Twin small spacecraft in space.

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 | 11:05 UTC
Launch Site Vandenberg Air Force Base, California, USA
Destination Mars
Type Flyby
Status Successful
Nation United States
Alternate Names MarCO


Demonstrate the ability of small satellites to explore deep space and provide real-time information in support of critical landing operations on a 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 launched with the InSight lander on an Atlas V rocket from Vandenberg Air Force Base, California. The MarCO twins and InSight were be navigated separately to Mars. The trio of spacecraft will arrive at Mars at the same time and the MarC) spacecrafts served as redundant communications relay of InSight’s entry, descent and landing data.


MarCO A and B successfully completed their mission as communications relay satellites for the InSight Mars landing on Nov. 26, 2018. The spacecraft will end up in orbit around the Sun.

View of Mars from MarCO spacecraft.
MarCO-B, one of the experimental Mars Cube One (MarCO) CubeSats, took this image of Mars from about 4,700 miles (6,000 kilometers) away during its flyby of the Red Planet on Nov. 26, 2018. Credit: NASA/JPL-Caltech

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

Related News