Discovery
Percival Lowell, an astronomer in 1905, puzzled over the questionable existence of some unknown object, whose force of gravity was affecting both Neptune and Uranus’ orbits. Ten years later, Lowell predicted the new planet’s location and used a telescope to photograph the area of the sky based on his prediction. However, Lowell died without ever finding this new planet.
Later, Clyde W. Tombaugh used Lowell’s predictions with an even more powerful telescope to photograph the sky. In 1930, an image of the new planet appeared on three photographs taken by Tombaugh. Pluto is named for the Roman god of the dead and also contains the initials of Percival Lowell as its first two letters.
Planet Description
There is little information on Pluto because it is so far from the Earth. Some believe Pluto is composed of frozen methane gas while others suggest a mixture of nitrogen, methane, ethane, and carbon monoxide ices. The atmosphere is probably composed of methane gas and nitrogen. Since astronomers cannot accurately determine the size of Pluto, a best estimate on the diameter is about 1,400 miles, which is less than a fifth of the Earth. Astronomers also believe Pluto is mostly brown in color and has an icy environment. The estimated temperature may be about -378 to -396 degrees F (-228 to -238 degrees C). Furthermore, there is little belief that Pluto has any life forms.
Mission to Pluto
In January 2006 NASA launched the New Horizons probe, which is expected to fly by Pluto in 2015. Its mission objectives are:
- Map surface composition of Pluto and Charon
- Map surface temperatures on Pluto and Charon
- Characterize geology and the look of Pluto and Charon
- Characterize the neutral atmosphere of Pluto and its escape rate
- Search for rings and additional satellites around Pluto
- Search for an atmosphere around Charon
- Conduct similar investigations of one or more Kuiper Belt Objects
General Informational Resources
I.) The National Space Science Data Center (NSSDC), "Welcome to the NSSDC." NASA. http://nssdc.gsfc.nasa.gov/ (accessed 27.November, 2006).
NASA’s archive for space science mission data resides here. A vast resource for space, solar, and planetary astrophysics data as well as mission information.
II.) NASA’s Solar System Exploration, "Solar System Exploration Home Page." NASA. http://solarsystem.jpl.nasa.gov/index.cfm (accessed 27. November, 2006).
The exploration website offers information about the planets in our Solar System, news and events both in NASA and in the sky, missions, science and technology issues for both kids and adults.
III.) Spinrad, Hyron. "Pluto." World Book Online Reference Center. 2004. World Book, Inc. http://www.worldbookonline.com/wb/Article?id=ar435500 or http://www.nasa.gov/worldbook/pluto_worldbook.html (accessed 27.November, 2006).
This is a general educational article on the history and present information regarding Pluto.
IV.) Hubble Space Telescope, "Hubble Site -- Out of the ordinary... out of this world." Space Telescope Science Institute's Office of Public Outreach. http://hubblesite.org/ (accessed 27. November, 2006).
Hubble Space Telescope website is currently being renovated. However, it is still operational despite their changes. The website is devoted to the Hubble discoveries, which holds pictures, information about the telescope, and educational resources for both kids and adults.
V.) Lowell Observatory, "Lowell Observatory." http://www.lowell.edu/index.html (accessed 3. December, 2006).
This is the Lowell Observatory website, which has research, educational information about astronomy, and the Discovery Channel Telescope.
Pluto's size comparison picture is the property of the New Horizon's Website.