# GSSAP-4

> American near-geosynchronous space surveillance satellite

**Wikidata**: [Q28668994](https://www.wikidata.org/wiki/Q28668994)  
**Source**: https://4ort.xyz/entity/gssap-4

## Summary
GSSAP-4 (Geosynchronous Space Situational Awareness Program-4) is an American military satellite designed for near-geosynchronous space surveillance. Launched in 2016, it is part of a program to monitor objects in geosynchronous orbit for the U.S. military.

## Key Facts
- **Launch Date**: August 19, 2016, at 04:52 UTC from Cape Canaveral Space Launch Complex 37B.
- **Operator**: Combat Forces Command (U.S. military).
- **Manufacturer**: Orbital ATK (now part of Northrop Grumman).
- **Launch Vehicle**: Delta IV Medium+(4,2) rocket.
- **Orbit**: Near-geosynchronous orbit (geosynchronous satellite).
- **Aliases**: Known as Hornet 4 and USA-271.
- **Predecessor**: GSSAP-3; successor is GSSAP-5.
- **Spacecraft Bus**: GEOStar-1 platform.
- **Power Source**: Spacecraft solar array (2 panels).
- **COSPAR ID**: 2016-052B; **NSSDCA ID**: 2016-052B.

## FAQs
### Q: What is the purpose of GSSAP-4?
A: GSSAP-4 is a military satellite used for space surveillance, specifically monitoring objects in near-geosynchronous orbit to enhance situational awareness for the U.S. military.

### Q: When was GSSAP-4 launched?
A: It was launched on August 19, 2016, aboard a Delta IV Medium+(4,2) rocket from Cape Canaveral.

### Q: Who operates GSSAP-4?
A: The satellite is operated by the U.S. Combat Forces Command.

### Q: What is the relationship between GSSAP-4 and other GSSAP satellites?
A: GSSAP-4 is the fourth in a series of near-geosynchronous surveillance satellites, following GSSAP-3 and preceding GSSAP-5.

### Q: What is the spacecraft bus used for GSSAP-4?
A: It uses the GEOStar-1 spacecraft bus, manufactured by Orbital ATK.

## Why It Matters
GSSAP-4 plays a critical role in U.S. space situational awareness by monitoring objects in geosynchronous orbit, a region vital for communications, weather, and national security satellites. Its surveillance capabilities help detect and track potential threats, such as adversarial satellites or debris, ensuring the safety and operational integrity of U.S. and allied space assets. As part of the Geosynchronous Space Situational Awareness Program (GSSAP), it contributes to a broader military effort to maintain dominance in space operations. The satellite’s ability to maneuver near other objects in geosynchronous orbit provides unique insights into space activities, enhancing the U.S. military’s ability to respond to emerging challenges in an increasingly contested domain.

## Notable For
- **First of its kind**: Part of a dedicated program for near-geosynchronous space surveillance.
- **Military significance**: Operated by the U.S. Combat Forces Command for strategic space monitoring.
- **Advanced maneuverability**: Capable of operating near other geosynchronous objects for close inspection.
- **Part of a constellation**: Works alongside other GSSAP satellites (e.g., GSSAP-3 and GSSAP-5) for comprehensive coverage.
- **High-profile launch**: Deployed using the Delta IV Medium+(4,2) rocket, a reliable U.S. launch vehicle.

## Body
### Overview
GSSAP-4 is an American military satellite designed for space surveillance in near-geosynchronous orbit. It is part of the Geosynchronous Space Situational Awareness Program (GSSAP), which aims to monitor and track objects in this critical orbital regime.

### Launch and Deployment
- **Launch Date**: August 19, 2016, at 04:52 UTC.
- **Launch Site**: Cape Canaveral Space Launch Complex 37B.
- **Launch Vehicle**: Delta IV Medium+(4,2) (variant D-375/D4-33).
- **Orbit**: Near-geosynchronous, allowing it to monitor objects in geosynchronous orbit.

### Technical Specifications
- **Spacecraft Bus**: GEOStar-1, manufactured by Orbital ATK.
- **Power Source**: Spacecraft solar array with two panels.
- **Operator**: U.S. Combat Forces Command.
- **Aliases**: Hornet 4, USA-271.
- **Identifiers**:
  - COSPAR ID: 2016-052B
  - NSSDCA ID: 2016-052B
  - Satellite Catalog Number (SCN): 41745

### Program Context
GSSAP-4 is the fourth satellite in the GSSAP series, following GSSAP-3 and preceding GSSAP-5. The program is designed to provide the U.S. military with enhanced space situational awareness, particularly in the geosynchronous orbit region, which is heavily used for communications, weather monitoring, and national security satellites.

### Operational Milestones
- **Service Entry**: Achieved initial operating capability on September 12, 2017.
- **Surveillance Role**: Monitors other satellites and debris in geosynchronous orbit, supporting U.S. space defense efforts.

## Schema Markup
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  "@type": "Thing",
  "name": "GSSAP-4",
  "description": "American near-geosynchronous space surveillance satellite",
  "sameAs": [
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    "https://en.wikipedia.org/wiki/Geosynchronous_Space_Situational_Awareness_Program"
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## References

1. [Source](https://space.skyrocket.de/doc_sdat/gssap-1.htm)
2. [Source](https://www.airforcemag.com/weapons-platforms/gssap/)
3. Jonathan's Space Report