Trans-Neptunian object

A trans-Neptunian object (TNO, also written transneptunian object) is any minor planet in the Solar System that orbits the Sun at a greater average distance (semi-major axis) than Neptune, 30 astronomical units (AU). Twelve minor planets with a semi-major axis greater than 150 AU and perihelion greater than 30 AU are known, which are called extreme trans-Neptunian objects (ETNOs).

The first trans-Neptunian object to be discovered was Pluto in 1930. It took until 1992 to discover a second trans-Neptunian object orbiting the Sun directly, (15760) 1992 QB1. As of January 2016 over 1,750 trans-Neptunian objects appear on the Minor Planet Center's List Of Transneptunian Objects. Of these TNOs, 1,563 have a perihelion further out than Neptune (30.1 AU).As of November 2009, two hundred of these have their orbits well-enough determined that they have been given a permanent minor planet designation.

The largest known trans-Neptunian object is Pluto, followed by Eris, Makemake, 2007 OR₁₀ and Haumea. The Kuiper belt, scattered disk, and Oort cloud are three conventional divisions of this volume of space, though treatments vary and a few objects such as Sedna do not fit easily into any division.

New Horizons

New Horizons is an interplanetary space probe that was launched as a part of NASA's New Frontiers program. Engineered by the Johns Hopkins University Applied Physics Laboratory (APL) and the Southwest Research Institute (SwRI), with a team led by S. Alan Stern, the spacecraft was launched with the primary mission to perform a flyby study of the Pluto system, and a secondary mission to fly by and study one or more other Kuiper belt objects (KBOs).

On January 19, 2006, New Horizons was launched from Cape Canaveral Air Force Station directly into an Earth-and-solar escape trajectory with a speed of about 16.26 kilometers per second (58,536 km/h; 36,373 mph). After a brief encounter with asteroid 132524 APL, New Horizons proceeded to Jupiter, making its closest approach on February 28, 2007, at a distance of 2.3 million kilometers (1.4 million miles). The Jupiter flyby provided a gravity assist that increased New Horizons' speed; the flyby also enabled a general test of New Horizons' scientific capabilities, returning data about the planet's atmosphere, moons, and magnetosphere.

Kuiper belt

The Kuiper belt /ˈkaɪpər/ or /'køypǝr/ (as in Dutch), sometimes called the Edgeworth–Kuiper belt, is a circumstellar disc in the Solar System beyond the planets, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun. It is similar to the asteroid belt, but it is far larger—20 times as wide and 20 to 200 times as massive. Like the asteroid belt, it consists mainly of small bodies, or remnants from the Solar System's formation. Although many asteroids are composed primarily of rock and metal, most Kuiper belt objects are composed largely of frozen volatiles (termed "ices"), such as methane, ammonia and water. The Kuiper belt is home to three officially recognized dwarf planets: Pluto, Haumea, and Makemake. Some of the Solar System's moons, such as Neptune's Triton and Saturn's Phoebe, are also thought to have originated in the region.

The Kuiper belt was named after Dutch-American astronomer Gerard Kuiper, though he did not actually predict its existence. In 1992, 1992 QB₁ was discovered, the first Kuiper belt object (KBO) since Pluto. Since its discovery, the number of known KBOs has increased to over a thousand, and more than 100,000 KBOs over 100 km (62 mi) in diameter are thought to exist. The Kuiper belt was initially thought to be the main repository for periodic comets, those with orbits lasting less than 200 years. However, studies since the mid-1990s have shown that the belt is dynamically stable, and that comets' true place of origin is the scattered disc, a dynamically active zone created by the outward motion of Neptune 4.5 billion years ago; scattered disc objects such as Eris have extremely eccentric orbits that take them as far as 100 AU from the Sun.

Dwarf planet

A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite. That is, it is in direct orbit of the Sun, and is massive enough for its gravity to crush itself into a hydrostatic equilibrium shape (usually a spheroid), but has not cleared the neighborhood of other material around its orbit.

The term dwarf planet was adopted in 2006 as part of a three-way categorization of bodies orbiting the Sun, brought about by an increase in discoveries of objects farther away from the Sun than Neptune that rivaled Pluto in size, and finally precipitated by the discovery of an even more massive object, Eris. The exclusion of dwarf planets from the roster of planets by the IAU has been both praised and criticized; it was said to be the "right decision" by astronomer Mike Brown, who discovered Eris and other new dwarf planets, but has been rejected by Alan Stern, who had coined the term dwarf planet in 1990.

The International Astronomical Union (IAU) currently recognizes five dwarf planets: Ceres, Pluto, Haumea, Makemake, and Eris. Brown criticizes this official recognition: "A reasonable person might think that this means that there are five known objects in the solar system which fit the IAU definition of dwarf planet, but this reasonable person would be nowhere close to correct."

Kay Hanley

Kathleen Marie "Kay" Hanley (born September 11, 1968) is an American musician. She is best known as the vocalist for the alternative rock band Letters to Cleo.

Life and career

Hanley was born in the Dorchester neighborhood of Boston, Massachusetts. She grew up diagonally across the street from Donnie and Mark Wahlberg. She was a member of Letters To Cleo from 1990 to 2000 (the length of the band's existence, with the exception of the 2008-2009 reunion tour). The band name was conceived by Hanley in reference to a pen pal named Cleo that she had when she was younger. In 1997, she began working on other projects, beginning with a role in the Boston Rock Opera's performance of Jesus Christ Superstar as Mary Magdalene.

In 1999, Hanley made a cameo as herself in the film 10 Things I Hate About You, singing a cover version of Nick Lowe's "Cruel to Be Kind" at the movie characters' high school prom, in addition to performing "Come On" with Letters to Cleo during an earlier scene at a club. Towards the end of Letters to Cleo's career, she began performing with her husband and fellow Letters To Cleo member Michael Eisenstein outside of the band. Around the same time, she gave birth to their daughter, Zoe.