A private mission to Mars, backed by a billionaire and NASA science, is aiming for a 2028 launch—if its untested rocket is ready.
Relativity Space, a launch vehicle developer that has not yet reached orbit, announced plans on June 17, 2026, to build and launch a Mars science orbiter in 2028. The mission, designated Aeolus, will operate under a newly established Interplanetary Sciences Program and carries a payload suite from NASA's Ames Research Center. The company has been selected by NASA to provide the spacecraft, launch vehicle, and cruise operations under a public-private partnership model.
Mission Overview
The orbiter is scheduled for launch in late 2028 aboard Relativity Space's Terran R reusable rocket, coinciding with a favorable Earth-to-Mars transfer window. If the rocket is not ready for this window, the mission would be delayed to the next opportunity in 2030 or 2031.
The spacecraft will carry two primary scientific payloads:
- An atmospheric profiling instrument suite (named Aeolus) consisting of four instruments from NASA's Ames Research Center to study Martian winds, temperatures, dust, and clouds.
- A radar instrument to map subsurface ice and geology.
The orbiter is also designed to provide communications relay services for surface assets using laser and radio-frequency links, potentially addressing the aging NASA Mars relay fleet (Mars Reconnaissance Orbiter, MAVEN, Odyssey), which has no committed replacement.
Relativity Space stated the spacecraft will include "massive" data storage and "server-class compute" capabilities for artificial intelligence and autonomous operations.
Contractual and Funding Details
NASA selected Relativity Space to build, launch, and deliver the spacecraft under a six-year reimbursable Space Act Agreement. Under this arrangement, NASA will supply the scientific instruments and handle data processing, while Relativity Space will construct, own, and operate the spacecraft. The contract value was not disclosed.
The mission is supported by an undisclosed philanthropic organization, according to a source familiar with the plans. Relativity Space declined to name the donor. The company stated that all scientific data collected will be released publicly. Questions regarding control of communications relay scheduling and dependency on privately owned infrastructure were not addressed.
Company Background
Relativity Space previously developed the Terran 1 small launch vehicle, which flew once on March 23, 2023. The rocket passed max-q but lost its upper stage and did not reach orbit. The company subsequently retired Terran 1 to focus on the larger, reusable Terran R.
Terran R is a medium-class reusable launch vehicle comparable to SpaceX's Falcon 9, with its first flight scheduled for late 2026 from Cape Canaveral. Industry sources have reported an expected delay to 2027.
Former Google CEO Eric Schmidt joined Relativity Space as CEO in March 2025, succeeding co-founder Tim Ellis, and made a significant personal investment in the company. Schmidt's philanthropic vehicle, Schmidt Sciences (founded by Eric and Wendy Schmidt), previously announced the Lazuli space telescope in January, targeting a 2028 launch on Terran R. Whether Schmidt Sciences is the specific backer of the Mars orbiter mission is unconfirmed.
Previous Plans
Relativity Space announced a separate Mars lander mission with Impulse Space in 2022, initially targeting a 2024 launch window that was later pushed to 2026. No recent updates on this mission have been provided.