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.
Nuclear sclerosis, also called lenticular sclerosis, can cause the pupils of your dogâs eyes to take on a cloudy bluish-gray appearance. The condition is also seen in humans and horses. This condition is a normal change to the lenses of the eyes that typically occurs in dogs over the age of six.