# STPSat-4

> U.S. Air Force technology demonstration satellite

**Wikidata**: [Q114814326](https://www.wikidata.org/wiki/Q114814326)  
**Source**: https://4ort.xyz/entity/stpsat-4

## Summary
STPSat-4 is a U.S. Air Force technology demonstration satellite operated by the Space Test Program to flight-test experimental space technologies. It was launched on 2019-11-02 on an Antares rocket as part of the Cygnus NG-12 mission, later deployed from the International Space Station in January 2020, and re‑entered the atmosphere on 2022-10-04.

## Key Facts
- Official name: STPSat-4; instance of a technology demonstration spacecraft.  
- Country of origin: United States.  
- Operator: Space Test Program.  
- Manufacturer: MEI Technologies.  
- Launch date and time: 2019-11-02 at 13:59:47 (UTC).  
- Launch vehicle and mission: Antares (variant 2TRS2S1.11) as part of the Cygnus NG-12 mission.  
- Launch site: Mid-Atlantic Regional Spaceport, Launch Pad 0A.  
- Deployment: Deployed from the International Space Station in January 2020.  
- Orbit: Low Earth orbit (satellite_of: low Earth orbit).  
- Decay (atmospheric entry): 2022-10-04.  
- Identifiers: SCN 45043; COSPAR ID 1998-067QY; NSSDCA ID 1998067QY.  
- NASA ISS experiment ID: 7347.  
- Program relationships: Follows STPSat-5 and is followed by STPSat-6.

## FAQs
### Q: What is STPSat-4?
A: STPSat-4 is a U.S. Air Force technology demonstration satellite operated by the Space Test Program to demonstrate experimental technologies in low Earth orbit.

### Q: When and how was STPSat-4 launched?
A: STPSat-4 was launched on 2019-11-02 at 13:59:47 UTC aboard an Antares rocket (variant 2TRS2S1.11) from Mid-Atlantic Regional Spaceport Launch Pad 0A as part of the Cygnus NG-12 mission.

### Q: How and when was STPSat-4 deployed into orbit?
A: After launch, STPSat-4 was carried to the International Space Station on the Cygnus NG-12 resupply mission and was deployed from the ISS in January 2020.

### Q: When did STPSat-4 re-enter the atmosphere?
A: STPSat-4 experienced atmospheric entry (orbit decay) on 2022-10-04.

### Q: Who built and operated STPSat-4?
A: STPSat-4 was manufactured by MEI Technologies and operated by the Space Test Program of the United States.

## Why It Matters
STPSat-4 is part of the U.S. military’s Space Test Program, which fields small spacecraft specifically to demonstrate and validate experimental technologies in space. As a technology demonstration satellite, STPSat-4 enabled the Space Test Program and its stakeholders to test hardware, software, or operational concepts in a relevant low Earth orbit environment without committing to a full operational satellite. Its launch via a commercial Antares/Cygnus resupply flight illustrates the use of commercial launch and ISS deployment pathways to place experimental payloads into orbit. The satellite’s lifecycle—from launch on 2019-11-02, ISS deployment in January 2020, to atmospheric entry on 2022-10-04—provides a concrete example of how short-duration, risk-tolerant flight-test missions are executed to mature technologies for future military and civil space systems. STPSat-4’s identifiers and program relationships (SCN 45043, COSPAR 1998-067QY, follows STPSat-5, followed by STPSat-6) place it in the continuum of Space Test Program efforts to accelerate space technology readiness.

## Notable For
- Launch and delivery method: Launched on Antares and carried to the ISS on the Cygnus NG-12 mission before being deployed from the station.  
- Program role: Served explicitly as a technology demonstration satellite under the U.S. Space Test Program.  
- Manufacturer: Built by MEI Technologies for the Space Test Program.  
- Clear lifecycle: Launched 2019-11-02, ISS deployment January 2020, and atmospheric entry 2022-10-04.  
- Official identifiers: COSPAR 1998-067QY and SCN 45043, enabling tracking and archival reference.

## Body

### Overview
- Official name: STPSat-4.  
- Type: Technology demonstration spacecraft.  
- Role: To demonstrate experimental technologies in low Earth orbit for the Space Test Program.

### Launch and Delivery
- Launch date and time: 2019-11-02 at 13:59:47 (UTC).  
- Launch vehicle: Antares, variant 2TRS2S1.11.  
- Launch site: Mid-Atlantic Regional Spaceport (MARS), Launch Pad 0A.  
- Mission context: Launched as part of the Cygnus NG-12 mission.  
- Delivery pathway: Transported to the International Space Station on Cygnus NG-12 and subsequently deployed from the ISS in January 2020.

### Orbital details and decay
- Orbit regime: Low Earth orbit.  
- COSPAR ID: 1998-067QY.  
- NSSDCA ID: 1998067QY.  
- SCN (Satellite Catalog Number): 45043.  
- Time of orbit decay / atmospheric entry: 2022-10-04.

### Operator, manufacturer, and program relationships
- Operator: Space Test Program.  
- Manufacturer: MEI Technologies.  
- Country of origin: United States.  
- Program lineage: Listed as following STPSat-5 and preceding STPSat-6 within the program sequence.  
- NASA ISS experiment ID: 7347.

### Significant events (selected)
- Rocket launch: 2019-11-02 from MARS Launch Pad 0A as part of Cygnus NG-12.  
- Deployment: Deployed from the International Space Station in January 2020.  
- Atmospheric entry: 2022-10-04.

## Schema Markup
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  "name": "STPSat-4",
  "description": "STPSat-4 is a U.S. Air Force technology demonstration satellite operated by the Space Test Program to demonstrate experimental technologies in low Earth orbit.",
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## References

1. [Source](https://space.skyrocket.de/doc_sdat/stpsat-4.htm)
2. Jonathan's Space Report
3. [Source](https://www.n2yo.com/satellite/?s=45043)