# Cluster > intended constellation of four European Space Agency spacecraft; destroyed during launch failure **Wikidata**: [Q367351](https://www.wikidata.org/wiki/Q367351) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Cluster_(spacecraft)) **Source**: https://4ort.xyz/entity/cluster ## Summary Cluster was an intended constellation of four European Space Agency (ESA) spacecraft designed to study Earth's magnetosphere. The mission failed during launch on June 4, 1996, when the Ariane 5G rocket carrying the satellites exploded shortly after liftoff. ## Key Facts - **Launch date**: June 4, 1996, at 12:34:06 UTC - **Launch vehicle**: Ariane 5G (flight V88) - **Operator**: European Space Agency (ESA) - **Manufacturer**: Dornier - **Space tug**: EPS L9.7 - **Subclass**: Geomagnetic satellite (designed to monitor Earth's magnetosphere) - **Replaced by**: Cluster II (successful follow-up mission) - **Significant event**: Launch failure due to rocket malfunction - **Wikipedia title**: Cluster (spacecraft) - **Aliases**: Mision Cluster ## FAQs ### Q: What was the purpose of the Cluster mission? A: The Cluster mission aimed to study Earth's magnetosphere and related regions using a constellation of four spacecraft. The satellites were designed to provide detailed observations of space weather phenomena. ### Q: Why did the Cluster mission fail? A: The mission failed during launch when the Ariane 5G rocket carrying the satellites exploded shortly after liftoff on June 4, 1996. The cause was a malfunction in the rocket's inertial reference system. ### Q: What was the relationship between Cluster and Cluster II? A: Cluster II was the successor mission to Cluster. After the failure of the original Cluster mission, ESA launched Cluster II in 2000, which successfully deployed four satellites to study Earth's magnetosphere. ### Q: Who operated the Cluster mission? A: The Cluster mission was operated by the European Space Agency (ESA), with support from Dornier as the manufacturer of the spacecraft. ### Q: What was the significance of the Cluster mission's failure? A: The failure of the Cluster mission highlighted the risks of space exploration and the complexity of launching multiple satellites simultaneously. It led to the development of Cluster II, which successfully achieved its scientific objectives. ## Why It Matters The Cluster mission was a significant endeavor in space science, aiming to provide unprecedented insights into Earth's magnetosphere and its interaction with the solar wind. The failure of the original mission was a setback but also a learning opportunity for ESA and the global space community. The subsequent success of Cluster II demonstrated the resilience and adaptability of space agencies in overcoming challenges. The mission's data, though limited, contributed to our understanding of space weather and its effects on Earth's environment. The failure also underscored the importance of rigorous testing and redundancy in space missions, ensuring the safety and success of future endeavors. ## Notable For - **First of its kind**: Cluster was one of the first missions to use a constellation of spacecraft to study Earth's magnetosphere. - **Technological innovation**: The mission employed advanced instrumentation and data processing techniques for its time. - **Scientific impact**: Despite the failure, Cluster II's success provided valuable data on space weather and magnetospheric dynamics. - **International collaboration**: The mission involved contributions from multiple European countries and international partners. - **Legacy**: The failure of Cluster served as a catalyst for improvements in launch vehicle safety and mission design. ## Body ### Mission Overview Cluster was a planned constellation of four identical spacecraft developed by the European Space Agency (ESA) to study Earth's magnetosphere. The mission aimed to investigate the interaction between the solar wind and Earth's magnetic field, as well as the dynamics of the magnetosphere. The satellites were designed to fly in formation, providing three-dimensional measurements of plasma and magnetic fields. ### Launch and Failure The Cluster mission launched on June 4, 1996, aboard an Ariane 5G rocket (flight V88) from the Guiana Space Centre in French Guiana. The launch was intended to place the four satellites into polar orbits. However, approximately 37 seconds after liftoff, the rocket experienced a catastrophic failure due to a malfunction in its inertial reference system. The resulting explosion destroyed all four satellites and the Ariane 5G rocket. ### Subsequent Mission: Cluster II Following the failure of the original Cluster mission, ESA developed Cluster II, which successfully launched on August 16, 2000. Cluster II consisted of four identical satellites equipped with advanced instrumentation to study Earth's magnetosphere. The mission achieved its scientific objectives, providing valuable data on space weather and magnetospheric dynamics. ### Scientific Instruments and Objectives The Cluster satellites were equipped with a suite of scientific instruments, including: - **Fluxgate Magnetometer**: To measure magnetic field variations. - **Electron Drift Instrument**: To study plasma dynamics. - **Ion Spectrometer**: To analyze ion composition and energy. - **Electric Field and Wave Instruments**: To detect electric field fluctuations and plasma waves. ### Legacy and Impact The failure of the original Cluster mission was a significant setback for ESA, but it also led to improvements in launch vehicle safety and mission design. Cluster II's success demonstrated the resilience of the space community and the importance of redundancy in space missions. The data collected by Cluster II has contributed to our understanding of space weather and its effects on Earth's environment, making it a notable achievement in space science. ## References 1. [Source](https://space.skyrocket.de/doc_sdat/cluster.htm) 2. Jonathan's Space Report 3. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)