This illustration depicts a moment during the lander's descent when it is transmitting data in the UHF radio band, and the twin MarCO craft are receiving those transmissions while simultaneously relaying the data to Earth in a different radio band.

Launch Date May 5, 2018
Launch Site Vandenberg Air Force Base, California, USA
Destination Mars
Type Flyby
Status In Development
Nation United States
Alternate Names


Demonstrate the ability of small satellites to explore deep space and provide real-time information in support of critical landing operations on distant world.

MarCO, for Mars Cube One, will provide an experimental communications relay to inform Earth quickly about the landing. The two briefcase-size MarCO CubeSats will launch with the InSight lander on an Atlas V launch vehicle lifting off in March 2016 from Vandenberg Air Force Base, California. After launch, the MarCO twins and InSight will be navigated separately to Mars. The trio of spacecraft will arrive at Mars at the same time and the MarCo spacecrafts will serve as redundant communications relay of InSight’s entry, descent and landing data.

MarCO is a technology demonstration and not needed for InSight’s mission success.


This mission is in development.

Key Dates

May 5, 2018: Launch (with InSight lander)

Nov. 26, 2018: Mars Flyby / Relay Operations


Launch Vehicle: Atlas V

Spacecraft Mass:

The basic CubeSat unit is a box roughly 4 inches (10 centimeters) square. Larger CubeSats are multiples of that unit. MarCO's design is a six-unit CubeSat - about the size of a briefcase -- with a stowed size of about 14.4 inches (36.6 centimeters) by 9.5 inches (24.3 centimeters) by 4.6 inches (11.8 centimeters).

Spacecraft Instruments:

  1. UHF Radio Receiver

  2. X Band Radio Transmitter

Additional Resources

NASA Jet Propulsion Laboratory: Mars Cube One (MarCO)

Solar System News