Who Needs Pluto Anyway?

[Smellincoffee]

http://www.space.com/10863-mystery-planet-tyche-debate.html

Space.com finally has an article on it.

Matthew Holman, a planetary scientist at the Harvard Smithsonian Institute of Astrophysics, is not a Tyche believer.

Though he hasn't read the latest version of Matese's and Whitmire's argument, Holman told Life's Little Mysteries, "Based on past papers that I've seen looking at where long-period comets came from in the sky, and finding signatures of large perturbers of the Oort cloud, I was not persuaded by the evidence."

Hal Levison, a planetary scientist at the Southwest Research Institute in Boulder, Colo., who recently authored a paper on the Oort cloud for Science Magazine, seconded that opinion.

"I haven't read this version of his paper, which he claims now has better statistics than the previous attempts, where he also claimed that he saw evidence of this object," Levison said. "But in previous papers, I really think he did his statistics wrong. Incredible claims require incredible proof and I really believe that he doesn't understand how to do this statistical analysis correctly."

"What Matese claims is that he sees an excess of comets coming from a particular place, which he attributes to the gravitational effects of a large planet in the Oort cloud. I have nothing against the idea, but I think the signal that he claims he sees is very subtle, and I'm not sure it's statistically significant," Levison told Life's Little Mysteries.

 

[Deego3]

All planets are baryonic. Perhaps a stranger name could be used.

 

[Mr. Dictator]

All planets are baryonic. Perhaps a stranger name could be used.

Byronic Planet?

 

[Berzerker]

there aint no Oort Cloud, it was a theory to explain long term comets we see entering the inner solar system

 

[Darth Caesar]

Sounds cool, another planet to conquer!

 

[Miles Teg]

there aint no Oort Cloud, it was a theory to explain long term comets we see entering the inner solar system

Is a theory. It's pretty strongly supported, which is why the assumption of an Oort cloud underlies a lot of modern astronomy.

 

[Berzerker]

I know its a theory, I said "it was a theory to explain long term comets" and thats true. But supported by what? And how is a lot of modern astronomy based on it?

 

[Braindead]

The Oort cloud is theoretical. One object has been found in the volume of space which the Oort Cloud would occupy. Here is an extract from the NASA website.

http://solarsystem.nasa.gov/scitech/display.cfm?ST_iD=105

Sedna is the only object known in the inner Oort cloud, but we suspect that there will be many more found

What is the Oort cloud and what is its relationship to Sedna?
The Oort cloud is a hypothetical shell of icy proto-comets in very loose orbits around the Sun that extends to a distance of almost halfway to the nearest star. Occasionally, passing stars cause a slight change in the orbit of one of these proto-comets which causes them to come streaking in to the inner solar system where we see them as comets.Though the Oort cloud has never been seen directly, the comets that we do see are very strong evidence of its existence. The Oort cloud is expected to be much further out than the orbit of Sedna. So why do we think Sedna is a member of the Oort cloud? We believe that the existence of Sedna is evidence that the Oort cloud actually extends much further in towards the Sun than previously thought. This "inner Oort cloud" was formed in the same manner as the previously known "outer Oort cloud." Early in the history of the solar system many small icy bodies were orbiting the Sun and getting sling-shot out by close encounters with planets. As they were travelling further and further from the Sun, the orbits of these bodies were affected by distant stars, causing them to slow down and stay attached to the Sun. Sedna probably suffered a similar fate, except the stars which affected it must have been much closer than previously expected. We believe that this is evidence that the Sun formed in a tight-knit group along with many other stars.

 

[Berzerker]

isn't there (or shouldn't there be) some statistical "chance" of star occultations from all those Oort Cloud comets? Shouldn't we be seeing stars dim slightly every few seconds, minutes, or hours? Or do the distances and small sizes of these comets make the dimming so negligible we cant tell when an Oort Cloud comet passed between us and a star? And then there should also be Oort Clouds around the stars we're looking at, and all the stars in the way or near the path of other stars...

I just dont buy into it... Long terms comets were sent on their long distance orbits thru interactions with other planets in our solar system, and there aint that many - not the millions or billions supposedly in this hypothetical cloud. Comets have their origins in the inner solar system.