64 forecasters

Will Planet Nine be Discovered by mid-2021?

4%chance

4%chance

ResolvedNo

ResolvedNo

The community gave this a 4% chance, and it resolved No.

Forecast Timeline

Authors:

Opened:

Jul 5, 2020

Closes:

Jan 2, 2021

Resolved:

Jul 1, 2021

Spot Scoring Time:

Jul 7, 2020

Natural Sciences

2020-2021 Leaderboard

Meet ‘Planet Y’ As New Evidence Suggests Secret World Beyond Neptune

Forbes•Sep 11, 2025

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