Will the US confirm that aliens exist before 2027?
Crossbook compares what two exchanges, Polymarket and Kalshi, charge for the same event, and publishes a permanent scored record of its own forecasts under published rules.
Both venues are priced below, side by side.
Informational only. Not trading or investment advice. Prices may be delayed or inaccurate, and a difference between venues can be an artifact — how this is measured.
How each venue defines this
Each exchange's own settlement text, quoted as written. Where they differ, the difference is usually why the prices do.
Settles Jan 1, 27
This market will resolve to "Yes" if the President of the United States, any member of the Cabinet of the United States, any member of the Joint Chiefs of Staff, or any US federal agency definitively states that extraterrestrial life or technology exists by December 31, 2026, 11:59 PM ET. Otherwise, this market will resolve to "No". The primary resolution source for this market will be official information from the government of the United States, however a consensus of credible reporting will also be used.
Settles Jan 1, 27
If the President, any member of the Cabinet, any member of the Joint Chiefs of Staff, or any US federal agency definitively states that extraterrestrial life or technology exists before Jan 1, 2027, then the market resolves to Yes.
Settlement basis
A person confirmed these two markets ask the same question. Their settlement documents have not been compared, so treat the price difference as unverified rather than as a like for like gap.
Confirmed as the same question: Will the US confirm that aliens exist before 2027?
Crossbook forecast
No public Crossbook forecast on this market yet. Every call that is made is timestamped and scored on the public record, win or lose.
Context
Kalshi prices this at 5% while Polymarket has it at 4%, a gap of 1.2 points on the same question. Whether that gap is real depends entirely on whether the two settle on the same terms.
Volume over the last 24 hours is active, at about $77,549 on the busier venue.
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Crossbook publishes every forecast it makes, timestamped before the answer is known and scored against the market afterwards. See the public record and the rules it is held to.