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Known objects in the Kuiper belt
Known objects in the Kuiper belt

The Kuiper belt is a circumstellar disc in the Solar System extending beyond the orbit of Neptune, at 30 to 50 astronomical units from the Sun. It is similar to the asteroid belt between Mars and Jupiter, but far larger—20 times as wide and 20 to 200 times as massive. Like the asteroid belt, it consists mainly of small bodies that are remnants from the Solar System's formation. Many asteroids are composed primarily of rock and metal, but most Kuiper belt objects are composed largely of frozen volatiles such as methane, ammonia and water. The disc was named after Dutch-American astronomer Gerard Kuiper, though he did not predict its existence. Some of the Solar System's moons, such as Neptune's Triton and Saturn's Phoebe, are thought to have originated in the region. It is home to three officially recognized dwarf planets: Haumea, Makemake, and Pluto, the largest and most massive member of the Kuiper belt. Originally considered a planet, Pluto was reclassified as a dwarf planet in 2006. (Full article...)

Part of the Solar System series, one of Wikipedia's featured topics.

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Beatrice Alexander
Beatrice Alexander

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Emmanuel Macron in 2015
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May 12: Birth of Muhammad al-Mahdi (Shia Islam, 2017)

Coppergate Helmet
Coppergate Helmet

Lady Grange (d. 1745) · Katharine Hepburn (b. 1907) · Alexander Esenin-Volpin (b. 1924)

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The British Overseas Territory of Bermuda has a long history of encounters with Atlantic tropical cyclones, many of which inflicted significant damage and influenced the territory's development. A small archipelago comprising about 138 islands and islets, Bermuda occupies 21 square miles (54 km2) in the North Atlantic Ocean, roughly 650 miles (1,050 km) east of Cape Hatteras, North Carolina. The islands are situated far outside the main development region for Atlantic hurricanes, but within the typical belt of recurving tropical cyclones. According to the Bermuda Weather Service, the islands of Bermuda experience a damaging tropical cyclone once every six to seven years, on average. Due to the small area of the island chain, landfalls and direct hits are rare. Events have caused Bermuda widely varying degrees of damage. A hurricane in 1609 was responsible for the first permanent settlement on Bermuda: in late July, the Jamestown-bound, British ship Sea Venture nearly foundered in the storm and sought refuge on the islands, which the passengers found surprisingly hospitable. Hurricane Fabian was the most intense storm to impact the territory in modern times. (Full list...)

Today's featured picture

Cepheus

Cepheus is a constellation in the northern sky. Named after Cepheus, King of Aethiopia, in Greek mythology, it was listed by the 2nd century astronomer Ptolemy and remains one of the 88 modern constellations. Its brightest star is Alpha Cephei. The constellation also has the hyperluminous quasar S5 0014+81, which hosts the most massive black hole known in the universe.

This illustration was included in Urania's Mirror, a set of celestial cards illustrated by Sidney Hall.

Illustration: Sidney Hall; restoration: Adam Cuerden

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