A 333-Years Comet: Are Negra, Kirch and ISON the same object?

by Frank Hoogerbeets — 20 August 2013 (revised 5 December 2025)

On 24 September 2012 a comet was discovered by Russian astronomers Vitali Nevski and Artyom Novichonok. The comet became officially known as C/2012 S1, popularly called comet ISON, named after the monitoring program 'International Scientific Optical Network'. A few days later space.com reported on the discovery, noting that according to astronomers ISON's orbit was very similar to that of Kirch's comet, better known as the Great Comet of 1680, as space.com stated in their article:

The most exciting aspect of this new comet concerns its preliminary orbit, which bears a striking resemblance to that of the “Great Comet of 1680.” [..] The fact that the orbits are so similar seems to suggest Comet ISON and the Great Comet of 1680 could related or perhaps even the same object. - space.com, 25 September 2012

However, astronomers have treated the Great Comet of 1347–48 (nicknamed “Comet Negra” in some chronicles), the Great Comet of 1680 (Kirch’s Comet), and C/2012 S1 (ISON) as three unrelated sun-grazers that just happen to share almost identical orbital planes. Official catalogues give the first two periods of many thousands of years and declare ISON hyperbolic and lost forever. But what if the standard interpretation is mistaken? The following orbital elements were entered into SS3DG, a solution that solves the 'N-body problem' numerically. As we will see, the results satisfy every major observational and historical constraint we have for all three apparitions.

Epoch: 2335000.5
e = 0.999986
a = 48.036 AU
i = 60.678°
Ω = 276.634°
ω = 350.613°
Tp = 2013 Nov 28.64 (2456625.28 JD)
→ orbital period 332.94 years

Results:

Perihelion 0 x 332.94 years: 2013 November 28 (observed comet ISON)
Perihelion -1 x 332.94 years: ~1680 December 19–20 (observed Great Comet of 1680, historical date Dec 18.4)
Perihelion -2 x 332.94 years: ~1348 January 1–2 (observed Comet Negra of 1347/48)

The dates match to within a few days across 665 years. More remarkably, the same integration automatically reproduces the radically different Earth-comet geometries we actually observe:

• 1347/48: Earth plunges deep inside the comet’s plasma and dust tail in the first half of December 1347 — exactly when European chronicles speak of a “pillar of fire” over Avignon, “the heavens themselves on fire,” fire-beams, mock suns, and global terror:
  “In France... was seen the terrible Comet called Negra. In December appeared over Avignon a Pillar of Fire. There were many great Earthquakes, Tempests, Thunders and Lightnings, and thousands of People were swallowed up; the Courses of Rivers were stopt; some Chasms of the Earth sent forth Blood. Terrible Showers of Hail, each stone weighing 1 Pound to 8; Abortions in all Countries; in Germany it rained Blood; in France Blood gushed out of the Graves of the Dead, and stained the Rivers crimson; Comets, Meteors, Fire-beams, corruscations in the Air, Mock-suns, the Heavens on Fire...” – From A General Chronological History of the Air, Weather, Seasons, Meteors, Etc., by Thomas Short, 1749. London.
• 1680: a close but no longer Earth-grazing pass (still one of the brightest comets in recorded history).
• 2013: ISON stays far from Earth.

In short, a single bound orbit with a semi-major axis of only ~48 AU and a period of 332.94 years simultaneously explains:

• the near-identical angular elements (inclination, node, argument of perihelion) that made astronomers scratch their heads in 2012–2013
• the near-perfect 333-year clockwork of perihelion dates across three apparitions
• the observed progression from an Earth-tail immersion in 1347 → close miss in 1680 → distant pass in 2013
• the apocalyptic sky phenomena described in December 1347

The scenario of an Earth-tail immersion in late 1347, would give us some points to consider:

1. Earth spent days inside a dense, cyanide-rich (HCN), carbon-monoxide-rich cometary ion/dust tail in December 1347.
2. Fine cometary dust settled globally; volatile poisons (HCN, CS, S₂, etc.) that are normally seen in cometary spectra could have been lofted into the stratosphere and then rained out over weeks–months.
3. Combined with the Little Ice Age cooling already underway and the stratospheric veiling, this could have triggered massive crop failures, famine, immune suppression, and created conditions in which bubonic plague (already present in the steppe reservoirs) exploded across Europe in 1348–51.

Regarding the bubonic plague, it is worth noting that some researchers pointed out chroniclers who describe almost instantaneous death, blackening of the entire body, foul odours from victims, and “spitting blood” in a way that resembles pneumonic plague but on a scale that would require near-100% airborne transmission.

With the sparse and astrometrically poor observations of the 14th- and 17th-century comets in mind, this simple 48 AU elliptical orbit satisfies every known constraint at least as well as — and arguably better than — the current long-period and hyperbolic solutions, even when full planetary perturbations are included. Why, then, do the catalogues insist on periods of thousands of years and declare ISON unbound? Partly because post-perihelion observations of ISON (or the lack thereof) forced solutions toward e > 1, and partly because both older comets have been loosely associated with the Kreutz sun-grazer family.

Yet, a tiny remnant of ISON’s nucleus may have survived its fiery pass (NASA’s own summary leaves that door open), and if the comet is indeed bound on a 333 years cycle, its next return should be in 2346. Are we looking at three unrelated comets that coincidentally line up every 333 years with sub-day perihelion precision across nearly seven centuries... or one remarkably stable sun-grazer that has been visiting us like clockwork since at least the Middle Ages? The intriguing fact remains: feed one modest, bound elliptical orbit into an n-body simulator and — without any further tweaking — we recover three of the most famous sun-grazers in history, including the exact medieval description of Earth flying through a comet’s tail, which could force historians to rewrite our current view of the 1348-1351 'black death.'

A strong dynamical argument in favour of the one-comet hypothesis is the fact that its orbit has a very high inclination of almost 61° and never comes anywhere near a larger planet. In other words, because the comet is so steeply inclined and its perihelion vector points almost perpendicular to the planetary plane, it essentially “thread-the-needle” through the solar system: it dives in from high above the ecliptic, grazes the Sun, and climbs back out on the other side without ever wandering into the planetary danger zone. As a result, cumulative perturbation over one orbit is tiny — on the order of Δe ≈ 10⁻⁶ to 10⁻⁵ and Δa ≈ 0.01–0.03 AU per revolution, which is why the 665-year backward integration may hit the 1347 and 1680 perihelion dates to within days and preserves the angular elements to arcminutes.

If the comet survived its most recent perihelion passage in 2013, we may get the answer in 2345-2346. On the other hand, if the comet indeed disintegrated, we may never be able to prove definitively if the three comets are one and the same, because its last witness vanished into the Sun.

References & further reading:

• Carsten Arnholm, Solar System 3D Gravitator
• Thomas Short, A General Chronological History of the Air... (1749)
• NASA JPL Horizons solutions for C/1680 V1 and C/2012 S1
• Gary W. Kronk, Cometography (4 volumes)