First screen, captured 1 day ago. Open the video.

Dwarf planet candidate appears which takes roughly 280 years to orbit our sun

What HN thinks

A new rock turns up 280 years out, and the thread immediately relitigates Pluto's 2006 demotion.

Pluto demotion debate reignites
Some say the dwarf planet category was obviously right given Eris, Ceres and others. Others argue the IAU definition is arbitrary, reverse-engineered, or badly named, and that dwarf planets should be a subtype of planet.
Classification is mostly semantics
Several commenters see the argument as bikeshedding over labels and would rather talk about the objects themselves.
Rubin found it despite the Milky Way
The object was hidden against the dense galactic plane, and the new Vera Rubin survey is unusually good at spotting movers there. It is far too small to be Planet X or Planet Nine.

Consensus: There is no consensus on Pluto. Most agree the discovery shows Rubin's power and that this object is not the hypothetical Planet Nine.

Recommended in the comments

ketev ↗ (tool): A former orbit computer shared it to show ED138's orbit and the known asteroid population.
spacemap ↗ (tool): Offered as a similar orbit viewer that works better on mobile.
Celestia ↗ (tool): Suggested as a place for an add-on modelling ED138.

Summarised by Claude from the comment thread 17 hours ago.

Points: 381
Comments: 169
Best rank: #3
Posted: 2026-11-12 by cybermango
Category: Space

dwarf-planets vera-rubin-observatory kuiper-belt astronomy solar-system 2026-ed138

All captures:

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Captured 1 day ago. Click for the whole screenshot.

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