Comet C/2012 S1, which astronomers also call Comet ISON, did not die after its close pass at the Sun two days ago. (Source: ABC News) Yesterday morning (Friday 29 November 2012) at 8:11 a.m. EST, an object appeared near the Sun on Comet ISON’s course track. ( Sources: CNN, ABC, Huffington Post) It grew a tail and already has a corona 1000 times the diameter of Earth. So Comet ISON has almost surely passed the Sun. It broke into a few large pieces instead of thousands of little pieces.
But more important than that, Comet ISON has been here before. A retired engineer notes that Comet ISON followed almost the same orbit as Comet C/1680 V1, the Great Comet of 1680. He told CNAV this afternoon, in no uncertain terms: Comet ISON and the Great Comet of 1680 are the same comet.
Comet ISON and its course track
This time-lapse image shows Comet ISON approaching and leaving during its slingshot around the sun – represented by the white circle — on Nov. 28, 2013. The ISON images clearly outline the curve of the comet’s orbit path. Images from SOHO.Photo courtesy of ESA/NASA/SOHO/SDO/GSFC
Comet ISON takes its name from the International Scientific Observation Network. It is one of several comets the ISON group observed and numbered. This particular comet, C/2012 S1, excited the ISON group members for an important reason, according to NASA: it seems to have come in on a hyperbolic orbit.
An object on a hyperbolic orbit would fall in toward the Sun, pass around it, leave the solar system, and never come back.
No astronomers have ever seen a comet fall in toward the Sun on a hyperbolic path. This fact has vexed astronomers who champion the favorite theory to explain where comets came from. In 1952, Jan Oort proposed that all comets come from a spherical “cloud of comets” that orbits the Sun as far out as fifty thousand times the distance from the Earth to the Sun. (That’s fifty thousand astronomical units.) A passing star perturbs the cloud and sends a comet or two falling in. So says the theory. (The only star that could do this would be Proxima, or Alpha Centauri C. Even that is too far away. But we digress.)
That no comet has ever fallen in on a hyperbolic track, is a deal-killer for the Oort cloud theory. Walter T. Brown of Phoenix, Arizona, points this out in his book, In the Beginning: Compelling Evidence for Creation and the Flood.
If passing stars or other gravitational disturbances “shake” comets from an Oort cloud, some of those comets should have obvious hyperbolic orbits as they enter the planetary region. None have been reported, so there is probably no Oort cloud.
This is true whether one believes the Oort cloud formed well beyond the solar system, or formed at its edge, only to have the gas giants sling them further out.
But Comet ISON is on a hyperbolic track. In fact, Comet ISON’s track seems to be hyperbolic beyond twelve standard deviations. If that holds, then Comet ISON came in from beyond the solar system, from even further away than 50,000 AU.
Or did it? Brown points out something NASA and every reporter on Comet ISON overlooks. No one really knows how heavy the solar system is. If the solar system is less than one percent heavier than people think, a comet like ISON does not even feel the full effect of its gravity until it is much further away. So Comet ISON, and any of a number of other “near parabolic comets,” can still follow a closed path. We simply wouldn’t see the far end of that path. And at the time of this writing, Comet ISON feels only the gravity of the Sun and not the gravity of any of the planets, satellites, or asteroids! (Reason: an object closer to the primary than other objects in orbit cannot feel the gravity of those other objects. Not until its own course track takes it outside their orbits again.)
One other reason makes a hyperbolic course track less likely. How could a comet, on a hyperbolic track, pass close enough to the Sun almost to skim its surface, and risk disintegration and death? That would be like shooting an arrow from Proxima (see above), or even Tau Ceti, and grazing the bulls-eye!
So if Comet ISON follows a closed path, then it is simply a long-period comet. And it almost surely has been near the Sun and the Earth before.
The Great Comet of 1680
On 30 November 1680, Comet C/1680 V1 passed within 0.0062 AU of the sun. (Brown describes this comet on this page.) On 29 December 1680 it became the brightest object in the sky. It was so bright that Europeans could see it in the daytime. Sir Isaac Newton saw it and developed his theory of gravitation in part by watching it move.
The problem: Comet ISON is following almost the same track as did Comet C/1680 V1. The chances that any two comets would follow orbits that are any closer than those of Comet ISON and C/1680 V1 are six thousandths of one percent. That is statistically significant, meaning it didn’t “just happen that way.” Those two comets follow the same course track for a reason.
What can that reason be? Either Comet ISON and the 1680 Comet are the same comet, or Comet ISON is a big piece of Comet 1680 that fell back to the Sun sooner than did the main mass. At least one amateur astronomer believes the latter. But where’s the rest of the 1680 comet in that case?
Brown explains it this way (and explained it again to CNAV): Comet C/1680 V1 sailed out beyond the furthest objects in the solar system after making its spectacular pass. In so doing, it came under the influence of all the Trans-Neptunian Objects.
They’re discovering new Trans-Neptunian Objects every week, it seems. [And] the distribution of the mass matters. If it’s a shell, you need more mass to pull the comet back in. If it’s a disk, you need less, because more of that mass will pull it in as it passes it.
So: we don’t know how massive the solar system it. And if Comet ISON is the same as Comet C/1680 V1, then the period of that comet is 333 years. So before 1680, it was probably another unrecognized event during the Hundred Years War in Europe. Before that it was an unnoticed or unrecorded event in the era of the Crusades. Perhaps the Chinese have a record of it, but no one has yet discovered or interpreted it properly.