Christmas Eve brought some celestial magic for hundreds of people across Germany and nearby countries. Eyewitnesses reported seeing between one and three glowing orbs in the night sky, with tails variously described as white, red, or green, depending on the location of the observer.
Some thought they might be seeing a UFO or, given the date and color scheme, Santa and his sleigh. But the biggest clue about the mysterious objects' identity came from the sequence of eyewitness reports: What they saw began as a large object that later broke into several smaller pieces, each with its own tail streaking out into an individual arc across the sky. This pattern is typical of objects re-entering Earth's atmosphere from orbit and burning up along the way. [ Video ]
Experts at first suggested that what was being seen was either a meteorite or orbital debris, colloquially known as space junk. There are tens of millions of pieces of space junk in orbit, though only a fraction of them would be large enough to have created the sight.
The mysterious light was eventually identified as a piece of spaceflight history: a famous Soyuz rocket. According to a statement issued by the Royal Observatory of Belgium, "The fireball observed above Belgium, the Netherlands, France and Germany on December 24 around 17h30 was the re-entry of the third stage of the Soyuz rocket that transported the Dutch astronaut André Kuipers to the [International Space Station]."
Adding credibility to this explanation: Santa delivered his gifts on time.
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Benjamin Radford is deputy editor of Skeptical Inquirer science magazine and author of Scientific Paranormal Investigation: How to Solve Unexplained Mysteries. His website is www.BenjaminRadford.com.