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How far is Eris from Earth?

One of the largest dwarf planets known today, Eris was discovered in 2005. It measures approximately 1,864 miles in diameter, making it slightly larger than Pluto, and its orbital period is about 557 years. Its discovery led to Pluto's declassification as a planet.\n\nEris was discovered by Chad Trujillo, Mike Brown and David Rabinowitz during examinations of images of the Kuiper Belt taken at the Palomar Observatory in 2003. It is named after Eris, the Greek goddess of discord and strife. The name has proven to be apt because of Eris's place at the center of debate concerning the de..

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How long does a hurricane last?

There are hurricanes on record that have lasted as long as 31 days. In this case, it was Typhoon John, which formed in the Pacific Ocean in the 1994 season. Alternately, Hurricane Ginger in the Atlantic lasted 28 days from the day it formed in 1971. Most hurricanes do not persist for anything near these durations, often petering out well before they make landfall. Those that do make landfall often break up or are downgraded within days.

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What is the bright star in the evening sky?

Sirius is actually a binary star; its companion is a white dwarf near the size of the sun called Sirius B. The recording of Sirius dates back to at least ancient Egypt, where it was known as "Sopdet" and was a major feature of the Egyptian calendar. Its first annual heliacal rising signaled the beginning of the flood season for the Nile River Delta.

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What are tar pits?

Tar pits are extremely sticky, and animals are unable to escape from the asphalt when they fall in. Fossils have been discovered in tar pits around the world. The few known tar pits in the world include Tierra de Brea, Carpinteria Tar Pits, La Brea Tar Pits, McKittrick Tar Pits and Lake Bermudez.

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In which country was boron discovered?

All three chemists discovered boron by reacting boric acid with another element, possibly magnesium or potassium. Their samples were about 60 percent pure and produced a solid that the French chemists saw as gray and Davy called dark olive. A 99 percent pure boron sample was later isolated in 1909 by Ezekiel Weintraub, an American chemist who used hydrogen to reduce boron halides.

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What are some of the adaptations of a Labrador tea plant?

A prominent Labrador tea plant adaptation is its fuzzy, curled leaves that enable it to squeeze moisture from the air in cold, alpine environments. The fuzzy leaves also help to prevent water loss. For instance, the undersides of the leaves have fine hairs, and when the pores in the leaves open to pull carbon dioxide from the air, the hairs keep the plant from losing water. The leaves are adapted to the cold weather by curling, which minimizes exposure to wind.\nAnother adaptation of the Labrador tea plant deals with its ability to sprout from its roots. As fires are common in its natural habi..

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What are the differences between bacteria and viruses?

Bacteria are prokaryotic cells; their DNA is not contained within a nucleus. Bacteria are among the oldest life forms on Earth, with fossils dating back billions of years. Not all bacteria are harmful, and most are not. Some bacteria are photosynthetic and are responsible for contributing the majority of the Earth's oxygen. Other bacteria are extremophiles and exist in habitats unsuitable to most other forms of life. Still other bacteria are necessary to human survival and exist naturally in human digestive systems. Among bacteria that are harmful, the Mayo Clinic points out diseases such..

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How does a drum produce its sound?

Drums are one of the oldest instruments known to humans. Little is required to construct a drum, making it exceptionally easy for ancient civilizations to create and use.\nA basic drum consists of two parts: the tightly stretched membrane covering the top of the drum (the head), and the hollow casing underneath. When the head of a drum is struck, it vibrates and moves air around it, creating sound waves. Normally, the sound would be somewhat dull and quiet, no matter how tightly stretched the head. However, the hollow body, beneath the head, amplifies the sound by creating a miniature echo cha..

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How often does a high or low tide occur?

At high tide, water covers much of the shore; at low tide, the water recedes, and much of the shore lies bare.\nBoth the sun and moon pull at the Earth; however, the moon exerts a more powerful influence because it is much closer to the Earth. This is called the tidal force. The part of the Earth that faces the moon experiences high tide – as does the opposite side of the Earth away from the moon. The areas between the regions of high tide have low tides.

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What is bulk flow?

Xylem and phloem in plants carry out a function similar to veins and arteries in animals. In the circulatory system, blood flows through the arteries and veins from areas of high pressure to areas of low pressure. Plants also depend on bulk flow to transport materials to various places. Water in the leaves’ xylem evaporates in a process called transpiration, which creates less pressure in the xylem. The water can then flow up through the xylem into the zone of less pressure.\nIn general, bulk flow in plants is a quicker process than osmosis or diffusion, both of which involve a passive trans..

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