A large unidentified metal object has been stranded on a beach at Green Head, Western Australia, sparking theories on social media about what it might be. The Australian Space Agency (ASA) is investigating as it is most likely space debris from part of a rocket and initially advised those close to the site 250 kilometers (155 miles) north of Perth to steer clear as it couldn’t rule out the possibility it might be dangerous. The state’s fire department has since declared the object safe, but police are now guarding it to prevent damage that might hinder identification.
The object has a dome atop a cylinder around 2 meters (6.5 feet) in diameter and almost as high. The object’s arrival came shortly after much of Australia was treated to the sight of the Indian Space Research Agency’s Chandrayaan3 Moon mission looking rather comet-like as it flew over, leading to immediate speculation of a connection. The barnacles on the object suggest it has been in the sea longer so can’t have been a product of that particular launch. However, rocket stages from previous launches would have landed in the Indian Ocean, and the possibility this comes from one of them is the leading contender.
Less plausible ideas tossed up with more confidence than knowledge include a piece of the missing MH370 aircraft and part of an oil drilling rig.
Although widely described as metal, those who have moved it say it is light enough it may be mostly made of carbon fiber.
"We're pretty sure based on the shape and the size, it is an upper-stage engine from an Indian rocket that's used for a lot of different missions," European Space Agency engineer Andrea Boyd told Australia’s ABC.
India’s space program has ramped up in recent years, so it might be expected this had only been in the ocean a year or two, but Boyd is thinking much further back, suggesting it could be as much as 20 years old. "But at the same time,” Boyd added, “when it gets thrown around the ocean it does tend to look older than it would normally."
It's standard for engines from the first three stages to fall off, and for launches from India that usually means landing in the Indian Ocean. In the Atlantic or Pacific Oceans the currents on the south-eastern margin flow north because of the Coriolis force, which would sweep any debris away from Australia. However, the situation in the Indian Ocean is much more complex, and an object that got caught in the Leeuwin Current could easily end up running aground in Western Australia.
Dr Alice Gorman of Flinders University told The Guardian the third stage of the polar satellite launch vehicle rocket was most likely. “It’s surprising because it’s such a large fragment,” she said. “And it makes you wonder what was going on at the time.”
Under the UN’s Outer Space Treaty, the organization doing the launching is responsible for any space junk. However, like so much of international law, this rule suffers from the lack of anyone with the power to enforce it. When downed satellites or rocket parts do serious damage compensation is usually a fraction of the clean-up cost. Fortunately, such incidents have so far been rare, and it is more common for finders to want to keep the item as a memento.