Question 1

What is the Jervis Autonomy Module (JAM)?

Accepted Answer

JAM is an alternative positioning, navigation, and timing (Alt-PNT) solution developed by Rhea Space Activity that enables fully autonomous navigation without reliance on GNSS systems such as GPS. It uses passive optical sensing and onboard processing to determine a vehicle’s position, velocity, and trajectory across space and terrestrial environments.

Question 2

How does JAM navigate without GPS or GNSS?

Accepted Answer

JAM uses optical navigation techniques, capturing images of celestial objects such as the Moon, planets, asteroids, and satellites. By analyzing these observations, JAM determines its position relative to known reference points and generates precise state vector solutions, eliminating the need for GNSS signals or ground-based updates.

Question 3

What is altPNT and why is it important?

Accepted Answer

Alternative positioning, navigation, and timing (altPNT) refers to navigation solutions that operate independently of GNSS systems. altPNT is critical in environments where GNSS signals may be unavailable, degraded, jammed, or spoofed. JAM provides a resilient altPNT capability that ensures mission continuity in contested or denied environments.

Question 4

What makes JAM resistant to jamming and spoofing?

Accepted Answer

JAM relies exclusively on passive optical inputs rather than radio frequency (RF) signals. Because it does not depend on external transmissions, it is inherently immune to GNSS jamming and spoofing attacks, making it a highly secure and resilient navigation solution.

Question 5

What types of space craft or missions can use JAM?

Accepted Answer

JAM is designed to support a wide range of platforms, including spacecraft and satellites of various sizes/classes and autonomous systems. Its modular architecture allows it to scale from small satellites and drones to large, complex space missions, adapting to different operational requirements without additional infrastructure.

Question 6

Can JAM operate without ground control or communication?

Accepted Answer

Yes. JAM is designed for full autonomy and can provide navigation solutions, trajectory corrections, and orbital maneuver recommendations without requiring ground contact. This reduces latency, lowers operational costs, and enables missions in communication-constrained environments.

Question 7

How accurate is JAM compared to GPS?

Accepted Answer

JAM provides state vector outputs comparable to GNSS-based systems by leveraging precise optical measurements and onboard processing. While performance depends on mission parameters and environment, JAM is designed to deliver high-precision navigation suitable for mission-critical applications.

Question 8

What does PACE mean in relation to JAM?

Accepted Answer

PACE stands for Primary, Alternative, Contingent, and Emergency. JAM can function in all four roles: as a primary navigation system, a backup to GNSS, a contingency solution during disruptions, or an emergency fallback, ensuring continuous navigation capability across all mission phases.

Question 9

Is JAM only for space applications?

Accepted Answer

No. While JAM is optimized for space environments, its GNSS-independent navigation capabilities make it applicable to terrestrial and aerial systems operating in denied or degraded environments, including defense and autonomous vehicle applications.

Question 10

What are the advantages of optical navigation over traditional methods?

Accepted Answer

Optical navigation provides a passive, infrastructure-independent approach to determining position and trajectory. Unlike GNSS, it is not vulnerable to RF interference and does not require external signals, enabling greater resilience, autonomy, and operational flexibility.

Question 11

How does JAM improve mission resilience?

Accepted Answer

JAM enhances resilience by removing dependence on vulnerable external systems such as GNSS and ground control. Its autonomous operation, passive sensing, and PACE flexibility ensure that navigation capabilities remain intact even in contested, degraded, or communication-limited environments.

Question 12

Why is GNSS independence important for modern space missions?

Accepted Answer

GNSS signals are not always available in deep space and can be disrupted in contested environments. GNSS independence ensures that missions can continue operating reliably without external dependencies, which is critical for national security, deep space exploration, and autonomous operations.

Autonomous Navigation for Space Applications

Download the JAM data sheet and see how autonomous navigation performs across space, air, and ground domains.

Frequently asked questions