Photo: Bill Ingalls · Public domain (US government)
Mission
Government/Top Secret · PO
Tranche 1 Transport Layer B is one of six missions by the United States Space Force Space Development Agency (SDA) for the Proliferated Warfighter Space Architecture (PWSA) Tranche 1 Transport Layer constellation, which will provide assured, resilient, low-latency military data and connectivity…
What it put in orbit
Passes over you For a few days after launch the 21 satellites fly one behind another, a “train” you can see as a line of moving stars. When will it cross your sky?
| Object | Type | Orbit | Globe |
|---|---|---|---|
| PRAETORIAN SDA_602 2025-203A | Payload | 946 × 954 km · 81.3° | Globe |
| PRAETORIAN SDA_603 2025-203B | Payload | 943 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_604 2025-203C | Payload | 950 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_605 2025-203D | Payload | 947 × 958 km · 81.3° | Globe |
| PRAETORIAN SDA_606 2025-203E | Payload | 949 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_607 2025-203F | Payload | 945 × 957 km · 81.3° | Globe |
| PRAETORIAN SDA_608 2025-203G | Payload | 947 × 954 km · 81.3° | Globe |
| PRAETORIAN SDA_609 2025-203H | Payload | 944 × 953 km · 81.3° | Globe |
Show all 21 objects
| PRAETORIAN SDA_610 2025-203J | Payload | 947 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_611 2025-203K | Payload | 949 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_612 2025-203L | Payload | 940 × 952 km · 81.3° | Globe |
| PRAETORIAN SDA_613 2025-203M | Payload | 950 × 958 km · 81.3° | Globe |
| PRAETORIAN SDA_614 2025-203N | Payload | 942 × 952 km · 81.3° | Globe |
| PRAETORIAN SDA_615 2025-203P | Payload | 942 × 954 km · 81.3° | Globe |
| PRAETORIAN SDA_616 2025-203Q | Payload | 949 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_617 2025-203R | Payload | 948 × 958 km · 81.3° | Globe |
| PRAETORIAN SDA_618 2025-203S | Payload | 942 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_619 2025-203T | Payload | 945 × 956 km · 81.3° | Globe |
| PRAETORIAN SDA_620 2025-203U | Payload | 948 × 958 km · 81.3° | Globe |
| PRAETORIAN SDA_621 2025-203V | Payload | 945 × 955 km · 81.3° | Globe |
| PRAETORIAN SDA_601 2025-203W | Payload | 949 × 956 km · 81.3° | Globe |
COSPAR ID 2025-203. Orbits from the CelesTrak satellite catalogue (perigee × apogee, inclination).