Pluto a Planet? New Research from UCF Suggests Yes
The reason Pluto lost its planet status is not valid, according to new research from the University of Central Florida in Orlando. In 2006, the International Astronomical Union, a global group of astronomy experts, established a definition of a planet that required it to "clear" its orbit, or in other words, be the largest gravitational force in its orbit. [...] [Philip] Metzger, who is lead author on the study, reviewed scientific literature from the past 200 years and found only one publication -- from 1802 -- that used the clearing-orbit requirement to classify planets, and it was based on since-disproven reasoning.
[...] The planetary scientist said that the literature review showed that the real division between planets and other celestial bodies, such as asteroids, occurred in the early 1950s when Gerard Kuiper published a paper that made the distinction based on how they were formed. However, even this reason is no longer considered a factor that determines if a celestial body is a planet, Metzger said.
[...] Instead, Metzger recommends classifying a planet based on if it is large enough that its gravity allows it to become spherical in shape. "And that's not just an arbitrary definition, Metzger said. "It turns out this is an important milestone in the evolution of a planetary body, because apparently when it happens, it initiates active geology in the body." Pluto, for instance, has an underground ocean, a multilayer atmosphere, organic compounds, evidence of ancient lakes and multiple moons, he said. "It's more dynamic and alive than Mars," Metzger said. "The only planet that has more complex geology is the Earth."
Planet Ceres, please.
The Reclassification of Asteroids from Planets to Non-Planets (DOI: 10.1016/j.icarus.2018.08.026) (DX)
Related: Pluto May Regain Status as Planet
Earth is a "Dwarf Planet" Because it has not Cleared its Orbit
(Score: 0) by Anonymous Coward on Saturday September 08 2018, @09:13AM (7 children)
it's a gaseous giant. Same with Saturn, except Saturn is a ringed gaseous giant.
Now every former planet can be a unique snowflake. Let the labeling commence.
Uranus and Neptune are Ice Giants
Mercury is an inferior planet
Venus and Earth are terrestrial planets.
Pluto's a dwarf planet
In fact, iun reality, there are no planets, just naming labels.
Mars? OK...well, Mars is stupid. Let's call it a red planet.
(Score: 0) by Anonymous Coward on Saturday September 08 2018, @09:42AM (3 children)
The gaseous giants and Ice giants have real planets at their cores. They are just normal planets with really thick atmospheres.
(Score: 1, Insightful) by Anonymous Coward on Saturday September 08 2018, @12:09PM (2 children)
How do you know they are real? Jupiter is pretty complex, it may have an imaginary core.
(Score: 2) by RS3 on Saturday September 08 2018, @01:08PM (1 child)
√(−1) ?
(Score: 2) by Immerman on Saturday September 08 2018, @02:41PM
Good thing it's round then. It it were square it would go negative. (a black hole?)
(Score: 1, Insightful) by Anonymous Coward on Saturday September 08 2018, @09:50AM
Asteroid belt is a type of planet too: former planet
(Score: 1) by fritsd on Saturday September 08 2018, @02:02PM
I once watched part of "Der Ring" on TV (Siegfried I think it was) but fell asleep after 5 hours.
Which planets are Brünhild and Alberich and Fafner, again??
(Score: 2) by theluggage on Saturday September 08 2018, @08:34PM
You clearly haven't asked Pluto whether it considers itself to be a planet, you insensitive clod!