But presently, as they were on the point of joining battle, with no apparent change of weather, but all on a sudden, the sky burst asunder, and a huge, flame-like body was seen to fall between the two armies. In shape, it was most like a wine-jar (pithos), and in color, like molten silver. Both sides were astonished at the sight, and separated. This marvel, as they say, occurred in Phrygia, at a place called Otryae.
Understandably, both sides decided this was an omen worth paying attention to, and called off the battle. (I guess there was no indication of who the omen was against, so they both decided to play it safe.) The delay didn't help Mithridates, ultimately; the Romans under Lucullus went on to fight on another day when there were fewer flaming wine-jars in the sky, and Pontus was resoundingly defeated.
So, what was this apparition?
Well, the likeliest answer is that it was a bolide -- a meteor that bursts in midair. It's understandable how in those highly superstitious times, when omens were detected even in the entrails of slaughtered animals, such an occurrence would have sparked quite a reaction.
An even stranger one is the tale of the "Airship of Clonmacnoise," an account of a sighting that occurred in around 740 C.E. near Teltown, in County Meath, Ireland. Here, the problem is sorting out what people actually saw from later embellishments. The earliest versions of this story simply state that several "flying ships with their crews" were seen in the skies, but very quickly it grew by accretion. In later iterations, the multiple ships coalesced into a single huge one, which was halted over the Abbey of Clonmacnoise when its anchor snagged on the roof of the abbey church. A "sky sailor" climbed down a rope ladder to free it (shades of the Goblin Ship in the most recent episode of Doctor Who!), and told the astonished monks he was "in danger of drowning in the thicker air of this lower world."
Here's an account from thirteenth century monk and scholar Gervase of Tilbury:
The people were amazed, and while they discussed it among themselves, they saw the rope move as if [the crew] were struggling to free the anchor. When it would not budge for all their tugging, a voice was heard in the thick air, like the clamor of sailors vying to recover the thrown anchor. Nor was it long until, hope in the effectiveness of exertion having been exhausted, the sailors sent down one of themselves – who, as we have heard, dangling from the anchor rope, came down it hand over hand. When he was about to disengage the anchor, he was seized by bystanders: he gasped in the hands of his captors like a man lost in a shipwreck, and died suffocated in the moisture of our thicker air. But the sailors overhead, surmising that their comrade had drowned, cut the anchor rope after having waited for an hour, and sailed away leaving the anchor.
Of course, it's worth mentioning that by now the scene of the incident had shifted to London, because there's no way a good Englishman like Gervase could let such an exciting tale take place in a remote spot like central Ireland.
This one is probably just a tall tale -- although I do find the bit about the air down here being "thicker" curious, because that certainly wasn't widespread knowledge back then.
Then we have the events of the morning of April 14, 1561, when "many men and women of Nuremberg" witnessed something very peculiar. The incident caught enough attention to be written up in a widely-circulated broadsheet the following week. Here's how it was described by the witnesses:
In the morning of April 14, 1561, at daybreak, between 4 and 5 a.m., a dreadful apparition occurred on the Sun, and then this was seen in Nuremberg in the city, before the gates and in the country – by many men and women. At first there appeared in the middle of the Sun two blood-red semi-circular arcs, just like the Moon in its last quarter. And in the Sun, above and below and on both sides, the color was blood, there stood a round ball of partly dull, partly black ferrous color. Likewise there stood on both sides and as a torus about the Sun such blood-red ones and other balls in large number, about three in a line and four in a square, also some alone. In between these globes there were visible a few blood-red crosses, between which there were blood-red strips, becoming thicker to the rear and in the front malleable like the rods of reed-grass, which were intermingled, among them two big rods, one on the right, the other to the left, and within the small and big rods there were three, also four and more globes. These all started to fight among themselves, so that the globes, which were first in the Sun, flew out to the ones standing on both sides, thereafter, the globes standing outside the Sun, in the small and large rods, flew into the Sun. Besides the globes flew back and forth among themselves and fought vehemently with each other for over an hour. And when the conflict in and again out of the Sun was most intense, they became fatigued to such an extent that they all, as said above, fell from the Sun down upon the Earth 'as if they all burned' and they then wasted away on the Earth with immense smoke. After all this there was something like a black spear, very long and thick, sighted; the shaft pointed to the east, the point pointed west.
