NASA Reserves Science Payload Space for Mars Telecommunications Mission – SpaceNews

NASA is reserving a small amount of space on a Mars telecommunications spacecraft for science payloads, potentially including one or more CubeSats, as part of its Mars Telecommunications Network (MTN) mission. The decision marks a shift from earlier plans that focused solely on communications and navigation services for Mars-based assets through 2035.

The MTN mission, funded by a $700 million allocation from the 2025 budget reconciliation bill, aims to provide robust, continuous communications and positioning, navigation and timing (PNT) services for spacecraft operating at Mars through 2035. NASA requires the spacecraft to be “delivered to the Administration” by the end of 2028, though the bill does not explicitly mandate a launch by that date.

In slides from an April 9 industry day about the mission, published by NASA on a procurement website on April 24, the agency announced it was adding a requirement to support a small science payload. Under this updated requirement, the mission must accommodate a science payload weighing up to 20 kilograms in a volume of 55 by 55 by 45 centimeters. The payload would consume up to 60 watts of power and generate between 200 and 1,000 megabits of data per day.

NASA will provide the science payload, and all payloads will be negotiated with the NASA team to ensure they do not impact the MTN schedule requirements. The agency noted that the payload could include CubeSats, stating in the presentation: “There is consideration for deploying free-flying CubeSat payloads in Mars orbit.”

Louise Prockter, director of NASA’s planetary science division, confirmed during an April 21 meeting of the Mars Exploration Program Analysis Group that discussions are underway regarding potential science instruments or CubeSats for the mission. She noted that NASA is evaluating options given the limited size, weight, and power available for the payload.

The MTN spacecraft is being developed primarily as a communications relay rather than a science mission. Its core objectives include returning data from surface missions, providing navigation support, and ensuring reliable communications during critical entry, descent, and landing operations. The spacecraft is expected to operate through at least 2035, gradually replacing aging assets that currently handle most of the relay workload around Mars.

While the draft request for proposals issued on April 2 did not initially include any mention of science roles, the updated requirements reflect NASA leadership’s commitment to include science on every mission where feasible. The agency has not yet disclosed what specific science instruments or CubeSats it is considering for the payload, nor how it will select and fund the science component.

Rocket Lab has proposed a dedicated Mars Telecommunications Orbiter (MTO) for the MTN mission, featuring laser communications and an areosynchronous orbit architecture. The company states its design aims to meet NASA’s requirements while alleviating pressure on deep space relay infrastructure. NASA’s Mars Telecommunications Network is distinct from traditional Mars orbiters in that it is being developed primarily for communications and navigation rather than scientific investigation.

Some scientists had advocated for incorporating science instruments on the orbiter, but others noted that schedule and budget constraints likely would not allow for significant science additions. The updated payload accommodation represents a compromise that enables limited science participation without jeopardizing the mission’s primary communications and navigation objectives or its 2028 delivery deadline.