Featured Research

from universities, journals, and other organizations

Pluto Safe From Demotion

Date:
February 2, 1999
Source:
University Of Kansas
Summary:
The short national nightmare is coming to an end. The solar system will continue to have nine planets. "There is no plan to 'downgrade' or 'demote' Pluto," says Brian Marsden, head of the International Astronomical Union's Minor Planet Center. "It will stay as a planet."

LAWRENCE, Kan. -- The short national nightmare is coming to an end. The solar system will continue to have nine planets.

"There is no plan to 'downgrade' or 'demote' Pluto," says Brian Marsden, head of the International Astronomical Union's Minor Planet Center. "It will stay as a planet."

Sometime early this year, it's likely Pluto will be designated a "transneptunian object" -- but not lose its planetary status, as has lately been rumored.

The designation, new for Pluto, already describes a group of 90 known bodies on the outer fringes of the solar system.

"This is like giving it a social security number," Marsden said. "Humans acquire names soon after birth. Later they get social security numbers. Does having the latter demote them in some way? Of course not."

Controversy has swirled around the pint-sized planet for various reasons, including its smallness and eccentric orbit. But the possibility of its being demoted touched nerves.

Among the miffed was Patricia Fort Johnson, a former resident of Streator, Ill. Pluto's discoverer, Clyde Tombaugh, was born near there.

Tombaugh attended high school in Burdett, Kan., and went to school at the University of Kansas, in Lawrence, so the possible demotion rankled folks in those towns, too. At KU, an observatory is named after Tombaugh.

Johnson recently wrote to Steve Shawl, KU professor of physics and astronomy, about her distress.

"I would be sorely disappointed," she told Shawl, "if Pluto were to be demoted from planet status. Where would be our truth?"

It was Shawl who put her in contact with Marsden, who responded with assurance and the social security analogy.

All this amounts to quite a bit of fuss over an odd little ball. Pluto is only about 1,450 miles across, about the distance between Kansas City and Las Vegas. It's considerably smaller than Earth's moon, which is about 2,150 miles across.

That's only one reason some people don't consider it a planet. Another is that it breaks a trend in the solar system, says Bruce A. Twarog, KU professor of physics and astronomy. While the inner planets, out to Mars, are basically orbiting rocks, the outer ones are gigantic gas balls -- until you get to Pluto, says Twarog.

If you drilled from the surface of Pluto toward its center, you'd be boring through ice the first quarter of the way. It's nothing you'd want to put into a margarita though, being frozen nitrogen, carbon monoxide and methane.

Currently, Shawl says, Pluto has a thin atmosphere. That's only because it's as close to the sun as it ever gets, and the heat is changing some of the ice into gas.

Pluto orbits the sun every 248 years, moving, unlike other planets, in a big ellipse rather than a circle.

For about 20 of those 248 years, it's closer to the sun than Neptune, which is ordinarily the eighth planet out from the sun, Shawl says. In fact, Pluto has been the eighth planet since Jan. 21 ,1979, but becomes the ninth planet again on Feb. 11 of this year -- and the pro-Pluto crowd can breathe a sigh of relief that it will still be a planet on that date.

Despite Pluto's eccentricities, the debate about whether it's a planet is "much ado about nothing," Shawl says.

David Tholen, a KU graduate now at the University of Hawaii, adds, "Debating the dividing line between planet and minor planet, or asteroid, is like debating the dividing line between city and town, river and stream."

"It's nothing that should send anybody out of orbit," Shawl says.


Story Source:

The above story is based on materials provided by University Of Kansas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Kansas. "Pluto Safe From Demotion." ScienceDaily. ScienceDaily, 2 February 1999. <www.sciencedaily.com/releases/1999/02/990202072542.htm>.
University Of Kansas. (1999, February 2). Pluto Safe From Demotion. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/1999/02/990202072542.htm
University Of Kansas. "Pluto Safe From Demotion." ScienceDaily. www.sciencedaily.com/releases/1999/02/990202072542.htm (accessed July 29, 2014).

Share This




More Space & Time News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com
NASA EDGE: OCO-2 Launch

NASA EDGE: OCO-2 Launch

NASA (July 25, 2014) NASA EDGE webcasts live from Vandenberg AFB for the launch of the Oribiting Carbon Observatory-2 (OCO) launch. Video provided by NASA
Powered by NewsLook.com
This Week @ NASA, July 25, 2014

This Week @ NASA, July 25, 2014

NASA (July 25, 2014) Apollo 11 celebration, Next Giant Leap anticipation, ISS astronauts appear in the House and more... Video provided by NASA
Powered by NewsLook.com
Space to Ground: Coming and Going

Space to Ground: Coming and Going

NASA (July 25, 2014) One station cargo ship leaves, another arrives, aquatic research and commercial spinoffs. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins