Month: September 2019

Here’s why some people get bitten by mosquitoes more than others.

It’s true. Mosquitoes prefer biting some people over others and now scientists know why. As it turns out, about 20% of people are especially yummy to mosquitoes. Here’s why. Mosquitoes smell carbon dioxide Mosquitoes find victims by smelling carbon dioxide. They can smell it from across a large yard. People who exhale more carbon dioxide than others become targets. This is why children, who breathe smaller breaths, are bitten less often than adults. Mosquitoes prefer dark colors Just as we see with human beings, to a mosquito, certain colors stand out more than others. If you wear black, dark blue, or red, mosquitoes will swarm your way. Mosquitoes smell lactic acid Mosquitoes can also smell lactic acid, the chemical excreted when you exercise. They also are attracted to heat. Thus, sweaty

The absorption of light by blood experiment – an experiment with blood and colored lights.

The absorption of electromagnetic radiation happens all around us. In fact, this absorption process is the cornerstone for many modern-day technologies. Absorption of electromagnetic radiations allows the conversion of solar energy into electricity. The absorption of microwave electromagnetic radiation is what makes radars work. And our bodies absorb electromagnetic radiation too. Certain frequencies are absorbed easier by our bodies than others. In this experiment, we will demonstrate the body’s absorption of a common frequency range of electromagnetic radiation – visible light. In a darkened room, we will hold a red LED flashlight to our thumb. The thumb will glow bright red indicating much of the light passed right through our thumb. When we hold a green LED flashlight to our thumbs however, almost all of the light

Watch this Air Force test sled reach a mind boggling 6,599 miles/hour (Mach 8.6).

Hold on tight because this video shows a high-speed test at the Holloman Air Force Base in New Mexico that makes us think the Air Force should be designing roller coasters. The sled in this video reaches a dazzling speed of 6,599 miles/hour. That's Mach 8.6 for the science nerds.   The Holloman High Speed Test Track (HHSTT) is a United States Department of Defense/Air Force aerospace ground test facility located at Holloman Air Force Base in south-central New Mexico. According to the Air Force: "The Holloman High-Speed Test Track is a 10-mile long, precision-aligned track that provides scientists and engineers a platform from which to conduct their various missions. Tests on the track provide valid data on problems which cannot be solved by other ground test means." Sources:

Here’s what a flame looks like in space, where there is no gravity.

How a flame burns in space When a flame burns on earth, heated gases rise from the fire, drawing oxygen in and pushing combustion molecules out. As the flame burns, it heats the air around it and causes it to expand and rise upward. Denser air sinks downward to fill the void. The process continues in a sort of loop. This upward rising of air is what causes the classic teardrop shape we see in a candle flame. In microgravity however, hot gases do not rise. Air pretty much remains unmoved in all areas around the flame. So an entirely different process, called molecular diffusion, drives flame behavior and gives it an unusual round appearance. Since no flow of air replaces the oxygen that is burnt, only

Unable to find food in it natural habitat, this starving polar bear roamed into a town in Russia looking for food.

Residents of Norilsk, Russia woke to a strange site. A starving polar bear was roaming the streets looking for food. The animal would normally be in the Kara Sea area, about 300 miles from Norilsk, but climate change has forced animals such as this, to roam far from home looking for food and habitat they require to survive. The polar bear was photographed roaming throughout the city looking for food. Its paws are blackened with mud accumulated during its long trek. Authorities in the area say the polar bear may be sedated and transported to a zoo. World Wildlife Fund's Russia office told reporters: "It’s not normal for them to walk so far south, but the unusual situation can happen because of the lack of natural food and ice." The