Can you fly all the way around the world?

The Ultimate Race Around the World: Air vs. Space

Since the dawn of aviation, humans have been fascinated by the idea of circumnavigating the globe. In 1992, the iconic Concorde supersonic airliner made history by completing a global flight in just 33 hours. This remarkable feat remains a testament to the incredible speed and efficiency of atmospheric flight.

However, when compared to the realm of space travel, the Concorde’s journey seems like a leisurely stroll. The International Space Station (ISS), orbiting at an altitude of approximately 400 kilometers, can complete a global circuit in a mere 92 minutes. This stark contrast highlights the fundamental differences between air and space travel.

Speed: A Matter of Mechanics

The primary factor determining the speed of a flying object is its interaction with the surrounding medium. In the case of atmospheric flight, aircraft are subject to drag, a force that opposes their motion through the air. To overcome this resistance, aircraft require powerful engines that generate sufficient thrust to propel them forward.

In space, however, drag is virtually non-existent. The ISS moves through the near-vacuum of the Earth’s orbit, eliminating the need for excessive propulsion. Instead, its speed is primarily determined by the laws of orbital mechanics.

Orbits: The Key to Efficient Travel

Orbital motion is a delicate balance between two opposing forces: gravity and centrifugal force. Gravity pulls the ISS towards the Earth, while its tangential velocity creates a centrifugal force that keeps it from spiraling inward. This equilibrium results in a constant, elliptical path around the planet.

The ISS’s orbit, like most satellites, is not perfectly circular. Instead, it is slightly elliptical, with a closest point to Earth known as perigee and a farthest point known as apogee. As the ISS travels along its orbit, its altitude and speed vary slightly.

At perigee, the ISS is closest to Earth, experiencing the strongest gravitational force. This gravitational pull causes the ISS to speed up. As it moves towards apogee, the gravitational force weakens, and the ISS slows down. This variation in speed allows the ISS to maintain its elliptical orbit.

The Future of Circumnavigation

While suborbital flights and commercial space tourism are becoming increasingly accessible, the ultimate dream of a global flight in space remains a distant reality. The current technology for launch and re-entry vehicles is still too expensive and complex for regular passenger travel.

However, as space exploration continues to advance, it is possible that future spacecraft may be designed to circumnavigate the globe in a matter of hours. Such a feat would not only revolutionize travel but also provide unprecedented opportunities for scientific research and exploration.

For now, the Concorde’s 33-hour globe-trotting record remains the pinnacle of atmospheric flight. But as we look towards the future of space travel, it is clear that the limits of human ingenuity are yet to be fully tested.