Why do the eyes of some animals tend to glow at night? Why don’t human eyes glow at night as well?
Well that has to do with a difference between a part of the eye of animals and of humans. At the back of the eye, we have a thin layer of light sensitive cells located on a tissue called the retina. These light sensitive cells, referred to as cone and rod cells, are what help us see light images. Cone cells help us see color and detail, while rod cells help us see shades of gray and motion.
When animals have eyes that glow at night, they have something behind their retina called a tapetum lucidum. This tapetum is a shiny reflective surface, almost like a mirror. It can amplify the amount of light that enters into the retina and reflect light that already entered through the retina, striking the light sensitive cells a second time. By doing this, nocturnal animals that hunt at night are able to see well in a dark environment.
Humans on the other hand have a tapetum negre, which absorbs excess light that enters through the retina.
Air is all around us and wherever there is air, there is air pressure. This means that everything (including us!) has pressure being applied on it.
Most objects (and us!) stay in their original shape because of internal pressure being exerted from within it. This creates an equilibrium system where internal pressure equals that of the external pressure.
What’s awesome is that if you take away external pressure, internal pressure will do whatever it can to create an equilibrium!
In this gif, an explainer is using a vacuum to remove air (external pressure) from within the chamber. Shaving cream has many air bubbles in it, so the air in the shaving cream (internal pressure) pushes outward and expands to create an equilibrium!
Maker Faire 2014 was held this past weekend at the NY Hall of Science. This activity was one of many that explainers discussed during the weekend! You can check out some pictures here!
Teenager from India invents device that can convert breath to speech
A high school student from India has invented a device that can convert a person’s breath into speech, to give millions of people around the world suffering from speech impediment a ‘voice’ for the first time.
Sixteen-year-old Arsh Shah Dilbagi has developed a new technology called ‘TALK’, which is a cheap and portable device to help people who are physically incapable of speaking express themselves. Right now, 1.4 percent of the world’s population has very limited or no speech, due to conditions such as Amyotrophic lateral sclerosis (ALS), locked-in syndrome (LIS), Encephalopathy (SEM), Parkinson’s disease, and paralysis.
His name is Arsh Shah Dilbagi and he’s 16 years old. Gettin tired of sensationalized “mystery baby from a country where people are brown does a science thing!” articles. Use peoples names, don’t act so surprised when people of color are geniuses.
This is brilliant!
Autumn equinox is arriving on September 23, 2014 at 2:29 (UTC). You can check the exact time in your area from here!
The autumn equinox is when the Earth has almost no tilt on its axis in regards to the sun. This means that both hemispheres of the Earth receive approximately the same amount of sunlight. You’ll notice that on equinox days, night and day are almost equal in length!
Get ready for sweater weather and foliage!
An end to plastic packaging poisoning us and all the life that feeds off the ocean is very very possible.
Independent packaging project for perishable goods:
Is it reasonable that it takes several years for a milk carton to decompose naturally, when the milk goes sour after a week? This Too Shall Pass is a series of food packaging were the packaging has the same short life-span as the foods they contain. The package and its content is working in symbiosis.
Gel of the agar agar seaweed and water are the only components used to make this package. To open it you pick the top. The package will wither at the same speed as its content. It is made for drinks that have a short life span and needs to be refrigerated, fresh juice, smoothies and cream for example.
Package made of biodegradable beeswax. To open it you peel it like a fruit. The package is designed to contain dry goods, for example grains and rice.
A package made of caramelized sugar, coated with wax. To open it you crack it like an egg. When the material is cracked the wax do no longer protect the sugar and the package melts when it comes in contact with water. This package is made for oil-based food.
Would you like to live to be 255 years old?
Well a giant tortoise can. One such animal named Adwaitya died at the Calcutta Zoo in India in 2006, and carbon dating proved him to be about 255 years old. This means that he has been roaming on earth since around the year 1750. But why are these species able to live for so long?
Giant tortoises have been on the planet even before the dinosaurs. These enormous land based creatures can weigh beyond 200 kilograms and their shells are more than a meter long. This shell provides the tortoise with immense protection. Unlike humans, tortoises have a very low metabolic rate, which means that they burn energy incredibly slowly. They are able to survive for long periods of time without food or water, allowing their growth process to be incredibly slow. For this reason, they do not age as fast. Their organs do not wear out as quickly.
Also, wild turtles live in harsh environments that create difficult conditions for breeding. They have an evolutionary advantage with their long life span, allowing more opportunities for them to procreate. Most tortoises have a strict vegetarian diet and are very peaceful, stress free creatures. These factors of calm and healthy living contribute to their long life span.
Have you ever wondered about those weird worm-like specks that drift into your vision, then keep reading.
Those squiggly lines usually show up when you look at something really bright like the blue sky, or a white piece of paper. Those guys are called floaters, and they’re actually just shadows. As the photo above can attest, there is a glob of jelly-like goo that fills up the interior of the eye called the vitreous humor. This is where the floaters are located.
The purpose of the vitreous humor is to help the eye to stay round, and to keep the retina flat against the back of the eye. When light focuses through the different parts of the eye like the cornea and the lens, it must also pass through that gel to get to the retina. The floaters, that form when proteins in the vitreous clump together, often get in the way of the light that is projected onto the retina. Once the light is blocked, a shadow will be cast, resulting in the cobweb-like bits we see.
We all have ‘em, but only about 70% of people actually pay attention to the floaters in their eyes. They’re always there, but your brain tends to ignore them because it’s gotten used to them. Y our brain is pretty good at seeing around the floaters, the same way it ignores the way your nose blocks your vision. It’s very rare, but there are some severe cases of eye floaties that require the vitreous humor to be extracted and then replaced with saline liquid.