International space station orbit altitude
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International Space Station Orbit Altitude Overview
The International Space Station (ISS) orbits Earth at an altitude of approximately 400 kilometers (km) above the surface. This altitude places the ISS in low Earth orbit (LEO), which is ideal for both scientific research and operational efficiency. The station’s orbital inclination is 51.6 degrees, allowing it to pass over a large portion of the Earth's surface, including most populated and scientifically interesting regions 128910.
Variations and Operational Range of ISS Altitude
While the nominal altitude is about 400 km, the ISS’s orbit can vary slightly due to atmospheric drag and operational needs. Some sources note that the ISS has also operated at altitudes as low as 370 km, especially during certain mission phases or reboost maneuvers . The upper bound for the ISS’s operational altitude is generally set by the balance between atmospheric drag (which increases at lower altitudes) and the capabilities of visiting spacecraft to deliver supplies and perform reboosts 367.
Impact of Altitude on ISS Operations
Atmospheric Drag and Reboosts
At around 400 km, the ISS experiences enough atmospheric drag that its orbit gradually decays, requiring periodic reboosts to maintain altitude. These reboosts are carefully planned to optimize fuel use and minimize the frequency of maneuvers, as well as to ensure the station remains within a safe and operational altitude range 67.
Environmental and Research Benefits
The 400 km altitude provides a unique vantage point for Earth and space science. It allows the ISS to observe atmospheric phenomena, such as thunderstorms, with high resolution and at all local times, which is valuable for climate and weather research 25. The microgravity environment at this altitude is also essential for a wide range of biological and physical science experiments 15.
Radiation and Electrostatic Environment
At this altitude, the ISS is exposed to higher levels of cosmic radiation and charged particles compared to the Earth's surface, but it is still partially shielded by the planet’s magnetic field and atmosphere. This environment is carefully monitored to protect both crew and equipment 8910.
Conclusion
The International Space Station orbits at an altitude of about 400 km, with slight variations due to operational needs and atmospheric drag. This altitude is optimal for scientific research, Earth observation, and maintaining a safe and sustainable environment for long-term human habitation in space. The ISS’s position in low Earth orbit continues to provide unique opportunities for research and technology development that benefit both space exploration and life on Earth 12456789+1 MORE.
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