Planet Mercury's Comet-like Tail (sodium spectrum-view)

Planet Mercury's Comet-like Tail (sodium spectrum-view)

Planet Mercury's Comet-like Tail (sodium spectrum-view)Astrophotographer Steven Bellavia: "A 24 million km long plume of gas is ejected from Mercury's thin atmosphere due to the sun, very much like a comet. This is only visible using a narrowband filter that captures the bright yellow sodium light at 589nm. A tail was predicted in the 1980s, and first discovered in 2001. Multiple observations by NASA's robotic MESSENGER spacecraft that orbited M…