⏱️ 6 min read
Since humanity first gazed at the stars, we’ve dreamed of venturing beyond our atmosphere. What began as science fiction has transformed into one of our greatest achievements. From the first satellites to modern space stations, space travel has revealed extraordinary truths about our universe and challenged our understanding of what’s possible. The journey beyond Earth’s atmosphere has been filled with surprising discoveries, incredible engineering feats, and phenomena that defy everyday experience.
Remarkable Discoveries from Beyond Earth’s Atmosphere
1. Astronauts Grow Taller in Space
One of the most surprising physical changes that occurs during space travel is that astronauts can grow up to 3% taller while in orbit. Without gravity compressing the spine, the vertebrae spread apart, causing the spinal column to elongate. This means an astronaut who is 6 feet tall on Earth could gain approximately 2 inches in height during an extended mission. However, this growth is temporary—astronauts return to their normal height within a few months of returning to Earth as gravity once again compresses their spine.
2. The International Space Station Travels at 17,500 Miles Per Hour
The International Space Station (ISS) orbits Earth at a staggering speed of approximately 17,500 miles per hour, completing a full orbit around our planet every 90 minutes. This means astronauts aboard the ISS experience 16 sunrises and sunsets every single day. At this velocity, the station could travel from New York to Los Angeles in less than 10 minutes. The incredible speed is necessary to maintain orbit—moving fast enough that as the station falls toward Earth due to gravity, it continuously misses the planet, creating a perpetual state of freefall.
3. Space Has a Distinctive Smell
Astronauts who have performed spacewalks consistently report that space has a distinct odor that clings to their spacesuits when they return to their spacecraft. The smell has been described as a combination of hot metal, welding fumes, and seared steak. Scientists believe this unique aroma comes from polycyclic aromatic hydrocarbons—high-energy particles that are byproducts of dying stars. These molecules attach to the suit’s exterior during spacewalks and are then released when astronauts return to the pressurized environment of their spacecraft.
4. There’s No Sound in the Vacuum of Space
Despite what Hollywood movies suggest, space is completely silent. Sound requires a medium such as air or water to travel through—it works by creating vibrations in molecules that transfer energy from one place to another. Since space is a near-perfect vacuum with virtually no molecules to vibrate, sound waves cannot propagate. This means that even the most powerful explosion would be completely silent in space. Astronauts must rely on radio communications, which use electromagnetic waves that don’t require a medium to travel.
5. A Full NASA Spacesuit Costs More Than $12 Million
The Extravehicular Mobility Unit (EMU), commonly known as the spacesuit, is one of the most expensive pieces of equipment ever created. Each suit costs approximately $12 million to manufacture, though NASA’s total investment including development exceeds $250 million per suit. These remarkable garments are essentially individual spacecraft, protecting astronauts from temperature extremes ranging from -250°F to +250°F, providing oxygen, removing carbon dioxide, maintaining pressure, and shielding wearers from harmful radiation and micrometeorite impacts. The gloves alone cost around $100,000 per pair due to their complex construction requiring both protection and dexterity.
6. Crying in Space Creates Floating Water Bubbles
Tears behave very differently in microgravity than they do on Earth. Without gravity to pull tears down a person’s face, they instead pool around the eyes in a ball of liquid. If enough tears accumulate, they can break free and float away as wobbly spheres of water. Astronauts report that crying in space can be uncomfortable because the tears don’t clear away naturally, and the liquid can even sting. This phenomenon isn’t just a curiosity—it has helped scientists better understand fluid dynamics in microgravity, which is crucial for managing water and other liquids in space.
7. The Footprints on the Moon Will Last for Millions of Years
The footprints left by Apollo astronauts on the lunar surface will remain virtually unchanged for millions of years. Earth’s footprints disappear quickly due to wind, rain, and geological activity, but the Moon has no atmosphere, no wind, and no weather to erode these marks. The only processes that will eventually affect them are micrometeorite impacts and the extremely slow accumulation of space dust. This means that Neil Armstrong’s first footprints from 1969 are still as crisp today as they were over 50 years ago, serving as an enduring testament to humanity’s achievement.
8. You Cannot Whistle in a Spacesuit
The atmospheric pressure inside a spacesuit is significantly lower than on Earth’s surface—approximately 4.3 PSI compared to 14.7 PSI at sea level. This reduced pressure is necessary to allow astronauts to move their arms and legs without excessive effort against the suit’s resistance. However, this lower pressure also means there aren’t enough air molecules to create the sound waves necessary for whistling. The same principle applies to other pressure-dependent activities, which is why spacesuits require specialized engineering to balance mobility, safety, and functionality.
9. A Day on Venus is Longer Than Its Year
While this fact relates to planetary science discovered through space exploration, it reveals one of the most bizarre discoveries from our ventures beyond Earth. Venus takes approximately 243 Earth days to complete one rotation on its axis, but only 225 Earth days to orbit the Sun. This means a Venusian day is actually longer than its year. Additionally, Venus rotates in the opposite direction to most planets, meaning the Sun rises in the west and sets in the east. This discovery has helped scientists understand planetary formation and the complex gravitational interactions in our solar system.
10. Astronauts’ Fingernails Fall Off in Space Gloves
One of the lesser-known hazards of spacewalking is the damage inflicted on astronauts’ fingernails. The pressurized gloves required for spacewalks create constant pressure on the fingertips, and the repetitive gripping and flexing during manual work can cause significant trauma. This often results in fingernails becoming bruised, damaged, or even falling off entirely. The condition is so common that some astronauts have deliberately injured their fingernails before missions or even had them permanently removed to avoid the problem. NASA continues to research improved glove designs to prevent this painful occupational hazard.
The Continuing Journey
These ten remarkable facts demonstrate that space travel is filled with surprises that challenge our earthbound assumptions. From the physical changes astronauts experience to the strange behaviors of everyday phenomena in microgravity, each discovery expands our understanding of the universe and our place within it. As space agencies and private companies continue pushing the boundaries of exploration, we can expect many more fascinating revelations about the final frontier. These insights not only satisfy our curiosity but also drive technological innovations that benefit life on Earth, proving that the quest to explore space remains one of humanity’s most worthwhile endeavors.