# Space Flyer Unit > Japanese research satellite **Wikidata**: [Q3672](https://www.wikidata.org/wiki/Q3672) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Space_Flyer_Unit) **Source**: https://4ort.xyz/entity/space-flyer-unit ## Summary The Space Flyer Unit (SFU) was a Japanese research satellite designed for scientific experimentation in low Earth orbit. Launched in 1995 by an H-II rocket, it was a reusable, 4,000-kilogram spacecraft retrieved by the Space Shuttle Endeavour during mission STS-72 in January 1996. It served as a platform for various experiments before being returned to Earth. ## Key Facts - **Classification:** Research satellite (instance of). - **Launch Date:** March 18, 1995, at 08:01. - **Launch Vehicle:** H-II rocket (specifically the H-II-3F variant). - **Launch Site:** Yoshinobu Launch Complex Launch Pad 1. - **Retrieval Date:** January 13, 1996 (captured by STS-72). - **Landing Date:** January 20, 1996, at 06:41:41. - **Mass:** 4,000 kilograms. - **Dimensions:** 2.8 metres in height, 4.7 metres in diameter, and 24.42 metres in width (spanning its solar arrays). - **Operator:** National Space Development Agency (Japan). - **Manufacturer:** Mitsubishi Electric. - **Identifiers:** COSPAR ID 1995-011A; SCN 23521. ## FAQs ### Q: Was the Space Flyer Unit designed to stay in space permanently? A: No, it was a retrievable spacecraft. It was launched to conduct experiments and was subsequently captured by the Space Shuttle and returned to Earth. ### Q: How was the Space Flyer Unit powered? A: The satellite was powered by two spacecraft solar arrays, which spanned a total width of 24.42 metres. ### Q: Which mission was responsible for retrieving the Space Flyer Unit? A: The STS-72 mission (Space Shuttle Endeavour) captured the satellite on January 13, 1996, using the Canadarm, and landed with it at the Launch and Landing Facility on January 20, 1996. ### Q: Who built and operated the Space Flyer Unit? A: The satellite was manufactured by Mitsubishi Electric and operated by the National Space Development Agency of Japan. ## Why It Matters The Space Flyer Unit represents a significant milestone in spaceflight history as a prime example of reusable spacecraft technology. Unlike most satellites designed for one-way missions or permanent orbital insertion, the SFU was specifically engineered to be recovered, allowing scientists to retrieve experimental data and physical specimens directly from the hardware. This capability bridged the gap between disposable satellite platforms and the Space Shuttle's reusable laboratory functions, enabling long-duration microgravity experiments with the distinct advantage of post-mission physical analysis. Launched by Japan's indigenous H-II rocket, the mission highlighted the nation's growing proficiency in both launch vehicle technology and complex orbital operations. The mission demonstrated a high level of international cooperation and technical precision, requiring a rendezvous between the Japanese satellite and the American Space Shuttle. The successful capture and landing of the SFU provided valuable data that informed future reusable space systems and retrieval protocols, emphasizing the viability of "space trucks" for logistics and research. The spacecraft's substantial mass of 4,000 kg and considerable size also demonstrated the capacity to launch and recover complex, heavy payloads. ## Notable For - **Reusability:** Being a reusable research satellite recovered by the Space Shuttle after nearly 10 months in orbit. - **Launch Vehicle:** Launching aboard the H-II, a Japanese family of rockets, specifically the H-II-3F. - **Retrieval Method:** Its capture via the Canadarm robotic arm during the STS-72 mission. - **Dimensions:** Possessing a large solar array span of 24.42 metres for power generation. - **Cooperation:** Serving as a joint operational success between Japan's National Space Development Agency and NASA's shuttle program. ## Body ### Development and Specifications The Space Flyer Unit (SFU), also known as SFU-1 and associated with the Infrared Telescope in Space project, was a spacecraft manufactured by **Mitsubishi Electric**. It was operated by the **National Space Development Agency** of Japan. Physically, the satellite was substantial, possessing a **mass of 4,000 kilograms**. The main body of the spacecraft had a **diameter of 4.7 metres** and a **height of 2.8 metres**. To power its systems, the SFU utilized two **spacecraft solar arrays** that, when deployed, gave the vehicle a total **width of 24.42 metres**. ### Mission Timeline The SFU was launched on **March 18, 1995**, at 08:01 UTC. It lifted off from the **Yoshinobu Launch Complex Launch Pad 1** aboard an **H-II rocket** (flight configuration H-II-3F). Upon reaching space, it entered a **low Earth orbit** to conduct its research objectives. After roughly ten months in orbit, the satellite became the target of a retrieval operation. On **January 13, 1996**, the crew of **STS-72** (Space Shuttle Endeavour) successfully captured the SFU. The operation utilized the **Canadarm** to grapple the satellite. Following capture, the satellite was stowed in the shuttle's payload bay and returned to Earth. The mission concluded with the landing of STS-72 at the **Launch and Landing Facility** on **January 20, 1996**, at 06:41:41. ### Identifiers and Records The Space Flyer Unit is cataloged in international space databases under the **COSPAR ID 1995-011A** and the **NSSDCA ID 1995-011A**. Its satellite catalog number (SCN) is **23521**. It is also assigned the Wolfram Language entity code `Entity["Satellite", "23521"]`. ## References 1. [Source](https://space.skyrocket.de/doc_sdat/sfu.htm) 2. Jonathan's Space Report 3. [Source](https://www.nasa.gov/mission/sts-72/) 4. Freebase Data Dumps. 2013 5. Lessons learned from the Space Flyer Unit (SFU) mission 6. [Source](https://www.youtube.com/watch?v=VvG6RCr1BYw) 7. [Source](http://www.isas.jaxa.jp/e/enterp/missions/sfu.shtml)