Abstract
Ultraviolet measurements made by Voyager 2, apparently showing a rapid decrease in hydrogen Lyman-α emission with distance from the Sun, were taken by Donahue et al.1 as evidence for a source of atomic hydrogen in the very local interstellar medium (VLISM). The suggested source1 is a class of small comets, at solar distances of ˜1 AU, that produce atomic hydrogen as their icy mantle is evaporated. This claim has been adduced as evidence for a theory2 that the Earth is subject to a large influx of cometary material, significantly affecting atmospheric evolution. Here we analyse again the Voyager 2 data, and show that no source of hydrogen in the VLSIM is required other than the inflow of neutral atoms; the original analysis was apparently flawed by an erroneous transcription of tabulated data (T. M. Donahue, personal communication).
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
