Ring around the sun
A ring around the sun is a 22-degree halo, made by ice crystals in thin, high clouds. It needs a cloud veil that is just right (a clear sky shows none, a thick layer hides it), so only a slightly imperfect sky lets it appear.
What it may mean
A sun halo needs exactly the right sky. In a perfectly clear blue there is nothing to see, and under heavy gray cloud the sun itself is hidden. Only a thin, milky layer of high cloud, made of millions of tiny six-sided ice crystals, bends the light into that wide, pale ring. The halo is a gift of a slightly hazy day. Life has its own version: a small difficulty that reveals something a perfectly smooth week would have hidden, a minor disagreement that lets you see how a friend really feels, a delay that leads you to a better route. Weather lore also took halos as signs of coming rain, and it is often right, since such high clouds frequently run ahead of a warm front. People have read the ring in other ways too, from the sun sitting in his house to good harvests.
Depending on how you saw it
A halo with bright spots on either side
Sometimes two bright patches (sun dogs) glow on the ring's left and right, level with the sun. They form when flat ice crystals drift horizontally in the air. Which unexpected pair of helpers appeared on either side of a hard week of yours?
Measuring the ring with your hand
Stretch your arm and spread your fingers: the span from thumb tip to little finger covers roughly the halo's radius, about 22 degrees. Keep your eyes off the sun itself while you do it. Which large-looking thing in your life fits in one hand once you measure it calmly?
A reddish inner edge
A halo is often tinged red on the inside and fades to white outward. The tint is faint because the crystals are not all alike. Which side of a situation have you been reading backward?
A ring around the sun before rain
Cirrostratus, the cloud that makes halos, often arrives ahead of a warm front, and rain or snow may follow within a day or so. It is a useful clue, not a guarantee. What early clue in your week deserves preparation without worry?
Why it happens in nature
A 22-degree halo forms when sunlight passes through six-sided ice crystals in thin cirrus or cirrostratus clouds several miles up, which bend the light by about 22 degrees. These high clouds often move in ahead of a warm front, so a halo is a fair but imperfect sign of rain or snow within a day or so. Never stare at the sun itself while watching one.
What folk beliefs say
Zuni (Southwest)
The Zuni said that when the sun is in his house, inside a halo or circle, it will soon rain.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 1014. View the page
Ancient India
Among the signs of rain in the ancient Hindu astrological work Brihat Samhita: if the halos around the sun and moon looked bright and clear, there would be rain and the crops would thrive.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 977. View the page
To reflect on
Which small difficulty this week has shown you something a smooth week would have hidden?