My Science School

An airship is a sausage-shaped balloon filled with a lighter-than-air gas that makes it float. The early airships could carry passengers across the Atlantic, but they were slow and dangerous because they were filled with hydrogen gas which burns easily. Modern airships are filled with safe helium gas, but they are still slow.

The first successful airship was constructed by Henri Giffard of France in 1852. Giffard built a 160-kilogram (350-pound) steam engine capable of developing 3 horsepower, sufficient to turn a large propeller at 110 revolutions per minute. To carry the engine weight, he filled a bag 44 metres (144 feet) long with hydrogen and, ascending from the Paris Hippodrome, flew at a speed of 10 km (6 miles) per hour to cover a distance of about 30 km (20 miles).

In 1872 a German engineer, Paul Haenlein, first used an internal-combustion engine for flight in an airship that used lifting gas from the bag as fuel. In 1883 Albert and Gaston Tissandier of France became the first to successfully power an airship using an electric motor. The first rigid airship, with a hull of aluminum sheeting, was built in Germany in 1897. Alberto Santos-Dumont, a Brazilian living in Paris, set a number of records in a series of 14 nonrigid gasoline-powered airships that he built from 1898 to 1905.

The most-successful operator of rigid airships was Ferdinand, count von Zeppelin, of Germany, who completed his first airship, the LZ-1, in 1900. This technically sophisticated craft, 128 metres (420 feet) long and 11.6 metres (38 feet) in diameter, had an aluminum frame of 24 longitudinal girders set within 16 transverse rings and was powered by two 16-horsepower engines; it attained speeds approaching 32 km (20 miles) per hour. Zeppelin continued improving his designs through World War I, when many of his airships (called zeppelins) were used to bomb Paris and London. Airships were also used by the Allies during the war, chiefly for antisubmarine patrol.

In the 1920s and ’30s, airship construction continued in Europe and the United States. A British dirigible, the R-34, made a round-trip transatlantic crossing in July 1919. In 1926 an Italian semirigid airship was successfully used by Roald Amundsen, Lincoln Ellsworth, and General Umberto Nobile to explore the North Pole. In 1928 the Graf Zeppelin was completed by Zeppelin’s successor, Hugo Eckener, in Germany. Before it was decommissioned nine years later, it made 590 flights, including 144 ocean crossings. In 1936 Germany inaugurated a regular transatlantic passenger service with the dirigible Hindenburg.

Despite these achievements, airships were virtually abandoned in the late 1930s because of their cost, their slow speed, and their intrinsic vulnerability to stormy weather. In addition, a succession of disasters—the best known probably being the explosion of the hydrogen-filled Hindenburg in 1937—coupled with advances in heavier-than-air craft in the 1930s and ’40s made dirigibles commercially obsolete for most applications.

Credit : Britannica 

Picture Credit : Google

It is an aircraft that can land and take off from water. The underside of the plane is shaped like a boat. Each wing has a float underneath to keep the plane balanced in the water. Some, called amphibians, have wheels and can be used on land or on water.

Ascending into common use during the First World War, flying boats rapidly grew in both scale and capability during the Interwar period, during which time numerous operators found commercial success with the type. Flying boats were some of the largest aircraft of the first half of the 20th century, exceeded in size only by bombers developed during the Second World War. Their advantage lay in using water instead of expensive land-based runways, making them the basis for international airlines in the interwar period. They were also commonly used as maritime patrol aircraft and air-sea rescue, particularly during times of conflict. Flying boats such as the PBY Catalina and Short Sunderland played key roles in both the Pacific Theater and the Atlantic of the Second World War.

The popularity of flying boats gradually trailed off during the Cold War era, partially because of the investments in airports during the conflict that eased the introduction of larger, and faster, land-based airliners. Despite being largely overshadowed, limited use of the type continued with some operators, such as in the case of the Shin Meiwa US-1A and the Martin JRM Mars. In the 21st century, flying boats maintain a few niche uses, such as dropping water on forest fires, air transport around archipelagos, and access to undeveloped areas. Many modern seaplane variants, whether float or flying boat types, are convertible amphibious aircraft where either landing gear or flotation modes may be used to land and take off.

Picture Credit : Google

The Russian major Yuri Alexeyevitch Gagarin became the first man to fly in space on April 12th 1961. His spaceship Vostock orbited the Earth for 108 minutes before returning.

He was killed at the age of 34 in 1968 when the MIG-15 jet trainer he was flying crashed.

