Transit of Venus

A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and a superior planet, becoming visible against (and hence obscuring a small portion of) the solar disk. During a transit, Venus can be seen from Earth as a small black disk moving across the face of the Sun. The duration of such transits is usually measured in hours (the transit of 2012 lasted 6 hours and 40 minutes). A transit is similar to a solar eclipse by the Moon. While the diameter of Venus is more than 3 times that of the Moon, Venus appears smaller, and travels more slowly across the face of the Sun, because it is much farther away from Earth.

Transits of Venus are among the rarest of predictable astronomical phenomena. They occur in a pattern that generally repeats every 243 years, with pairs of transits eight years apart separated by long gaps of 121.5 years and 105.5 years. The periodicity is a reflection of the fact that the orbital periods of Earth and Venus are close to 8:13 and 243:395 commensurabilities.

Venus

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. It is named after the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°.

Venus is a terrestrial planet and is sometimes called Earth's "sister planet" because of their similar size, mass, proximity to the Sun and bulk composition. It is radically different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. The atmospheric pressure at the planet's surface is 92 times that of Earth. With a mean surface temperature of 735 K (462 °C; 863 °F), Venus is by far the hottest planet in the Solar System, even though Mercury is closer to the Sun. Venus is shrouded by an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light. It may have had oceans in the past, but these would have vaporised as the temperature rose due to a runaway greenhouse effect. The water has most probably photodissociated, and, because of the lack of a planetary magnetic field, the free hydrogen has been swept into interplanetary space by the solar wind. Venus's surface is a dry desertscape interspersed with slab-like rocks and periodically resurfaced by volcanism.

Transit

Transit may refer to:

Computing

Science and engineering

Transportation

The Transit of Venus (Doctor Who audio)

The Transit of Venus is a Big Finish Productions audiobook based on the long-running British science fiction television series Doctor Who.

The Companion Chronicles "talking books" are each narrated by one of the Doctor's companions and feature a second, guest-star voice along with music and sound effects.

Plot

The year is 1770, and daring explorer Captain James Cook and his crew on the Endeavour are navigating the Pacific Ocean. Into their midst come strangers: the Doctor and Ian Chesterton, who are believed to have come from Venus. But the TARDIS is lost to them - along with both Susan and Barbara - and Ian makes an enemy of the ship's chief scientist, Joseph Banks.

Cast

External links

United States Marine Band

The United States Marine Band is the premier band of the United States Marine Corps. Established by act of Congress on July 11, 1798, it is the oldest of the United States military bands and the oldest professional musical organization in the United States. Today, the Marine Band also includes the Marine Chamber Orchestra and Marine Chamber Ensembles.

The Marine Band is entirely separate from its sister military band, the United States Marine Drum and Bugle Corps ("The Commandant's Own") and the 10 active duty Marine Corps field bands.

The Marine Band is uniquely known as "The President's Own" because of its historic connection to the President of the United States. The relationship between the Marine Band and the White House began on New Year's Day 1801, when President John Adams invited the band to perform at the Executive Mansion. Later that year, Thomas Jefferson initiated the tradition of Marine Band performances by requesting that it perform at his inauguration. The Marine Band has played at every United States presidential inauguration since.