We present the final design, environmental testing, and launch history of MiniCarb, a 6U CubeSat developed through a partnership between NASA Goddard Space Flight Center and Lawrence Livermore National Laboratory. MiniCarb’s science payload, developed at Goddard, was an occultation-viewing, passive laser heterodyne radiometer for observing methane, carbon dioxide, and water vapor in Earth’s atmosphere at ∼1.6 µm s −1 . MiniCarb’s satellite, developed at Livermore, implemented their CubeSat Next Generation Bus plug-and-play architecture to produce a modular platform that could be tailored to a range of science payloads. Following the launch on 5 December 2019, MiniCarb traveled to the International Space Station and was set into orbit on 1 February 2020 via Northrop Grumman’s Cygnus capsule which deployed MiniCarb with tipoff rotation of about 20° s −1 (significantly higher than the typical rate of 3° s −1 from prior CubeSats), from which the attitude control system was unable to recover resulting in a loss of power. In spite of this early failure, MiniCarb had many successes including rigorous environmental testing, successful deployment of its solar panels, and a successful test of the radio and communication through the Iridium network. This prior work and enticing cost (approximately $2 M for the satellite and $250 K for the payload) makes MiniCarb an ideal candidate for a low-cost and rapid rebuild as a single orbiter or constellation to globally observe key greenhouse gases.

We present a design for a 4 U (20 cm x 20 cm x 10 cm) occultation-viewing laser heterodyne radiometer (LHR) that measures methane (CH4), carbon dioxide (CO2) and water vapor (H2O) in the limb that is designed for deployment on a 6 U CubeSat. The LHR design collects sunlight that has undergone absorption by the trace gas and mixes it with a distributive feedback (DFB) laser centered at 1640 nm that scans across CO2, CH4, and H2O absorption features. Upper troposphere/lower stratosphere measurements of these gases provide key inputs to stratospheric circulation models: measuring stratospheric circulation and its variability is essential for projecting how climate change will affect stratospheric ozone.

The proposed Space-Based Telescopes for Actionable Refinement of Ephemeris (STARE) mission, which will consist of a constellation of nano-satellites in low Earth orbit (LEO), intends to refine orbits of satellites and space debris to less than 100 meters uncertainty in order to help satellite operators prevent collisions in space. To prove this is possible, a prototype STARE payload was used to refine the orbit of NORAD 27006 using a series of six ground-based images captured over a 60 hour period. The refined orbit, based on the first four observations made within the initial 24 hours allowed for prediction of the satellite’s trajectory to within less than 50 meters over the following 36 hours, as verified by the final two observations taken within that period. This paper describes the tools and methodology used to capture the images of NORAD 27006 and refine its orbit—the same ones that will be used during the STARE mission. The details of verifying the accuracy of the orbit over the next 36 hours are then presented, lending credence to the capability of STARE to accomplish its mission objectives.