Putting the Size of the Observable Universe in Perspective. The age of the universe is about 13.75 billion years. The diameter of the observable universe is estimated at about 28 billion parsecs (93 billion light-years). As a reminder, a light-year is a unit of length equal to just under 10 trillion kilometres (or about 6 trillion miles).
Red eye is the result of changes in the blood vessels in your eye that make your eye look red or bloodshot; it may occur in one or both eyes. Red eye is usually caused by irritation, infection or trauma. Even everyday causes, such as coughing, sneezing, crying, and lack of sleep, can lead to redness in your eye. Red eye is often accompanied by other eye symptoms, including burning, itching, soreness, tearing and discharge.
Causes of watery eyes. It is common to temporarily produce excess tears when you are emotional, laughing, coughing, vomiting, experiencing strong taste sensations, or yawning. One of the most prevalent reasons for watery eyes is dry eye syndrome. Extremely dry eyes can cause you to produce excess tears. If your tears do not contain enough of the right oils to lubricate your eyes, your eyes will continue to produce tears. Typically, watery eyes are temporary and resolve on their own when the cause is addressed or your eyes have healed. However, in some cases, the condition may persist.