

Five nanosatellite spacecraft that were also carried to orbit on the same launch vehicle that carried the CASSIOPE primary payload:[11]

• CUSat, Cornell University
• Drag and Atmospheric Neutral Density Explorer (DANDE), University of Colorado Boulder
• three Polar Orbiting Passive Atmospheric Calibration Spheres (POPACS), each a 10 cm (4 in) white aluminum sphere, joint project of Morehead State University, University of Arkansas, Montana State University, Drexel University, and Planetary Systems Corporation.[20]