NASA/JPL Solar System Dynamics; Donald K. Yeomans. A dated table of reported naked-eye apparitions, with brightness, perihelion, and Earth-approach data. JPL notes that “Great” is subjective.
A note on the name
“Great” is a judgement, not a class.
Observers and historians use Great Comet informally for a comet that became unusually conspicuous. How impressive it appears depends on its activity, geometry, distance from Earth, sky darkness, and who was watching. NASA/JPL’s historical page calls the label subjective; this timeline uses it as context, not as a formal catalogue category.
A comet’s apparition is one observed visit through the inner Solar System. A periodic comet can return again: Halley, for instance, is the same comet seen in different apparitions. Most comets in JPL’s Great Comets table are not known to repeat on human timescales.
This is a curated, browsable selection chosen for historical documentation, visibility, or scientific importance—not a complete list of every notable comet, nor a claim to cover the whole internet. Dates in early records can vary between calendars and sources.
Ten passages through the record
A selective timeline
Search by year, name, designation, or a detail in the notes. Source links sit with each comet.
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Go a little deeper
A small research shelf.
A few useful starting points: a historical table, a specialist catalogue, and institutional background.
Gary W. Kronk’s specialist historical comet resource, now preserved and expanded by José J. Chambó. Browse past comets and periodic comets.
Gary W. Kronk’s six-volume Cambridge University Press book series is an important detailed catalogue. The publisher’s record lists Gary W. Kronk, Maik Meyer, and David A. J. Seargent among the authors.
NASA Science’s introduction to comet structure, activity near the Sun, tails, and selected comet missions and resources.
Reading historical records: ancient and medieval dates may be translated across calendar systems, and eyewitness brightness descriptions are not modern instrument measurements. Treat a source’s designation and context as part of the story; follow its references when precision matters.