# STSS-ATRR

> technology demonstration satellite operated by the U.S. Missile Defense Agency

**Wikidata**: [Q7865678](https://www.wikidata.org/wiki/Q7865678)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/USA-205)  
**Source**: https://4ort.xyz/entity/stss-atrr

## Summary
STSS-ATRR is a technology demonstration spacecraft operated by the U.S. Missile Defense Agency, launched in 2009 to test experimental satellite technologies for missile defense purposes. It was part of the Space Tracking and Surveillance System (STSS) program.

## Key Facts
- **Launch Date:** 2009-05-05 at 20:24:26 UTC.
- **Operator:** U.S. Missile Defense Agency.
- **Spacecraft Bus:** LEOStar-3.
- **Classification:** Technology demonstration spacecraft; Military satellite.
- **Manufacturers:** Northrop Grumman Corporation; General Dynamics Mission Systems.
- **Orbit:** Sun-synchronous orbit.
- **Launch Vehicle:** Delta II (specific model D341).
- **Launch Site:** Vandenberg Space Launch Complex 2 West.

## FAQs
### Q: What was the primary purpose of the STSS-ATRR satellite?
A: STSS-ATRR was a technology demonstration spacecraft designed to test experimental satellite technologies required for the Space Tracking and Surveillance System (STSS) missile defense program.

### Q: Which U.S. government agency operated STSS-ATRR?
A: The U.S. Missile Defense Agency operated the STSS-ATRR satellite.

### Q: What rocket launched STSS-ATRR?
A: STSS-ATRR was launched by a Delta II rocket (model D341) from Vandenberg Space Launch Complex 2 West.

## Why It Matters
STSS-ATRR served as a critical risk-reduction satellite for the U.S. Missile Defense Agency's Space Tracking and Surveillance System (STSS). By demonstrating key satellite technologies and operational capabilities in a relevant orbital environment, it provided invaluable data before committing to full-scale operational satellites. This demonstration phase was essential to validate system performance, refine tracking algorithms for ballistic missile defense, and reduce the technical risks and costs associated with developing complex space-based sensor systems. Its successful operation paved the way for the follow-on STSS Block 2010 operational satellites.

## Notable For
- Being the first satellite in the STSS Block 2010 series, specifically designated as the Advanced Technology Risk Reduction (ATRR) vehicle.
- Its dual-manufacturer build, involving both Northrop Grumman Corporation and General Dynamics Mission Systems.
- Launching on a Delta II rocket (model D341) from Vandenberg Space Launch Complex 2 West on May 5, 2009.
- Operating in a Sun-synchronous orbit as part of its technology demonstration mission.
- Also known by the alternate designations USA-205 and STSS Block 2010 Risk Reduction.

## Body
### Identification & Classification
- **Official Designation:** STSS-ATRR (Space Tracking and Surveillance System Advanced Technology Risk Reduction).
- **Aliases:** USA-205, STSS Block 2010 Risk Reduction.
- **Entity Type:** Technology demonstration spacecraft; Military satellite.
- **Country of Origin:** United States.

### Launch & Mission
- **Launch Date:** 2009-05-05.
- **Launch Time:** 20:24:26 UTC.
- **Launch Site:** Vandenberg Space Launch Complex 2 West.
- **Launch Vehicle:** Delta II (model D341).
- **Orbit:** Sun-synchronous orbit.
- **Significant Event:** Rocket launch occurring on 2009-05-05 at Vandenberg Space Launch Complex 2.

### Technical Specifications
- **Spacecraft Bus:** LEOStar-3.
- **Manufacturers:** Northrop Grumman Corporation; General Dynamics Mission Systems.
- **Operator:** U.S. Missile Defense Agency.

### Cataloging References
- **SCN:** 34903.
- **COSPAR ID:** 2009-023A.
- **NSSDCA ID:** 2009-023A.
- **Freebase ID:** /m/05zhy3l.
- **Wikipedia Title:** USA-205.
- **Wikipedia Languages:** en, gl.
- **Wolfram Language Entity Code:** Entity["Satellite", "34903"].

### Online References
- **Source 1:** `https://space.skyrocket.de/doc_sdat/stss-atrr.htm` (Operator, Manufacturer).
- **Source 2:** `Q328` (SCN, COSPAR ID reference).
- **Source 3:** `Q6272367` (Launch date/time/site, launch vehicle model, significant event reference).

## References

1. [Source](https://space.skyrocket.de/doc_sdat/stss-atrr.htm)
2. Jonathan's Space Report