The Soviet cosmonaut Yuri Gagarin became the first man in space when he made a full orbit of Earth in Vostok I on April 12, 1961. Although he was in space less than two hours, he became an international hero.
The United States launched the first American into orbit on February 20, 1962: Astronaut John Glenn completed three orbits of Earth in Friendship 7, traveling about 81,000 miles (130,329 kilometers).
The largest muscle is the buttock muscle (gluteus maximus), which moves the thighbone away from the body and straightens out the hip joint. It is also one of the stronger muscles in the body. The smallest muscle is the stapedius, in the middle ear.
It is thinner than a thread and 0.05 inches (0.127 centimeters) in length. It activates the stirrup that sends vibrations from the eardrum to the inner ear. The longest muscle is the sartorius, which runs from the waist to the knee. Its purpose is to flex the hip and knee.
Today’s computers contain millions of transistors placed in a tiny piece of sili- 162 con, some so tiny that they can fit in an ant’s mouth. The transistors (devices that control the flow of electric current) are packed and interconnected in layers beneath the surface of the chip, which is used to make electrical connections to other devices. There is a grid of thin metallic wires on the surface of the chip.
This silicon chip was independently co-invented by two American electrical engineers, Jack Kilby and Robert Noyce, in 1958–1959. The chip, along with the invention of the microprocessor, allowed computers to get smaller and more efficient. Silicon chips are also used in calculators, microwave ovens, automobile radios, and video cassette recorders (VCRs).
An earthquake is a great shaking of Earth’s surface. It is caused by the cracking and shifting of the plates of rock that make up the planet’s layered crust. As shifting plates suddenly slide past one another, vibrations in the form of waves are released. These shock waves travel through Earth, gradually weakening as they move farther from the spot (or spots) where the quake began, which is called the epicenter. Regions located near faults (places where cracks in Earth’s crust are known to exist), are particularly vulnerable to earthquakes.
Earthquakes vary in size and intensity. They may last a few seconds or continue for a few minutes. They may cause no damage, or they can result in widespread destruction and the deaths of thousands of people. Earthquake vibrations can be so violent that they collapse bridges and buildings, destroy highways, cause landslides, and lead to flooding if they occur in shallow water near a coast.
James Spangler, a janitor at an Ohio department store who suffered from asthma, invented his “electric suction-sweeper,” in 1907 as way of picking up the dust and debris that triggered his health condition. His invention was the first practical domestic vacuum cleaner. It used an electric fan to generate suction, rotating brushes to loosen dirt, a pillowcase for a filter, and a broomstick for a handle.
Because it was heavy and hard to handle, Spangler sold the rights of his invention to his relative, William Hoover, whose redesign of the appliance coincided with the development of the small, high-speed universal motor, in which the same current (either AC or DC) passes through the appliance’s rotor and stator. This gave the vacuum cleaner more horsepower, higher airflow and suction, better engine cooling, and more portability than was possible with the larger, heavier induction motor. Hoover’s model has since been refined, but the mechanics of his vacuum cleaner are still used in vacuum cleaners today.
Many volcanoes occur near the area where two ridges or plates of Earth’s crust meet. Circling the Pacific Ocean—where crust plates meet—is a group of volcanoes known as the Ring of Fire. Plate movement in such regions may allow liquid rock, called magma (it’s called “lava” only after it rises to the surface), that is located in chambers in Earth’s interior to rise, resulting in volcanic activity. (Such conditions often result in earthquakes as well.)
Volcanic activity can take place under the ocean as well as on land, and when this happens the formation of islands sometimes results.
1. On average, a man spends about five months of his life shaving.
2. On average, a hair strand’s life span is five and a half years.
3. On average redheads have 90,000 hairs. People with black hair have about 110,000 hairs.
4. Next to bone marrow, hair is the fastest growing tissue in the human body.
5. In a lifetime, an average man will shave 20,000 times.
6. Humans have about the same number of hair follicles as a chimpanzee has.
7. Hair will fall out faster on a person that is on a crash diet.
8. The longest human beard on record is 17.5 feet, held by Hans N. Langseth who was born in Norway in 1846.
9. The average human head weighs about eight pounds.
10. The reason why some people get a cowlick is because the growth of their hair is in a spiral pattern, which causes the hair to either stand straight up, or goes to a certain angle.
11. The reason why hair turns gray as we age is because the pigment cells in the hair follicle start to die, which is responsible for producing “melanin” which gives the hair colour.
12. The fastest growing tissue in the human body is hair.
13. A lifespan of an eyelash is approximately 150 days.
14. A survey done by Clairol 10 years ago came up with 46% of men stating that it was okay to color their hair. Now 66% of men admit to coloring their hair.
15. The big toe is the foot reflexology pressure point for the head.
16. The average human scalp has 100,000 hairs.
17. The first hair dryer was a vacuum cleaner that was used for drying hair.
18. Ancient Egyptians used to think having facial hair was an indication of personal neglect.
19. The loss of eyelashes is referred to as madarosis.
20. Hair and fingernails are made from the same substance, keratin.
21. Eyebrow hair lasts between 3-5 months before it sheds.
22. A Russian man who wore a beard during the time of Peter the Great had to pay a special tax.
23. Everyday approximately 35 meters of hair fiber is produced on the scalp of an adult.
24. Hair is made from the same substance as fingernails.
25. Brylcreem, which was created in 1929, was the first man’s hair product.
NASA’s space shuttle, also called the Space Transportation System (STS), takes off from Earth like a rocket but lands like an aircraft. It cannot fly to the Moon, but is used to orbit Earth, where the crew can do scientific work, place satellites in orbit, and visit orbiting space stations. Usually five to seven crew members ride the space shuttles, which have all been launched from Kennedy Space Center in Florida. Six shuttles have been built: the first orbiter, Enterprise, was built in 1974 for testing purposes. Five others have gone into space: Columbia, Challenger, Discovery, Atlantis, and Endeavour.
The space shuttle Challenger disintegrated 73 seconds after launch in 1986, and Endeavour was built as a replacement. Columbia broke apart during re-entry in 2003. NASA announced that the space shuttle would no longer be used after 2010, and from 2014 on would be replaced by the Orion, a new space vehicle that is designed to take humans to the Moon and beyond.
Absolutely. Being bitten by a plant-eating dinosaur such as Brachiosaurus, with its 52 chisel-like teeth, would certainly hurt! The bite of a Parasaurolophus, with its interlocking rows of teeth, might take off your fingers. In the Iguanodon, numerous sharp teeth were set in rows in the upper and lower jaws, and at steep angles to each other.
When the teeth were pressed together, the upper jaw was forced outward, creating a grinding motion between the teeth and its meal of crushed plant tissue.
Yes. The air inside your home might be filled with toxins from tobacco smoke, cleaning products, ceiling tiles, and upholstery. Scientists have discovered that many types of houseplants absorb airborne pollutants as part of their normal “breathing” process—they take carbon dioxide in through their leaves, and let oxygen out. The plant transports these toxins to their roots, where microbes feed on and detoxify them.
Although scientists disagree about how many—and what types of—houseplants it takes to clean the air, they suggest using a mix of plants. Bill Wolverton, a former NASA scientist and environmental engineer, studies the effects that plants have on air quality and has rated the areca palm, lady palm, bamboo palm, rubber plant, and dracaena as highly effective at clearing pollutants from the air.