Humanity's outpost in low Earth orbit. Continuously inhabited since November 2000, the ISS is the largest structure ever built in space.
EVA spacewalk simulation. Drag to orbit, scroll to zoom. ISS model with animated astronaut.
Orbital altitude
408 km
Low Earth Orbit
Speed
27,600 km/h
7.66 km/s
Orbital period
92 minutes
~15.5 orbits per day
Mass
420,000 kg
Largest structure in orbit
Length
109 m
About the size of a football field
Width (truss)
73 m
Solar array span
Pressurized volume
916 m³
Roughly a Boeing 747
Crew capacity
6-7
Continuous occupation since 2000
The ISS was assembled piece by piece over 13 years, with components launched by the Space Shuttle, Proton, and Soyuz rockets.
The first module launched. Provided initial power, propulsion, and guidance during early assembly.
First US-built node, connecting Russian and American segments. Has six docking ports.
Service module providing life support, living quarters, and station control for the Russian segment.
Primary research laboratory for US payloads. Houses 24 equipment racks for experiments.
European research laboratory. Supports experiments in fluid physics, materials science, and life sciences.
Largest single module. Includes a pressurized lab, logistics module, exposed experiment platform, and robotic arm.
Seven-window observation dome providing a 360-degree view of Earth and space. Used for robotic arm operations.
Houses life support systems including water recycling, oxygen generation, and carbon dioxide removal.
Astronauts follow a structured schedule coordinated with mission control. Here's a typical day on the ISS.
Astronauts sleep in private crew quarters in sleeping bags attached to the wall.
Personal hygiene (no showers - wet wipes only) and rehydrated or thermostabilized meals.
Video call with mission control centers in Houston, Moscow, and partner agencies.
5-6 hours of research: microgravity experiments, medical studies, technology demos.
Crew gathers to eat together when possible. Food includes tortillas (crumbs are dangerous in microgravity).
Station maintenance, repairs, software updates, and continuing research.
Treadmill, stationary bike, and resistive exercise device. Without exercise, astronauts lose 1-2% bone mass per month.
Evening meal, personal calls to family, photography, reading, or watching Earth from the Cupola.
Crew quarters block light and noise. The ISS experiences 16 sunrises and sunsets per day.
Without gravity masking subtle forces, scientists can study fluid dynamics, combustion, crystal growth, and material properties impossible to observe on Earth. Results have improved manufacturing processes and medications.
Astronauts' bodies are studied extensively: bone density loss, muscle atrophy, vision changes, immune system changes, and psychological effects of isolation. This data is essential for planning Mars missions.
The ISS orbits at the perfect altitude for monitoring climate change, natural disasters, urban growth, and agricultural patterns. Astronauts have taken over 4 million photographs of Earth.
The ISS tests new technologies in the space environment: life support systems, water recycling, radiation shielding, robotic systems, and communication technologies for future deep-space missions.
Zarya module launched (Nov 20), followed by Unity (Dec 4). Assembly begins.
Expedition 1 arrives (Nov 2). Continuous human occupation begins.
Destiny laboratory installed. Canadarm2 robotic arm attached.
Columbus (ESA) and Kibo (JAXA) laboratories added. Station at major milestone.
Cupola observation dome and Tranquility node installed.
Space Shuttle program ends. Station construction essentially complete.
SpaceX Crew Dragon begins regular crew flights. Commercial crew era starts.
25 years of continuous human occupation. Over 270 people from 21 countries have visited.
Planned deorbit. Will be deliberately brought down over the Pacific Ocean.
The ISS is the third brightest object in the night sky after the Sun and Moon. It appears as a bright, fast-moving point of light that doesn't blink (unlike airplanes).
Look during dawn or dusk when the sky is dark but the ISS is still sunlit. It crosses the sky in 3-5 minutes, travelling from west to east.
Visit spotthestation.nasa.gov to sign up for alerts when the ISS will pass over your location.
| Metric | ISS | Orion |
|---|---|---|
| Altitude | 408 km (LEO) | Up to 413,146 km |
| Speed | 27,600 km/h | Up to 38,400 km/h |
| Crew | 6-7 (long duration) | 4 (10-day mission) |
| Volume | 916 m³ | 19.6 m³ |
| Mass | 420,000 kg | 27,000 kg |
| Purpose | Research laboratory | Deep space exploration |
| Destination | Low Earth Orbit | The Moon and beyond |
| Duration | Continuous (since 2000) | 10-day missions |