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Sharpen Your General Knowledge

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Shamim Ansary:
Do Cats Eyes Really Shine In the Dark?

Have you ever walked into a darkened room and seen a cat staring at you with its eyes blazing?

Scary, but beautiful! There are no lights in a cat’s eyes. What you see is simply a reflection of light.

A cat’s eyes are no different than yours in responding to light. In bright light, you both have pupils which narrow to reduce the glare. And at night, your pupils and a cat’s pupils open wide to let in all the available light, thus permitting you to see in dim light.

But a cat’s eyes shine in the darkness because this light which is let in is reflected by a layer of cells in its inner eye. This layer of cells, the tapetum, is pink, gold, blue, or green. When the outside light changes, the tapetum acts like a mirror and reflects a different color.

This reflecting process gives cats an amazing ability to see in the dark, approximately seven times better than the ability of people.

Most cats have blue, green, yellow or orange irises in their eyes, but some cats have two different-colored eyes!

Shamim Ansary:
Why Do Some People Put Pennies On the Eyes of Dead People and Where Did the Practice Come From?

Putting pennies on dead people’s eyes could have been used by many cultures to keep the eyes of the dead shut until rigor mortis sets in.

Some cultures, including the ancient Egyptians and more modern African Americans, have also used coins on the eyes and hands of the deceased to share with relatives in the spirit world or to pay for admittance into eternity.

In some Old World cultures, coins were used to keep the eyes shut for a specific reason: so that the living couldn’t see their own death in the eyes of the deceased.

Today keeping the eyes of the dead closed is more for aesthetic reasons than any other, especially since “viewing the body” has become commonplace.

Coins are rarely used, however. Nowadays, morticians employ one of two methods.

One is to use a device called an eye cap, which resembles a contact lens and actually fits over the eyeball. On the other side there are tiny “grippers” that keep the lids shut.

The other method is to place a thin line of adhesive on the lids to keep them shut.

Shamim Ansary:
What Are the Advantages of the Hubble Space Telescope?

The Hubble doesn’t have a mirror as large as the new Earth-based telescopes, but being in space it is not limited by the distortions caused by variations in the refractive index of air above the telescope.

In addition, a space telescope can detect the infrared and ultraviolet rays blocked by Earth’s atmosphere.

Other space-based telescopes are designed to detect X rays and gamma rays from extremely energetic stars and galaxies.

Shamim Ansary:
Where Did the Idiom “the Eleventh Hour” Come From and What Does the Phrase for the Last Minute Mean?

The reference is to the eleventh hour on the original clock devised by the Babylonians for use with their sundial.

The period from dawn to sundown, when a sundial was usable, was divided into twelve hours, so the eleventh hour came just before sunset.

In other words, if you did something at the eleventh hour, it was just before you ran out of daylight.

You’ll find this notion used metaphorically in Matthew 20:1-16.

From it we learn that even a sinner can find salvation at the last minute, even someone who procrastinates and doesn’t do what he has to do until, well, the eleventh hour.

Shamim Ansary:
How Do Stars Move Across the Universe and Why Do Stars Move Across the Sky at Night?

Traditionally, people have thought of the stars as immovable and permanent, but they do move.

We know the stars move because we know that the universe is expanding.

But Earth is also moving in the expanding universe, so the movement of the stars is imperceptible, you can’t see it.

“Wait a minute,” you might say. “I can see the stars move across the sky every night. They rise in the east and set in the west, just like the Sun.”

Just like the Sun, however, the stars only seem to move because Earth is rotating on its axis.

We are the ones who are moving relative to the stars.

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