InSight is a robotic lander designed to study the interior of the planet Mars. The objective is to place a stationary lander equipped with a seismometer and heat transfer probe on the surface of Mars to study the planet's early geological evolution. This could bring new understanding of the Solar System's terrestrial planets — Mercury, Venus, Earth, Mars — and the Earth's Moon.

Mars Cube One (or MarCO) is a Mars flyby mission consisting of two nanospacecraft, of the 6U CubeSat format, that was launched alongside NASA's InSight Mars lander mission. Mars Cube One is intended to be a test of new miniaturized communications and navigation technologies. Should the two CubeSats make it all the way to Mars, they will be able to provide a real-time communications link to Earth for InSight during its entry, descent, and landing when InSight will be out of sight from the Earth. Mars Cube One is the first spacecraft built to the CubeSat form to operate beyond Earth orbit; besides telecommunications, they will also test CubeSats' endurance in deep space.