Here is one of many detailed accounts, this one is from Dr. José Maria de Almeida Garrett, professor at the Faculty of Sciences of Coimbra, Portugal
I was looking at the place of the apparitions, in a serene, if cold, expectation of something happening, and with diminishing curiosity, because a long time had passed without anything to excite my attention. Then I heard a shout from thousands of voices and saw the multitude suddenly turn its back and shoulders away from the point toward which up to now it had directed its attention, and turn to look at the sky on the opposite side.
It must have been nearly two o'clock by the legal time, and about midday by the sun. The sun, a few moments before, had broken through the thick layer of clouds which hid it, and shone clearly and intensely. I veered to the magnet which seemed to be drawing all eyes, and saw it as a disc with a clean-cut rim, luminous and shining, but which did not hurt the eyes. I do not agree with the comparison which I have heard made in Fatima---that of a dull silver disc. It was a clearer, richer, brighter colour, having something of the luster of a pearl. It did not in the least resemble the moon on a clear night because one saw it and felt it to be a living body. It was not spheric like the moon, nor did it have the same colour, tone, or shading. It looked like a glazed wheel made of mother-of-pearl. It could not be confused, either, with the sun seen through fog (for there was no fog at the time), because it was not opaque, diffused or veiled. In Fatima it gave light and heat and appeared clear-cut with a well-defined rim.
The sky was mottled with light cirrus clouds with the blue coming through here and there, but sometimes the sun stood out in patches of clear sky. The clouds passed from west to east and did not obscure the light of the sun, giving the impression of passing behind it, though sometimes these flecks of white took on tones of pink or diaphanous blue as they passed before the sun.
It was a remarkable fact that one could fix one's eyes on this brazier of heat and light without any pain in the eyes or blinding of the retina. The phenomenon, except for two interruptions when the sun seemed to send out rays of refulgent heat which obliged us to look away, must have lasted about ten minutes.
The sun's disc did not remain immobile. This was not the sparkling of a, heavenly body, for it spun round on itself in a mad whirl. Then, suddenly, one heard a clamour, a cry of anguish breaking from all the people. The sun, whirling wildly, seemed to loosen itself from the firmament and advance threateningly upon the earth as if to crush us with its huge and fiery weight. The sensation during those moments was terrible.
During the solar phenomenon, which I have just described in detail, there were changes of colour in the atmosphere. Looking at the sun, I noticed that everything around was becoming darkened. I looked first at the nearest objects and then extended my glance further afield as far as the horizon. I saw everything an amethyst colour. Objects around me, the sky and the atmosphere, were of the same colour. An oak tree nearby threw a shadow of this colour on the ground.
Fearing that I was suffering from an affection of the retina, an improbable explanation because in that case one could not see things purple-colored, I turned away and shut my eyes, keeping my hands before them to intercept the light. With my back still turned, I opened my eyes and saw that the landscape was the same purple colour as before.
The impression was not that of an eclipse, and while looking at the sun I noticed that the atmosphere had cleared. Soon after I heard a peasant who was near me shout out in tones of astonishment: "Look, that lady is all yellow!"
And in fact everything, both near and far, had changed, taking on the colour of old yellow damask. People looked as if they were suffering from jaundice, and I recall a sensation of amusement at seeing them look so ugly and unattractive. My own hand was the same colour. All the phenomena which I have described were observed by me in a calm and serene state of mind, and without any emotional disturbance. It is for others to interpret and explain them.
Please read the post before voting on the comments, as this is a game where voting works differently.
Warning: the comments section of this post will look odd. The most reasonable comments will have lots of negative karma. Do not be alarmed, it's all part of the plan. In order to participate in this game you should disable any viewing threshold for negatively voted comments.
Here's an irrationalist game meant to quickly collect a pool of controversial ideas for people to debate and assess. It kinda relies on people being honest and not being nitpickers, but it might be fun.
Write a comment reply to this post describing a belief you think has a reasonable chance of being true relative to the the beliefs of other Less Wrong folk. Jot down a proposition and a rough probability estimate or qualitative description, like 'fairly confident'.
Example (not my true belief): "The U.S. government was directly responsible for financing the September 11th terrorist attacks. Very confident. (~95%)."
If you post a belief, you have to vote on the beliefs of all other comments. Voting works like this: if you basically agree with the comment, vote the comment down. If you basically disagree with the comment, vote the comment up. What 'basically' means here is intuitive; instead of using a precise mathy scoring system, just make a guess. In my view, if their stated probability is 99.9% and your degree of belief is 90%, that merits an upvote: it's a pretty big difference of opinion. If they're at 99.9% and you're at 99.5%, it could go either way. If you're genuinely unsure whether or not you basically agree with them, you can pass on voting (but try not to). Vote up if you think they are either overconfident or underconfident in their belief: any disagreement is valid disagreement.
That's the spirit of the game, but some more qualifications and rules follow.
If the proposition in a comment isn't incredibly precise, use your best interpretation. If you really have to pick nits for whatever reason, say so in a comment reply.
The more upvotes you get, the more irrational Less Wrong perceives your belief to be. Which means that if you have a large amount of Less Wrong karma and can still get lots of upvotes on your crazy beliefs then you will get lots of smart people to take your weird ideas a little more seriously.
Some poor soul is going to come along and post "I believe in God". Don't pick nits and say "Well in a a Tegmark multiverse there is definitely a universe exactly like ours where some sort of god rules over us..." and downvote it. That's cheating. You better upvote the guy. For just this post, get over your desire to upvote rationality. For this game, we reward perceived irrationality.
Try to be precise in your propositions. Saying "I believe in God. 99% sure." isn't informative because we don't quite know which God you're talking about. A deist god? The Christian God? Jewish?
Y'all know this already, but just a reminder: preferences ain't beliefs. Downvote preferences disguised as beliefs. Beliefs that include the word "should" are are almost always imprecise: avoid them.
Additional rules: