InterestingFacts: You Can See Inside Your Own Eye

 

Original photo by Andriiii/ Shutterstock

You can see inside your own eye.

Your eyes are how you see the world, but they’re also how you see yourself — including inside of your own eye. You may have experienced this while having your eyes examined, such as when the doctor shines a light on your pupils. When light comes from a small point and hits your eye just right, you can see your own blood cells as they move through the capillaries on your retina. The light reflects off the vessels, casting a shadow onto the light-sensitive cells in the retina and rendering them visible to your brain in a pattern of orange or red coloration. Each heartbeat sends those blood cells surging, adding a rhythmic quality to this strange phenomenon. 

You may also have experienced what’s called the blue field entoptic phenomenon while staring at the clear blue sky and noticing clear, floating cells moving through your field of vision. Unlike red blood cells, white blood cells don’t absorb the short wavelength of the blue light, allowing you to see them as they flow through the blood vessels in front of the retina. These are different from floaters (small spots that move through your field of vision), which tend to increase with age as the vitreous fluid in your eye changes thickness. In most cases, floaters are a normal aspect of aging, though in excess they could be a sign that you should have your eyes checked.


Note:  The above comes directly from their website.

Comments

Post a Comment

Popular posts from this blog

HistoryFacts: Nine Cities Have Served As America's Capital

Image
  F rom 1776 to 1800, the United States capital bounced around between  nine different cities . This frequent relocation was due to a mix of safety concerns amid the American Revolutionary War and a lack of a bureaucratic infrastructure in one centralized place. Philadelphia served as the nation’s first capital (at the time, the capital was considered to be the city where Congress met and enacted legislation) after the adoption of the Declaration of Independence on July 4, 1776. But due to safety concerns regarding a potential British attack on the city, Congress relocated to Baltimore, Maryland, on December 20, 1776, and the seat of government remained there for just over two months.  Congress returned to Philadelphia in March 1777, but fled once again due to the British occupation of the city that September. Delegates retreated further into Pennsylvania, settling in Lancaster for a single day on September 27, 1777, and then moving to York. After the British army departe...
Read more

InterestingFacts: Americal's First Theme Park was Focused on Santa Claus

Image
America's first theme park was focused on Santa Claus. In most cities, Christmas comes once a year… unless you live in Santa Claus, Indiana, the self-proclaimed home of the holiday season and America’s first theme park: Santa Claus Land. While amusement parks have  existed in the U.S. since the 1840s , at the beginning the general idea was just having fun. It wasn’t until 1946, with Santa Claus Land’s opening, that amusement parks  began developing specific themes . The attraction took advantage of the town’s unique name, hoping to draw in visitors who wanted to experience a bit of holiday spirit any time of year, and especially youngsters keen to meet St. Nick himself. Owner Louis Koch, who built the theme park as a retirement project, planned the destination with children in mind; his original park featured a toy shop, doll displays, children’s rides, and a restaurant. Over time, Koch also added a mini circus, deer farm, wax museum, and live entertainment. But Santa Claus La...
Read more

InterestingFacts: It's Technically Impossible to be "Double-Jointed"

Image
  It’s technically impossible to be “double-jointed.” Growing up, many people encounter that one friend who seems to be especially flexible — thumbs curve back, limbs jut out at awkward angles, and legs bend with unparalleled pliability. While this contortionist act is often said to be the result of being “double-jointed,” such a medical  diagnosis doesn’t actually exist . Instead, a large portion of humanity is  best described  as having “hypermobility” or “joint laxity.” This means that some people are born with loose ligaments or other bone oddities that make them more flexible than most. For the majority, hyperflexibility isn’t harmful, but a small percentage — those with  joint hypermobility syndrome  — can experience pain. So in the end, all humans have the same number of joints, but as for the tautness of our ligaments? Well, that’s a different story. Note:  The above comes directly from the Interesting Facts website.
Read more