The Tropic of Cancer and The Tropic of Capricorn. The Tropic of Cancer and the Tropic of Capricorn each lie at 23.5 degrees latitude. The Tropic of Cancer is located at 23.5Â° North of the equator and runs through Mexico, the Bahamas, Egypt, Saudi Arabia, India, and southern China.
Dr. Elliot Werner: Neither. Halos indicate something in the transparent structures of the eye that is interfering with the transmission of light back to the retina. The most common causes of halos are corneal edema (swelling), cataract, and high humidity in the air.
Corneal opacities are eye problems that can lead to scarring or clouding of the cornea, which decreases vision. The cornea is the clear, dome-shaped area that covers the front of the eye. Light passes through the cornea before reaching the retina in the back of the eye, and so it must remain clear so light can pass through. Corneal opacities can cause anything from minor irritation to vision problems and even blindness.