2000 SG344 (also written 2000 SG344) is a small Aten asteroid discovered in 2000. It has a diameter of 37 m and an estimated mass of 7.1×107 kg (71,000 tonnes). The object could also be classified as a meteoroid, although the most common definition uses a diameter of 10 m as the demarcation. Because of its very Earth-like orbit and the fact that it would have been near the Earth in 1971, it is thought that 2000 SG344 might actually be a man made object such as an S-IVB booster stage from a Saturn V rocket.
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