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About Spire


Spire Global's constellation is composed of LEMUR nanosatellites. Each satellite is multi-payload, equipped with different sensors to collect global radio frequency data in near-real-time.

This mission is considered a Third Party Mission Under Assessment. The evaluation will tackle cal/val activities and assess the products specifications. This analysis will be performed in the framework of the Earthnet Data Assessment Pilot (EDAP). The evaluation will also allow any interested user to investigate the suitability of the data for scientific and R&D activities.

Mission Parameters
Orbit Altitude500 km
Orbit Typesun-synchronous (the most) and equatorial
Orbit Inclination51.6°, 83°/85° and 37°
Orbit Period95 minutes
Number of Satellites90+

Spire Objectives

The constellation of LEMUR satellites operated by Spire Global offer satellite-based maritime, aviation and weather tracking.

Spire Instruments

The LEMUR satellites and their instrumentation are closely bound together as on-board software-defined radio payloads:


STRATOS is an advanced, science-grade Global Navigation Satellite System Earth Observation (GNSS-EO) which makes use of GPS radio occultation measurements from multiple GNSS constellations (GPS, Galileo, GLONASS, and QZSS) to determine temperature, pressure and humidity profiles of Earth's atmosphere for applications in operational meteorology, space weather, and climate. The receiver tracks, on average, five-six dual frequency GPS signals for precision orbit determination (POD) at 1 Hz, as well as multiple simultaneous GNSS satellites at 50 Hz (rising or setting) for the GNSS-RO measurements.


SENSE is a receiver for AIS (Automatic Identification System) signal reception from ships at sea, providing worldwide tracking (identification, position, course and speed information) plus detailed vessel characteristics for maritime safety. The LEMUR satellites have onboard different variants of AIS, are all SDRs capable of receiving AIS messages according to ITU-RM.1371-5 and support operation on all four designated channels, one pair at a time depending on satellite tasking (AIS 1 and AIS 2 channels at 161.975 MHz and 162.025 MHz, or long-range AIS channels at 156.775 MHz and 156.825 MHz)


AIRSAFE uses an ADS-B (Automatic Dependent Surveillance-Broadcast) receiver for tracking of aircraft on a global scale. The directional patch antenna with circular polarisation allow to receive 1090 MHz Mode-S Extended Squitter messages (DF17 and DF18) by using SDR receiver.

Spire Data


The Spire mission is currently under assessment for ESA's Third Party Missions programme. Access to the data is temporarily closed.