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A graveyard for spaceships 3900km southeast of Wellington has received its latest junk - a Russian Progress M-57 launch vehicle carrying rubbish from the International Space Station.
The ship undocked from the space station as normal and the parts that failed to burn up in Earth's atmosphere splashed into the Pacific Ocean about 4.15pm (NZT) on Wednesday.
The site is regularly used as the end point for supply flights to the orbital station. Believed to have been in use for the past 30 years, the cemetery is the final resting place for the remains of many spacecraft, including the defunct Mir space station.
When supply flights to the International Space Station unload fresh vegetables and fruit - plus about 2.5 tonnes of other food, water, fuel and equipment - the rubbish from the previous supply craft is loaded back into the cargo spaceship and dumped in the Pacific.
Matthew Pavletich, from the New Zealand Spaceflight Association, said the watery grave was the last stop for most Russian spacecraft.
The supply shuttles were usually launched from the Baikonur Cosmodrome, about 2100km southeast of Moscow in Kazakhstan.
The cosmodrome was also the launch site for Sputnik 1, the world's first artificial satellite.
"They [mission controllers] probably picked the area off Wellington because shipping is reasonably sparse," Mr Pavletich said.
"They do take some consideration as to the normal shipping lanes."
He said warnings were put out when the shuttles were to return to Earth.
"Now if you're a yachtsman just tooling around out there, you probably wouldn't want some space junk falling on your head," Mr Pavletich said.
While pieces from Russian spacecraft have been occasionally found in New Zealand, most of the craft burn up on re-entry. "They are normally made out of aluminium, sometimes stainless steel," he said.
"It's usually only the steel part that survives, unless they're particularly massive."
