Surprise as nickel vapour is found in comet tails far too cold for metal sublimation

Polish astronomers have identified nickel vapour in the tail of the comet 2I/Borisov – an interstellar comet spotted passing through the solar system in 2019 – even though the temperature was far too low for the sublimation of nickel.¹ The researchers suspect, therefore, that the nickel was released from photodissociation of compounds. Independent observations by Belgian astronomers identify similar gaseous nickel, in cold solar system comets, suggesting a possible organometallic origin.² The two papers together, therefore, could suggest a shared organic chemistry between different planetary systems.