The Orion spacecraft from NASA’s mission undergoes reentry. Image credit: NASA/Orion Spacecraft
Fact Fun revisits one of space exploration’s most breathtaking feats: the fastest speed humans have ever traveled in space, clocked at 39,937.7 km/h (24,816.1 mph) during Apollo 10’s fiery return to Earth in May 1969.
Apollo 10: The Sonic Dress Rehearsal
Apollo 10 launched on May 18, 1969, as a full-scale test flight ahead of the first Moon landing. Commander Thomas Stafford, astronaut John Young, and Lunar Module Pilot Eugene Cernan performed a complete lunar orbit. The LM, nicknamed “Snoopy,” descended to just 14 km above the lunar surface before returning to dock with the Command Module, “Charlie Brown.”
On May 26, as the crew re-entered Earth’s atmosphere, Apollo 10 reached a record-breaking speed of 39,937.7 km/h—still the fastest speed humans have ever traveled in space.
Why That Speed Was Possible
During reentry, spacecraft gain tremendous velocity. Gravity accelerates them toward Earth while atmospheric drag slows them down. The balance of these forces creates conditions that can produce extreme speeds. For Apollo 10, the reentry profile and returning from lunar distance made this high velocity achievable.
The spacecraft faced immense friction and heat—conditions that push both human physiology and engineering to their limits. Yet, the Apollo 10 crew endured it successfully, cementing their place in the annals of human spaceflight.
Could We Go Even Faster?
While modern spacecraft like the Space Shuttle and capsules such as Dragon or Soyuz reach speeds around 28,000 km/h in low Earth orbit, none have matched Apollo 10’s return speed. Deep-space probes like Voyager or Parker Solar Probe have far exceeded it—but they’re unmanned.
As of now, Apollo 10 remains the unmatched record-holder for the fastest speed humans have ever traveled in space.
Did You Know?
Even though astronauts have reached nearly 40,000 km/h, Earth itself orbits the Sun at roughly 108,000 km/h. On a grander scale, our solar system zips through the galaxy at over 700,000 km/h. But for human passengers aboard a spacecraft, Apollo 10 still holds the top spot.
Curious how science pushes human limits? Fact Fun uncovers the speed records, mysteries, and marvels of space and beyond. Bookmark us to ride the next wave of cosmic discoveries!
ref : BBC Science Focus
