The article “Comets as solar probes” by Karel Schrijver, Carey Lisse, and Cooper Downs (Physics Today, October 2013, page 27) was very enjoyable and informative. Readers might be interested in some additional examples of comets that have been observed close to the Sun.1 Obviously, in historical times these comets were only seen during total solar eclipses. The earliest comet observed traveling near the Sun was around 94 BC, “the comet that once was seen near the sun when the latter was eclipsed”; the record appears in Naturales quaestiones (7.20.4) by Seneca and in other classical sources.2
Several comets have been spotted near the Sun in the past two centuries. One example, observed during the eclipse on 17 May 1882, was the first comet photographed during a total solar eclipse.3 Another interesting case demonstrates the difficulties of interpreting astrophysical observations: A modern analysis showed that the coronal comet of 16 April 1893, reported by John Martin Schaeberle from Mina Bronces, Chile,4 was actually a disconnected mass ejection.5
