No one was hurt in yesterday’s SpaceX explosion, but among the items lost were a pair of Microsoft’s HoloLens augmented reality headsets.

The two headsets were loaded onto the intergalactic vessel alongside food and other supplies, ultimately headed to the International Space Station–but they never made it.

The ship blew up just minutes into the trip, with the HoloLens units and other supplies burning up upon re-entry into earth’s atmosphere.

Why were HoloLens headsets headed to the ISS in the first place? It’s not because the astronauts heard about Microsoft’s Halo HoloLens demo and wanted to try it. Rather, Microsoft and NASA are teaming up for a new project called Sidekick, in which astronauts use commercial technology to aid them on their missions.

Presumably, Microsoft will provide more HoloLens headsets for SpaceX’s next attempt.

According to SpaceX founder Elon Musk, the Falcon 9 ship failed due to an “overpressure event in the upper-stage liquid oxygen tank.” Unfortunately for SpaceX, after “several thousand” engineering hours of review, the company has yet to pinpoint a reason for the explosion.

For more on Microsoft’s Sidekick program with NASA, check out this blog post and the video below.