The stars call to us, as Carl Sagan once said. Given the human drive to explore our world and expand our reach, it is likely only a matter of time before we begin to build our homes in the solar system. The moon and Mars could be acceptable destinations, but nearby asteroids could also become homes, as a recent study shows.

The cold, weightless, radiation-filled dark of space poses a number of challenges to human habitation. We must be shielded from cosmic radiation and solar wind, and microgravity poses significant health hazards to the human body. This will force us to live under a layer of regolith or soil on the moon and Mars. Given the low gravity of these worlds, we might be better off living deep within small asteroids that we can spin up to create a healthy artificial weight.

Since July 2022, a miniature satellite about the size of a shoebox has been orbiting Earth and monitoring how much solar energy reaches the atmosphere. Now, scientists are finalizing their analysis of the first five months of measurements it gathered while in orbit.

The sun is by far the largest source of energy to Earth, dwarfing the energy generated by Earth's core, and it plays a major role in global climate. Precise and accurate measurement of how much solar energy is absorbed by Earth—Total Solar Irradiance (TSI)—is crucial to our understanding of Earth's climate system.

The CubeSat, called the Compact Total Irradiance Monitor-Flight Demonstration, or CTIM-FD, is on a one-year mission to develop and test new technologies for measuring TSI.

CTIM-FD was designed and built by the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder and the National Institute of Standards and Technology (NIST).

A key part of this mission is to directly compare the measurements of CTIM against its larger counterparts to demonstrate that it can perform measurements just as precisely and accurately.