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.
Anything that blurs a child's vision or causes the eyes to cross or turn out may result in lazy eye. Common causes of the condition include: Muscle imbalance (strabismus). The most common cause of lazy eye is an imbalance in the muscles that position the eyes. This imbalance can cause the eyes to cross in or turn out, and prevents them from tracking together in a coordinated way. Difference in sharpness of vision between the eyes (refractive anisometropia).