The term "20/20 vision" refers to how sharp your eyes are when you look at a standard eye chart (Snellen chart) from a distance of 20 feet (or 6 meters)—depending on where you live. In the United ...

Theta 1 and Theta 2 Orionis are two multiple-star systems within the Orion Nebula (M42). Theta1 includes several stars; the four brightest comprise the Trapezium star cluster at the heart of M42. To ...

Making time to catch the latest Netflix hit? Easy. Making time to visit the eye doctor? Surprisingly difficult. Enter: Online eye exams — because if you can do it from your couch, why wouldn’t you?

Please provide your email address to receive an email when new articles are posted on . The Hadassah Self-Visual Acuity Screener demonstrated high reliability, accuracy and alignment with standard ...