# Landsat 9

> American Earth observation satellite

**Wikidata**: [Q19838561](https://www.wikidata.org/wiki/Q19838561)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Landsat_9)  
**Source**: https://4ort.xyz/entity/landsat-9

## Summary  
Landsat 9 is an American Earth observation satellite launched on September 27, 2021, to monitor land use and environmental changes across the globe. It continues the legacy of the long-running Landsat program, providing critical data for agriculture, climate monitoring, and natural resource management. The satellite operates in a Sun-synchronous orbit and carries advanced imaging instruments to capture high-resolution images of Earth’s surface.

## Key Facts  
- Launched on September 27, 2021, at 18:12 UTC from Vandenberg Space Launch Complex 3 East  
- Operated by NASA and the United States Geological Survey (USGS)  
- Mass at launch: 2,864 kilograms (launch weight)  
- Part of the Landsat program, succeeding Landsat 8  
- Carries two main scientific instruments: Operational Land Imager 2 (OLI-2) and Thermal Infrared Sensor 2 (TIRS-2)  
- Built using the LEOStar-3 spacecraft bus  
- Orbit inclination: 98.2 degrees  
- Country of origin: United States  
- Manufacturer: Northrop Grumman Innovation Systems (prime contractor)  

## FAQs  
### Q: What is Landsat 9 used for?  
A: Landsat 9 monitors Earth's land surfaces to track changes in vegetation, urban growth, water resources, and natural disasters. Its data supports scientific research, policy-making, and sustainable land management practices globally.

### Q: When was Landsat 9 launched?  
A: Landsat 9 was launched on September 27, 2021, at 18:12 UTC from Vandenberg Space Launch Complex 3 East in California.

### Q: Who operates Landsat 9?  
A: Landsat 9 is jointly operated by NASA and the United States Geological Survey (USGS), with USGS taking the lead in mission operations and data distribution.

## Why It Matters  
Landsat 9 plays a crucial role in maintaining a continuous record of Earth’s land surface changes dating back to 1972, making it invaluable for understanding long-term environmental trends. Its imagery supports global efforts in food security, disaster response, ecosystem monitoring, and climate science. By ensuring continuity with previous Landsat missions, particularly Landsat 8, it enables consistent time-series analysis essential for detecting gradual shifts like deforestation or urban sprawl. The satellite also contributes to international cooperation in Earth sciences, offering free and open access to its data for researchers, governments, and organizations worldwide.

## Notable For  
- Continuation of the longest-running Earth observation program (since 1972)  
- Dual-instrument payload (OLI-2 and TIRS-2) enabling multispectral and thermal infrared imaging  
- Free and publicly accessible data through USGS platforms  
- Joint operation between NASA and USGS, combining technical expertise and operational efficiency  

## Body  
### Mission Overview  
Landsat 9 is the latest satellite in the Landsat program, which has been continuously observing Earth since 1972. Designed to work in tandem with Landsat 8, it ensures uninterrupted global coverage and extends the historical dataset vital for environmental and climate studies.

### Launch Details  
- **Launch Date**: September 27, 2021  
- **Launch Time**: 18:12 UTC  
- **Launch Site**: Vandenberg Space Launch Complex 3 East  
- **Launch Vehicle**: Atlas V 401 (AV-092)  

### Technical Specifications  
- **Mass**: 2,864 kg (launch weight)  
- **Spacecraft Bus**: LEOStar-3  
- **Orbit Type**: Sun-synchronous orbit  
- **Orbital Inclination**: 98.2°  
- **Mission Sponsor**: NASA  
- **Operator**: United States Geological Survey (USGS)  

### Instruments  
Landsat 9 carries two primary instruments:  
- **Operational Land Imager 2 (OLI-2)** – Developed by Ball Aerospace & Technologies, captures visible, near-infrared, and shortwave infrared light  
- **Thermal Infrared Sensor 2 (TIRS-2)** – Developed by NASA's Goddard Space Flight Center, measures thermal emissions for temperature-related studies  

### Manufacturers and Contractors  
- **Prime Contractor**: Northrop Grumman Innovation Systems  
- **Subcontractors**:
  - Ball Aerospace & Technologies (for OLI-2)
  - Goddard Space Flight Center (for TIRS-2)

### Program Context  
- **Part Of**: Landsat Program  
- **Predecessor**: Landsat 8  
- **Continuity Goal**: Maintain overlap with Landsat 8 for calibration and seamless data transition  

### Data Access and Impact  
Data collected by Landsat 9 is freely available via USGS systems such as EarthExplorer. This accessibility allows scientists, educators, and policymakers around the world to analyze land cover changes over decades, supporting informed decision-making in areas ranging from agriculture to conservation.

## Schema Markup  
```json
{
  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "Landsat 9",
  "description": "American Earth observation satellite launched in 2021 to continue the Landsat program.",
  "url": "https://landsat.gsfc.nasa.gov/satellites/landsat-9/",
  "sameAs": [
    "https://www.wikidata.org/wiki/Q49260",
    "https://en.wikipedia.org/wiki/Landsat_9"
  ],
  "additionalType": "Earth observation satellite"
}

## References

1. [Source](https://spacenews.com/atlas-5-launches-landsat-9/)
2. [Source](https://www.nasaspaceflight.com/2021/09/nasa-landsat-9-launch/)
3. [Source](https://landsat.gsfc.nasa.gov/landsat-9/landsat-9-overview)
4. Jonathan's Space Report
5. [Source](https://twitter.com/ulalaunch/status/1442582998407340042)
6. [Source](https://space.skyrocket.de/doc_sdat/landsat-8.htm)
7. [Source](https://spaceflightnow.com/2021/09/27/new-eye-on-planet-earth-rockets-into-orbit-from-california/)