# CRISTA-SPAS II

> free-flying observatory carried on Space Shuttle mission STS-85

**Wikidata**: [Q111498604](https://www.wikidata.org/wiki/Q111498604)  
**Source**: https://4ort.xyz/entity/crista-spas-ii

## Summary
CRISTA-SPAS II was a free-flying observatory carried on NASA's Space Shuttle mission STS-85 in 1997. It was a space telescope designed to study Earth's atmosphere, particularly its infrared emissions, and followed the CRISTA-SPAS I mission.

## Key Facts
- **Class**: Space telescope and payload
- **Mass**: 3,260 kilograms
- **Launch Date**: August 7, 1997, at 14:41 UTC
- **Launch Vehicle**: Space Shuttle *Discovery* (STS-85 mission)
- **Operators**: German Space Agency (DLR) and NASA
- **Manufacturer**: DASA (German Aerospace Center)
- **Spacecraft Bus**: Shuttle Pallet Satellite
- **Country of Origin**: Germany
- **Scientific Instrument**: Carried the CRISTA (Cryogenic Infrared Spectrometers & Telescopes for the Atmosphere) instrument
- **Predecessor**: CRISTA-SPAS I (launched on STS-66 in 1994)

## FAQs
### Q: What was CRISTA-SPAS II used for?
A: CRISTA-SPAS II was a space telescope designed to study Earth's atmospheric infrared emissions, particularly ozone and other trace gases, by measuring their spectral signatures.

### Q: Who operated CRISTA-SPAS II?
A: The observatory was operated jointly by the German Space Agency (DLR) and NASA, with DASA as the manufacturer.

### Q: How did CRISTA-SPAS II differ from its predecessor?
A: CRISTA-SPAS II was the second mission in the series, following CRISTA-SPAS I (launched on STS-66 in 1994), and carried improved instrumentation for atmospheric research.

### Q: What was the launch vehicle for CRISTA-SPAS II?
A: It was launched aboard the Space Shuttle *Discovery* during mission STS-85 in August 1997.

### Q: What was the significance of the CRISTA instrument?
A: The CRISTA instrument was designed to measure infrared emissions from Earth's atmosphere, providing data on ozone and other trace gases to study atmospheric chemistry.

## Why It Matters
CRISTA-SPAS II played a crucial role in atmospheric research by providing high-resolution infrared measurements of Earth's atmosphere. Its data contributed to understanding ozone dynamics, trace gas distribution, and climate processes. As a free-flying observatory deployed from the Space Shuttle, it demonstrated the feasibility of conducting specialized space science missions beyond traditional satellite operations. The mission also highlighted international collaboration between NASA and the German Space Agency (DLR), combining their expertise in atmospheric science and space technology. Its findings helped refine models of atmospheric chemistry and supported environmental monitoring efforts.

## Notable For
- **Atmospheric Research**: Provided critical data on Earth's ozone and trace gas distribution.
- **International Collaboration**: Joint mission between NASA and the German Space Agency (DLR).
- **Innovative Deployment**: Launched as a free-flying payload from the Space Shuttle, expanding mission capabilities.
- **Precursor to Later Missions**: Influenced subsequent atmospheric science missions.
- **High-Resolution Measurements**: Used advanced infrared spectroscopy to study atmospheric composition.

## Body
### Mission Overview
CRISTA-SPAS II was a free-flying observatory launched on August 7, 1997, aboard the Space Shuttle *Discovery* during mission STS-85. It was part of the CRISTA-SPAS series, following CRISTA-SPAS I (launched on STS-66 in 1994). The mission focused on studying Earth's atmosphere using infrared spectroscopy.

### Scientific Instruments
The primary instrument was CRISTA, which measured infrared emissions from the atmosphere to analyze ozone and trace gases. The observatory was mounted on a Shuttle Pallet Satellite (SPAS) platform, allowing it to operate independently from the Shuttle.

### Launch and Operations
- **Launch Date**: August 7, 1997, at 14:41 UTC
- **Launch Site**: Kennedy Space Center Launch Complex 39A
- **Launch Vehicle**: Space Shuttle *Discovery* (STS-85)
- **Mass**: 3,260 kilograms

### Significance
CRISTA-SPAS II provided high-resolution data on atmospheric composition, contributing to climate research and environmental monitoring. Its joint operation by NASA and the German Space Agency (DLR) demonstrated international cooperation in space science.

### Legacy
The mission laid the groundwork for future atmospheric research and showcased the versatility of the Space Shuttle as a platform for specialized scientific payloads. Its data remains valuable for studying atmospheric chemistry and climate processes.

## References

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