In 2007, researchers at the University of CaliforniaâDavis determined that our Solar System was fully formed at 4.568 billion years ago. They did this by determining the age of stony materials from the asteroid belt.
When to see a doctor. See your doctor immediately if you experience the signs and symptoms of migraine with aura, such as temporary vision loss or floating spots or zigzag lines in your field of vision. Your doctor will need to rule out more-serious conditions, such as a stroke or retinal tear.
Alcohol can affect the ability of the eyes to focus on the same object and also causes blurring of the vision. In other cases it can cause tunnel vision. Hallucinogenic drugs can have the same effect as alcohol, by causing damage to the eyes or the visual processing centers in the brain. The tunnel vision caused in these circumstances may be temporary or last for the duration when the drug is still in circulation.