Blog Archive

An Auspicious Week for Astronomy

Posted by Mark Adler on 2009/05/11 11:54 CDT | 1 comments

On Monday, if all goes well, we will launch the Space Shuttle to rejuvenate one the greatest scientific missions launched on or off the Earth: the Hubble Space Telescope.

Pluto: The Discovery of a Planet

Posted by Amir Alexander on 2005/02/18 11:00 CST

To mark the 75th anniversary of the discovery of the planet Pluto, The Planetary Society presents to its readers the remarkable story of the discovery.

The Discovery of a Planet, Part 6: From Pluto to Sedna

Posted by Amir Alexander on 2005/02/17 11:00 CST

74 years after Clyde Tombaugh discovered Pluto as a faint dot on a pair of photographic plates, a modern group of astronomers made another remarkable discovery. On March 15, 2004, Michael Brown of Caltech, Chad Trujillo of the Gemini Observatory, and David Rabinowitz of Yale announced the discovery of Sedna – the furthest object ever detected in the Solar System.

The Discovery of a Planet, Part 5: The Aftermath

Posted by Amir Alexander on 2005/02/16 11:00 CST

The discovery of Planet X was announced to the world on March 13, 1930, which marked the anniversary of William Herschel’s discovery of Uranus in 1781 as well as Percival Lowell’s birthday. The observatory’s communiqué emphasized that the discovery was no coincidence, but the vindication of Lowell’s predictions made years before.

The Discovery of a Planet, Part 4: Clyde's Search

Posted by Amir Alexander on 2005/02/15 11:00 CST

Since his teenage years Clyde Tombaugh had been an avid amateur astronomer and a gifted telescope builder. Based on instructions contained in an article from a boy’s Sunday school paper, he built a series of telescopes of increasing power and quality on the family farm.

The Discovery of a Planet, Part 3: Planet X

Posted by Amir Alexander on 2005/02/14 11:00 CST

The discovery of Neptune accounted for nearly all the unexplained motions of the outer planets of the Solar System. Nevertheless, several astronomers insisted that some unexplained residual motions remained, pointing to the presence of a ninth planet beyond the orbit of Neptune.