The first cooperative human space flight project between the United States and the Soviet Union took place in 1975. The Apollo-Soyuz Test Project was designed to test the compatibility of rendezvous and docking systems for American and Soviet spacecraft and to open the way for future joint manned flights.

Since 1993, the U.S. and Russia have worked together on a number of other space flight projects. The Space Shuttle began visiting the Russian Mir space station in 1994, and in 1995 Norm Thagard became the first U.S. astronaut to take up residency on Mir. Seven U.S. astronauts served with their Russian counterparts aboard the orbiting Mir laboratory from 1995 to 1998. The experience gained from the Mir cooperative effort, as well as lessons learned, paved the way for the International Space Station.

In-orbit construction on the Station began in November 1998, and it has been staffed non-stop with international crews since November 2000. The first Station crew, made up of U.S. commander Bill Shepherd and cosmonauts Yuri Gidzenko and Sergei Krikalev, was launched on board a Russian Soyuz spacecraft. The crew returned to Earth on the Space Shuttle Discovery in March 2001.

Credit :  NASA

Picture Credit : Google

An ellipse is a geometric shape that results from viewing a circular shape in perspective, or from a different vantage point.  In simple terms, an ellipse is an oval.  Depending on the vantage point of the viewer, an ellipse results from the distortion of an object that is circular in shape.

As a geometric element, an ellipse has many definitions. As artists, we need not get too concerned with the mathematic elements of an ellipse.  We simply need to know how to draw one accurately. 

First we'll look how an ellipse works.  As mentioned before, an ellipse is the result of viewing a circular object from any vantage point other than "straight on".  Since there are many objects that are circular in shape, ellipses will be used quite frequently in our drawings and paintings.

Any circular shape can cause issues for an artist. It can be difficult at times to create smooth curvatures that are evenly balanced. For this reason, we can use a few methodologies to help us draw ellipses to a higher degree of accuracy.

To draw a perfect oval or ellipse, stick two pins through a paper covered board. Join them with a thread that is longer than the distance between the pins. Put a pencil in the thread, keep it tight and draw an ellipse.

Credit : The Virtual Instructor 

Picture Credit : Google

A science about the movement, distances and sizes of the Sun, Moon, stars, planets, meteors, constellations and comets within our and other solar systems.

Thousands of years ago some groups of stars were given names because their shape was similar to a bear, a dog, a lion or perhaps a plough!

Astronomers aren’t stargazers. Or, at least, there’s no longer any need for them to be. If you think an astronomer treks up mountains to spend night after night behind the eyepiece of a giant telescope, think again. These days telescopes can be controlled remotely, so it’s common for modern astronomers to simply make requests for observations and then download computer-generated data and images the next morning for their analysis. That includes space telescopes like the Hubble Space Telescope.

People very often confuse astronomy with astrology. Every professional astronomer has had to hear someone say to them, "so you’re an astrologer, right?" Astrology and astronomy are not the same thing, but they used to be. Observational astronomy can be traced back to Ancient Egypt and Mesopotamia as far back as 3,000 B.C., but the calculating of solar eclipses, the movements of the planets and theories about how the night sky works was the job of ancient astrologers who presumed that celestial events and alignments had a direct impact on human affairs. 

Modern astrologers attempt to do something similar, making predictions about human lives based on pseudoscience. Astrology is not a science. 

Credit : Space 

Picture Credit : Google

Mount Everest at 8,848m (29,028ft) is the highest mountain above sea level. The Island of Hawall, however, is the top of a mountain, Mauna Kea, which is 9,150m (30,000ft) high from its undersea base.

The first ever recorded people to climb Everest were Edmund Hillary (a mountaineer from New Zealand) and his Tibetan guide Tenzing Norgay. They climbed the mountain in 1953 and hold the record together. The first records of Everest’s height came much earlier, in 1856. British surveyors recorded that Everest was the tallest peak in the world in their Great Trigonometrical Survey of the Indian subcontinent.

The Himalayan mountains have long been home to indigenous groups living in the valleys. The most famous of these are the Sherpa people. The word “Sherpa” is often used to mean mountain guide, though it actually refers to an ethnic group. The Sherpa have valuable experience in mountain climbing, which they can provide to other climbers. Most climbs of Everest would be impossible without the Sherpas’ logistical help and knowledge. However, their way of life extends beyond helping Everest climbers. Traditionally, their lifestyle has consisted of farming, herding, and trade. And, because they live at such a high altitude year round, they are accustomed to the low oxygen levels.  