Like the apparition that stopped the Roman/Pontic battle, this was interpreted as an omen -- in this case, that God was even more pissed off than usual, and everyone should immediately repent and promise not to be naughty hereafter. So once again, everyone interpreted what they saw based on their cultural context -- which, honestly, is pretty universal. But from a more scientific standpoint, what the hell was this?
Unlike the Airship of Clonmacnoise (or Teltown or London or wherever they finally decided it happened), it's hard to dismiss this one as a tall tale. The accounts are numerous, detailed, and -- most important, from a scientific standpoint -- all agree substantially with each other. Skeptic Jason Colavito says that he believes the account is consistent with the atmospheric phenomenon called sun dogs, in which high-atmosphere ice crystals cause light refraction when the Sun is low in the sky, creating two bright spots (sometimes with a rainbow sheen, and often with a partial or complete halo) on either side of the Sun.
The problem is, I've seen many sun dogs, and nothing about them moves -- they can be kind of eerie, but they just hover near the horizon and eventually fade. I've never seen a sun dog that "fell from the Sun down upon the Earth and then wasted away with immense smoke." So for me, this one is in the "unknown" column.
Perhaps the strangest of all is the event that happened in February of 1803 in the Hitachi Province of the east coast of Japan. Called Utsuro-bune (虚舟, hollow boat) the story was recorded in at least four separate written accounts. The story goes that fishermen saw a strange object drifting in the ocean, and upon approaching it, found that it was a peculiar vessel "shaped like an incense burner," about 3.3 meters tall by 5.5 meters wide. They said that the top half was "the color of lacquered rosewood," with windows made of glass or crystal, and the bottom half made of metal plates. They towed it to land, and found that inside was a very small (but apparently adult) woman, only about 1.5 meters tall, with pale pink skin and red hair with white tips. She spoke to them in some strange language, and could neither speak nor understand Japanese. She clutched a rectangular metal box covered with strange inscriptions, and wouldn't let anyone touch it.
Understandably, everyone in the area was pretty freaked out by this. After numerous unsuccessful attempts to communicate with her, or at least see what was inside the box, they gave up and decided she was too creepy to keep around. Ultimately, they put her back into her strange vessel, towed it back out to sea, and let it drift away.
UFO aficionados naturally are predisposed to interpret this as a Close Encounter with an alien. Certainly her odd appearance and tiny size make that explanation jump to mind. But can we infer anything more solid from it?
The story itself is strangely open-ended -- they never find out anything more about their weird visitor, and ultimately send her back to her dismal fate in the ocean. It hasn't the tall-tale aspects of the Clonmacnoise Airship story, nor the obvious astronomical explanation of the flaming wine-jars over Nicaea. Some have suggested that she was simply some poor soul -- possibly Russian or western European -- who had been cast adrift. Unfortunately, no one thought to copy the odd symbols inscribed on the metal plates of her craft; at least that'd give us information about whether we're talking about an object of terrestrial manufacture, or something more exotic.
Like the Nuremberg incident, this one was widely-enough recorded that it's hard to dismiss it entirely as a myth. But who the woman was, and where she'd come from, are still a mystery and probably always will be.
So there are four old tales that are widely touted in UFOlogical circles as evidence of visitation. Predictably, I'm not convinced, although I have to admit they're curious stories. But my reaction is tempered by the fact that "it's a peculiar tale" isn't enough to append, "... so it must be aliens." Before we jump to a supernatural or paranormal explanation, it's critical to rule out the natural and normal explanations first -- and, critically, to determine if there's even enough hard evidence to draw a conclusion.