A Soviet-era spacecraft meant to land on Venus in the 1970s is expected to soon plunge uncontrolled back to Earth. It’s too early to know where the half-ton mass of metal might come down or how much of it will survive re-entry, according to space debris-tracking experts. Dutch scientist Marco Langbroek predicts the failed spacecraft will re-enter about 10 May. He estimates it will come crashing in at 150mph (242km/h), if it remains intact. “While not without risk, we should not be too worried,” Langbroek said in an email. The object is relatively small and, even if it doesn’t break...