The title is incorrect on two accounts. 1) We've witnessed geomagnetic storming with many other probes, but never had multiple spacecraft separated on the spatial scale of the electron diffusion region (several to 10's of km's). Since this region where magnetic reconnection occurs is so small and spacecraft travel fast, you also need extremely fast temporal resolution to make worthwhile observations. 2) (this one is much more minor) Ever since MMS was launched, the sun has been relatively quiet. Solar Cycle 24 has been a total let down; the peak of activity was almost a factor of two lower than what model-based predictions were saying several years ago. Reconnection is a commonly occurring process, it only requires that the Interplanetary Magnetic Field (IMF) have a southward component.
Anyone with journal access can check out the Science write-up.
OK, after reading it twice more I have still a lot of details to research, but what intrigues me most is the configuration of probes. If distance is crucial and having at least four (I'm assuming that it's for similar relativistic reason why GPS works only if you have 4 satellites), why are they not arranging fifth one in the centre of mass of that tetrahedron? I don't need to study crystallography to know that it minimizes distance and massively improves probability of having at least four in the reconnection zone. Is there any reason other than sheer price of these satellites that would prohibit it?
Yup, cost. Obviously, four is the bare minimum for doing instantaneous 3D imaging. These events are chaotic enough that no two fly-throughs are exactly the same, so extrapolating the physics using data from multiple instances of three spacecraft in the reconnection region isn't nearly as helpful as having four in the region simultaneously. Also, the geometry of the tetrahedron in relation to the reconnection geometry changes over time as the orbit precesses, requiring another degree of correction. The poor souls in the operations center up at LASP aren't going to like the principal investigator's latest request to take the distance between satellites down to 5 km. Obviously, the probability of a collision is greatly increased, so it will require extra attention to station keeping ($$$'s).
SPEDAS is kind of a disaster. It runs on IDL, proprietary software, with licenses costing around $800, or $100 for a student license. It also breaks on a bi-weekly basis. You have to go re-download the latest version of the library to make it run again. IDL might be my favorite language to write in, as it's what I started with, but free is nice, and Python libraries are growing at a faster rate. I haven't had this problem. If you need me to send you a screen shot of a figure, I think I could do that. Take your time digesting this, you're making me look bad! HahahI need to flip pictures to negative just to know wtf is there
Though scipy is kind of a mixed bag. I don't know about the physics packages, but totally incorrect code copy/pasted from some student's blog finds its way into the machine learning packages often enough that I'm never comfortable using them without going over them with a fine toothed comb anymore.