The key to a birdhouse is not a manufacturer’s custom design but a simple box of the proper size. If you put up nest boxes of the proper dimensions, you will typically get a wren or a chickadee; a flicker or a red-bellied woodpecker; a screech owl; and perhaps a titmouse, for a usual maximum […]
The order of the colors in a rainbow from top to bottom are red, orange, yellow, green, blue, violet. However, if you see a double rainbow, with a larger but fainter secondary rainbow outside the main rainbow, the colors will be reversed in the second rainbow. A supernumerary rainbow, also also known as a stacker […]
What Did Ernest Rutherford Discover About Radioactive Bullets and Alpha and Beta Radiation From Uranium?
Ernest Rutherford agreed with Curie that radioactive rays came from the atom, but what was the nature of these subatomic rays? Rutherford’s early research would answer this question. He placed a tray of uranium near the poles of a magnet and placed a photographic plate beyond the magnet. The radiation particles moved quickly between the […]
Viruses attack living cells like soldiers taking over a factory. The processes a plant relies on to survive, like growth, metabolism and photosynthesis, take place in cells. Viruses can subvert the cells’ functions to their own ends, eventually killing the tissues that the cells make up. First, the virus attaches itself to the external wall […]
How Does Letting Red Wine Breathe Improve the Flavor and What Was the Original Reason For Decanting Wine?
Wine is left to breathe to allow the volatile and aroma-bearing substances to start evaporating, so that we may enjoy the bouquet. Shaking a drink is completely different. An agitated drink incorporates gas, letting oxygen reach as much liquid as possible. This oxidised liquid provides a very different taste. For some drinks this taste may […]
Polaroid photos are seemingly a magic trick, and in reality there is something of an illusion in the way it “develops before your eyes.” After you take an instant photo, it passes through two stainless-steel rollers, which spread chemicals that are collected in a blob at the edge of the plastic film sheet. These chemicals […]
There are two reasons why cookware may heat up excessively in a microwave oven. The first is the same effect that occurs in cooking: friction. Microwaves are rapidly fluctuating electromagnetic fields, which push on electric charges and twist naturally polarized particles like water molecules back and forth. In liquid water, this twisting leads to molecular […]
An eggshell may look solid and impermeable, but it has about 8,000 pores that are large enough for oxygen to flow in and carbon dioxide to flow out. It was John Davy of Edinburgh, Scotland, who proved this in 1863 by pumping pressurized air into an underwater egg and watching thousands of tiny bubbles float […]
There is a difference between kidney stones and gallstones. The “stones” that grow in each are related to what each organ does for the body. The gallbladder is a small sac that lies just below the liver. It holds bile that’s been produced by the liver, saving it until the stomach needs it to add […]
We all know water comprises just two chemical elements, oxygen and hydrogen, both of which exist as gases in Earth’s atmosphere. Making water should therefore be as simple as smashing the two together with enough force to overcome the energy barrier keeping them apart – right? However, this reaction produces a huge amount of energy, […]
Sorry, but yes. Not actual fragments, but individual molecules, molecules that have evaporated from the “stuff” and have floated through the air to your nose. But don’t get sick at the thought. It takes only an incredibly small number of molecules to be detected by humans as an odor. And the molecules aren’t even molecules […]
Oh, no, you don’t. This is one of those pointlessly endless questions with an answer that depends on how you define sound. If you define sound as “vibrations within a certain frequency,” then the answer is yes. If you define it as “something perceived by an ear,” then the answer is no. So to answer […]
Why Did Georges Cuvier Reject the Theory of Evolution and How Did Cuvier Show That Life Did Not Evolve?
Before Charles Darwin came up with his theory of evolution in 1859, biologists debated how to explain the similarity and diversity among animals, and Georges Cuvier was right in the middle of the debate. Cuvier was brilliant at anatomy, but he made the mistake of dismissing evolution. Both of France’s other leading biologists at the […]
What seems like frozen fingers is very subjective and could cover a wide range of temperatures. Having fingers that are icy cold is a real sensation and can be very distressing, but it is usually not reflective of something dangerous. What is more dangerous is where one finger is cold or has changed color, or […]
How Long Can a Cold Virus Or Any Other Pathogen Live On a Surface and Does Moisture Make a Difference?
How long a virus can live depends on the surface. Cool, moist glass in the shade, for instance, might retain many kinds of rhinovirus or coronavirus for days. Brass which is dry, sun-baked, and covered with verdigris and zinc compounds, on the other hand, might be germ-free within half an hour of being touched. Such […]
Ordinarily, water is the best mixer in the world, and I don’t mean just with Scotch. It mixes with, it associates intimately with, it even welcomes into its very bosom, that is, it dissolves, more substances than any other liquid. That’s why it is sometimes called the universal solvent. But there is one family of […]
Not just in Mexico, it’s been raining frogs all over the world for a long time now, if you believe the reports. And not just frogs either, but fish, periwinkles, crabs, jellyfish, coins, worms, baby alligators, and even ears of corn. These are not just stories from the tabloids; some have even been reported in […]
The United Nations keeps a registry and a data center at NASA assigns designations, but only communications satellites are subject to practical controls. Every satellite must be registered to a particular country, for reasons of liability under space law. A registry has been maintained by the UN Secretariat since 1962, and another registry, established under […]
“Killer bees,” properly known as Africanized honeybees, are not more poisonous than other honeybees. They are, however, much more aggressive than the gentle European honeybee when they feel threatened or encroached upon, and are more likely to kill people or animals by bombarding them and delivering multiple bee stings. There’s a reason behind this aggressiveness. […]
First of all, please don’t call air pressure “barometric pressure.” The air around us has a temperature that is measured by a thermometer, a humidity that is measured by a hygrometer, and a pressure that is measured by a barometer. Television weather reporters wouldn’t dream of talking about the air’s “thermometric temperature” or its “hygroscopic […]
Why Do Galaxies Collide and Move Toward Each Other If the Universe Has Been Expanding Since the Big Bang?
