Have you ever wondered how the International Space Station (ISS) orbits the Earth without burning up?

At a staggering weight equivalent to 77 elephants, this massive space laboratory is a hub for scientists and researchers from across the globe, contributing breakthroughs in fields like medicine, microbiology, and Earth and space sciences!

Zooming around our planet at an incredible speed of 5 miles per second (8 kilometers per second)—that’s fast enough to travel from Atlanta to London in just 14 minutes—you're probably left wondering: how does it avoid the fiery fate of meteoroids that burn up upon entering Earth’s atmosphere?

Why Do Meteoroids Burn Up Anyway?

Meteoroids, those small chunks of rock and metal, speed through space at shocking velocities between 7 and 25 miles per second (12 to 40 km per second). When their paths cross with Earth, they plunge into our atmosphere, where they face a hostile environment.

As meteoroids enter the mesosphere—30 to 50 miles (48 to 80 kilometers) above the Earth—they crash into particles in the atmosphere. Even though there’s less air at high altitudes, the meteoroids still collide with these particles, generating immense heat and pressure, causing them to disintegrate in a dazzling display often mistaken for shooting stars.

So, What Makes the ISS Different?

The ISS orbits at a much higher altitude, approximately 250 miles (402 kilometers) above the Earth’s surface, well within the thermosphere. This layer of the atmosphere is incredibly thin—so much so that to accumulate a mass equivalent to just one apple, you’d need a container the size of Lake Superior! Because of this sparse particle density, the ISS avoids the intense heat and pressures that meteoroids encounter.

Despite not burning up, the ISS is not without its challenges. As it orbits, temperature swings are extreme. When exposed to sunlight, temperatures can soar to approximately 250°F (121°C) but can plunge down to a chilling -250°F (-156°C) in the dark, creating a staggering difference of 500°F (277°C). To combat these conditions, engineers meticulously chose materials capable of withstanding such fluctuations, keeping the interior at comfortable living conditions for astronauts.

The ISS: A Gateway to Scientific Understanding

From its high-altitude vantage point, the ISS has greatly enhanced our knowledge of vital topics like Earth’s water and energy cycles, food cultivation in space, and insights into black holes. Research here has also paved the way for advancements in medical treatments and our understanding of the human body’s adaptation to extended space travel.

NASA has plans to keep the ISS operational until 2030. However, it will eventually need to be deorbited. When that time comes, the ISS will enter the mesosphere, where many components will meet the same fiery fate as meteoroids during reentry.

How Can You Spot the ISS?

Eager to catch a glimpse of this extraordinary structure? You can track the ISS as it flies overhead! Check NASA's website for sighting schedules in your area.

Stay curious! There’s much to discover about the cosmos and the marvels of technology that help us understand it better.