Canned Blog: Hvorfor Pluto ble reklassifisert som dvergplanet

mandag 14. september 2009

Hvorfor Pluto ble reklassifisert som dvergplanet

Mange har lurt på hvorfor Pluto ikke lenger er definert som en planet. Jeg fant nylig ut hva som klassifiserer et objekt som planet. Følgende tre kriterier må oppfylles:

Banen må gå rundt sola, ikke rundt et annet solsystemobjekt. Dette gjør at f.eks. Månen, eller Titan (som er enorm) ikke defineres som planeter. Pluto gjør dette.
Det må ha nok gravitasjonskraft til å forme seg selv til en sfærisk form. Pluto: OK
Det må rydde nabolaget i omløpsbanen sin. Her stryker Pluto

For mer informasjon, se Universe Today: Why is Pluto Not a Planet.

Det er også et par lenker til noen veldig interessante podcaster der. I episode 1 diskuteres IAUs avgjørelse, og i episode 2 Pluto og det isete ytre solsystemet.

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Elvis Aron Presley: Did You Know?

In Wright City, Missouri (about 40 miles west of St. Louis) there is a roadside attraction called the "Elvis Is Alive Museum.". Their theory is that Elvis faked his own death and has lived in obscurity ever since. They're serious. (www.artistfacts.com)
Elvis' televised concert Aloha From Hawaii was the first global satellite broadcast devoted to a single entertainer. It was seen by 51% of US viewers, more households than watched the first moon landing. In many countries it captured 70-90+% of the television audience. Ultimately, nearly 1.5 billion people in 40 countries saw this performance. (www.artistfacts.com)
In 1955, Sam Phillips sold Elvis' contract to RCA records for $35,000. According to music journalist Robert Fontenot, this was not as big a blunder as it sounds, as the music business in 1955 was a quick-cash game; no label owner, certainly not a small, regional one like Phillips, could have possibly asked for a percentage of an artists' future royalties once he was signed away. $35,000 was by far the largest amount ever paid for any artist by a major label, and no one in the business considered Rock music more than a passing fad; if anything, RCA was thought to have wildly overpaid for Elvis. Phillips proved he was indeed a shrewd businessman by investing that $35,000 in a small upstart hotel chain in Memphis. The name of that chain was the Holiday Hotel; you may know it better as the Holiday Inn. (www.artistfacts.com)
In 1959 Elvis became the first artist to release an album without an artist name on the cover, front or back, with the album For LP Fans Only. (www.artistfacts.com)
Elvis is the only artist inducted into the Rock and Roll Hall of Fame, the Country Hall of Fame, and the Gospel Hall of Fame. (www.artistfacts.com)