NASA's Messenger spacecraft has discovered what may be a recurring meteor shower on Mercury.
The spacecraft found a "halo of gases" in Mercury's exosphere, Phys.org reports. Scientists suspect the meteor shower may be associated with the Comet Encke, which also causes several yearly events on Earth.
The Messenger spacecraft observed seasonal calcium surges regularly over a 9-year period, suggesting a periodic meteor shower. The scientists reported that the amount of interplanetary dust on Mercury is abnormally high, and it may have come from a cometary debris field.
NASA scientists noted that the potential discovery is important because Mercury's environment hasn't been explored to much extent.