Only a few years ago, the astronomy and heliophysics communities were skeptical about whether CubeSats could reliably obtain scientific data. But these breadloaf-size satellites have proven their ability to return useful data. During the APS April Meeting 2019, Christopher S. Moore will describe how the twin Miniature X-ray Solar Spectometer CubeSats measure soft X-rays from the Sun. These were the first solar science-oriented CubeSat missions flown for the NASA Science Mission Directorate. This image shows Christopher S. Moore holding the MinXSS CubeSat.