Questions tagged [9th-planet]

Questions relating to the discovery of a new ninth planet (not Pluto) hypothesized in the Solar System.

5 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
5 votes
0 answers
78 views

What about the U planet?

In 2014 and 15, an object called U has been detected by the ALMA in Chile, considered likely to be a super-Earth at 300 AU, among other options. Is it located where the hypothetical super-Earth ...
  • 1,538
5 votes
0 answers
134 views

Would the existence of Planet Nine rule out the possibility of a sixth giant planet?

I'm aware that there have been attempts to simulate the evolution of the Solar System with six giant planets1, as opposed to the traditional four or five. The recent proposed Planet Nine would ...
  • 34.5k
2 votes
0 answers
57 views

Based on discoveries of new TNOs since 2016, is planet Nine still necessary to explain the TNO's orbits?

It is almost five years since the announcement of the likelyhood of another planet that is responsible for clustering eTNO's orbits, very close perihelia of detached dwarf planets to the Sun, and high ...
  • 357
2 votes
0 answers
84 views

How much heat emanates from the planets after formation?

The 2nd answer to this question by MBR got me thinking about this. Is there some general guideline for residual heat a planet should emit, say 4.5 billion years after formation. I'm defining heat ...
  • 23.1k
0 votes
0 answers
68 views

If the hypothetical planet had a perihelion around 60 AU, would some consider it being responsible for the Kuiper cliff?

If Planet X had a perihelion around 60 AU and an aphelion in the vicinity of Sedna's aphelion (940 AU), would it be considered to be responsible for both the high eccentricities of TNO's orbits and ...
  • 1,538