Introduction: Space Junk and Astronaut Belongings

When astronauts venture into space, they leave behind various items, including personal belongings and mission-related debris. But what becomes of this space junk when they return to Earth or when they don’t? This article delves into the fate of these items, both on the Moon and in orbit.

On the Moon: Historical Value Meets Trashed Junk

The Moon is home to a myriad of discarded items, ranging from discarded trash to historical artifacts. Unlike Earth, the Moon doesn’t have scavengers to reclaim or recycle anything. However, some of this junk holds significant historical value, making it a gateway to the past of space exploration. The Apollo missions alone left behind a variety of items, from sensors to tools, which astronauts consider as simple “trinkets” to bring home, often limited to a one-pound allowance per person.

Astronauts' Belongings: Storage and Disposition

Most astronauts are careful not to bring unnecessary items with them, as there’s limited space on the spacecraft. In general, their personal belongings remain on Earth, stored in family homes or in secure storage locations. This arrangement ensures that their loved ones can retrieve the items, although some astronauts write a last will and testament just in case the unexpected happens. Thankfully, all American astronauts returned safely, while a few Russian missions encountered tragedy. For example, the Apollo 1 crew and the Challenger and Columbia shuttle crews tragically perished during their missions, leaving behind their belongings, which were handled like any other legal disposition of personal effects.

Orbital Decay and Re-Entry: A Natural Orbit of the Earth

Typically, astronauts plan to return to Earth after missions, usually lasting less than a year. However, occasionally, an orbital decay can occur, which means the spacecraft gradually loses altitude. This is due to the slight friction of the exosphere—Earth's upper atmosphere—causing the ISS to slowly lose its speed and altitude. The station maintains its orbit via periodic boosts from the engine in the ZVEZDA module. Without these boosts, the ISS would eventually deorbit and re-enter the atmosphere, breaking up or tumbling as it falls.

In contrast, any item thrown from the ISS would not receive similar boosts and would fall to Earth much sooner. The atmosphere exerts significant friction on these objects, causing them to burn up, a process known as atmospheric re-entry. Even something as large as an elephant would experience this, leading to total combustion in the atmosphere.

Throwing an object to avoid re-entry would require ejecting it from Earth's gravitational field, a feat currently impossible. However, if you could, it would likely fall towards the sun due to the solar system's gravitational pull.

Conclusion: The Lasting Legacy of Astronautics

From the Moon to the ISS, the legacy of space exploration can be seen in the remains left behind. Whether it's a simple bag of lunar soil or the staggering feat of maintaining life in the hostile environment of space, each item tells a story of human endeavor and the complex web of life support systems that make life in orbit possible.