Galaxies can collide because the expansion of the universe is the expansion of space itself, not the movement of matter through space. Local movement is independent of this overall expansion. The Andromeda galaxy is actually moving towards us. The big bang was not like a normal explosion, in which fragments of a lump of matter […]
The wind-chill factors one commonly sees on earth are for turbulent flow, usually over exposed human skin, which loses heat by evaporation and convection. Laminar flow over smooth dry metal, which is what aircraft designers aim for, is much less efficient at transferring heat. At 29,500 feet, air density is about one-third of its value […]
If it were true that earthworms could grow back if cut in half, then worms could dispense with that messy sex business. Worm sex is messy, although pretty efficient. Worms are hermaphrodites, so they can mate with any other worm of their species (although not, as some would have you believe, with themselves). They do […]
Yes, in some cases. Kidney transplants were pioneered by the School of Veterinary Medicine at the University of California at Davis and are now performed at some other veterinary colleges around the country. They can cost $3,000 or more. There are no other transplant programs for dogs or cats, though there was initial research on […]
Iron plus oxygen plus water equals rust. That’s it. When all three are present, rust will inevitably occur. But if any member of this unholy triumvirate is missing, there can be no rust. Fortunately for us living creatures, but unfortunately for our garden tools and automobiles, oxygen and water vapor are present everywhere in the […]
The strength of what meteorologists call the updraft in a thunderstorm is what determines the size. A storm forms at a place in the atmosphere where the air is moving up very rapidly. When the air cools in the cold upper atmosphere, its water vapor condenses into a storm cloud. Eventually precipitation forms in the […]
I doubt that the ancient Greek philosophers spent much time on this (especially since they didn’t have coffee), but it’s a challenging question, if not an earthshaking one. You could settle it with an accurate thermometer, but you’d have to measure out exactly the same amounts of coffee and cream into exactly the same type […]
Despite anecdotal stories of athletes healing faster and pushing harder as a result, science has been unable to definitely prove that using anabolic steroids actually increases performance. As a matter of fact, because steroids are psychologically addictive drugs, most doctors believe that at least some of the positive effects are in the users’ minds. Anabolic […]
Glowworms are lightning bugs (or fireflies, if you prefer) during their larval stage. Glowworms can be found in many parts of North America in the summer. The best time to see them is at night or in the evenings.
First, we have to straighten out some terminology: • Penicillin (not penicillium) is the name of the drug. • Penicillium (not penicillin) is the genus of the mold that produces the drug. • Listeriosis and brucellosis are diseases caused by bacteria, not the names of the bacteria themselves. The drug. The oft-told story of the […]
You don’t lose fat cells when you lose weight, the fat cells simply become smaller. In people who have an excess number of fat cells, the fat cells may be even smaller than normal when they get down to a normal weight. That may be one reason it is so easy to regain weight. The […]
Batteries do not contain electricity as such; they contain the potential for electricity in the form of chemicals. These chemicals are isolated from one another inside the battery and are thus prevented from reacting until we hook up the battery to a device and turn on the switch. Then they react and produce electricity. Getting […]
Milk thistle does contain chemicals called flavones that appear to benefit the liver, but these compounds are not very soluble in water, and the tea has only about one-tenth the strength of the original plant material. In fact, the chemicals are poorly absorbed through the gastrointestinal tract and would probably be medically effective only if […]
Just pumping a spray of water into the air wouldn’t work very well, except perhaps in extremely cold weather. And by the way, the machines don’t produce actual snowflakes; they make tiny beads of ice, each one around ten thousandths of an inch in diameter. The simple spraying of water wouldn’t work because when water […]
Why Is Red Meat Red and White Meat White and What Is the Difference Between Red Meat and White Meat?
Red meat is red because the muscle fibers which make up the bulk of the meat contain a high content of myoglobin and mitochondria, which are colored red. Myoglobin, a protein similar to haemoglobin in red blood cells, acts as a store for oxygen within the muscle fibers. Mitochondria are organelles within cells which use […]
Farts are pretty flammable. Of the three main gases in fartsnitrogen, methane, and hydrogenmethane and hydrogen are both highly flammable. Nitrogen’s not. According to the statistics we found, over a quarter of the idiots who try lighting farts get burned. The rest are treated to a barely visible show of yellow and blue flames, as […]