Climbing Mount Everest has become a popular expedition for mountain climbers. However, it is a dangerous undertaking. Climbing Everest requires a lot of experience mountaineering elsewhere, as well as a certificate of good health, equipment, and a trained Nepalese guide. The snow and ice on the mountain create deadly hazards like avalanches, and there is only a limited climbing season due to bad weather conditions. But perhaps the biggest danger is the altitude. Most climbers are not accustomed to the high altitude and low oxygen levels and rely on bottled oxygen they bring along. This is why the area above 8,000 meters (26,000 feet) elevation on Everest is called the “death zone.” Climbers who spend long periods in this region can develop altitude sickness and even brain swelling.

Mount Everest’s climbing industry has become controversial. As popularity of the climb has increased, there have been more “traffic jams” as climbers spend too much time in the death zone waiting for their chance to go to the summit. With more people has also come more pollution up near the summit as climbers often discard unwanted items all along the mountain. Additionally, the Sherpa people have been exploited by climbers, and their traditional way of life has been disrupted by foreign climbers. Sherpa guides are faced with some of the highest death rates of any field of employment, for comparatively little pay. Most disturbingly, because many climbers have died along the way, and their bodies are impossible to retrieve, climbers must frequently travel past corpses as they make their way up the mountain.

Credit : National Geographic 

Picture Credit : Google

On a small isolated island in the south eastern Pacific are scattered about 1,000 giant statues. Some weigh up to 90 tonnes and are 9.5m (32ft) tall. No one really knows how the Polynesians carved or raised these statues.

The island’s population represents the easternmost settlement of a basically Polynesian subgroup that probably derived from the Marquesas group. The original Rapa Nui vocabulary has been lost except for some mixed Polynesian and non-Polynesian words recorded before the Tahitian dialect was introduced to the decimated population by missionaries in 1864. Today Spanish is generally spoken. In their traditions, the islanders consistently divide themselves into descendants of two distinct ethnic groups, the “Long-Ears” and the “Short-Ears” (see below). Intermarriage is common, and an influx of foreign blood has become increasingly dominant in recent years.

Whereas the aboriginal economy was based on the cultivation of sweet potato, chicken raising, and coastal fishing, the island has shifted to a cash economy based on tourism. The opening of an airport at Mataveri near Hanga Roa has permitted an increasing influx of tourists since the 1960s, and a few small hotels have been built in the village area, where many islanders and settlers from continental Chile also have accommodations in their homes. The ties to continental Chile are strengthened through twice-weekly flights from Santiago and the building of schools, hospitals, and a large community hall for sports and performances. A well-organized Chilean national park system provides guided tours and security for the unique archaeological monuments. Reforestation projects have been successfully initiated, including eucalyptus plantations at Vaitea and coconut groves in Anakena Bay.

Credit :  Britannica 

Picture Credit : Google

Lapland is a region mainly inside the Arctic circle. It stretches across the north of Norway, Sweden and Finland.

This is the land of the Midnight Sun, which shines continually for 24 hours a day, for 73 days from mid-May to the end of July.

Lapland is a region of great topographical variety. To the west it embraces the northern part of the Kolen Mountains, which reach elevations of more than 6,500 feet (2,000 metres). On its Norwegian (western) side this range slopes abruptly and is deeply eroded into fjords and headlands and fractured into archipelagoes. The eastern flank of the range, which is situated in Swedish Lapland (see Lappland), slopes more gradually into a broad piedmont studded with large, fingerlike lakes that feed the rivers flowing into the Gulf of Bothnia. Farther to the east, Finnish Lapland (Lappi) is a relatively low-lying region with many bogs and small lakes.

Norwegian Lapland is largely open and windswept, with timber growth only in sheltered tracts and the more protected interior. Southern and central Lapland occupies the zone of the taiga, or swampy coniferous forest, with its saturated land and many bogs and swamps. Forests of pine and spruce give way to the dwarf birch, heath, and lichens of the tundra farther north and at higher elevations.

Many of the Sami have adopted a sedentary life and intermarried with Scandinavians and Finns. The region is still home to several hundred thousand reindeer, but the traditional reindeer country has been intruded upon by permanent farming, forestry, mining, and hydroelectric and even industrial enterprises. Those who practice reindeer herding have liberty of movement across the open boundaries of Finland, Norway, and Sweden.

Credit :  Britannica 

Picture Credit : Google