Overview
The International Space Station is a modular space station in low Earth orbit, jointly operated by NASA (United States), Roscosmos (Russia), ESA (Europe), JAXA (Japan), and CSA (Canada). It has been continuously occupied since November 2000 — the longest uninterrupted human presence in space. The ISS serves primarily as a microgravity research laboratory, conducting over 4,000 experiments across biology, physics, medicine, and materials science. See our complete ISS modules guide for a breakdown of every component.
Key Facts
| NORAD ID | 25544 |
| COSPAR ID | 1998-067A |
| First Element Launch | 20 November 1998 (Zarya module) |
| Continuously Crewed Since | 2 November 2000 |
| Orbit | ~420 km altitude, 51.6° inclination, ~92 min period |
| Speed | ~27,600 km/h (7.66 km/s) |
| Dimensions | 109 m × 73 m (truss span × module length) |
| Pressurised Volume | ~916 m³ |
| Solar Array Span | 73 m, generating ~120 kW |
| Crew Size | Typically 6–7 (up to 13 during handovers) |
| Visitors | 270+ people from 20+ countries |
| Assembly Flights | 42 assembly missions |
| Planned Retirement | 2030 (US Senate considering extension to 2032) |
Visibility
The ISS is the brightest satellite in the sky, reaching magnitude –3.5 on good passes — brighter than any star. Its massive solar arrays reflect sunlight brilliantly. It is visible as a steady, bright, fast-moving point of light crossing the sky in 3–6 minutes. See our ISS visibility guide for pass predictions.
Future
NASA has extended ISS operations through 2030, with the US Senate considering legislation to push retirement to 2032. After retirement, the station will undergo controlled deorbiting using a SpaceX-built US Deorbit Vehicle, targeting the South Pacific Uninhabited Area (Point Nemo). Commercial space stations from Axiom Space, Blue Origin, and others are expected to serve as successors.