The evidence for aliens, weighed

Are aliens real?

Ancient aliens, UFOs and life in the cosmos: every claim checked against the evidence, with a verdict.

Did aliens visit ancient Earth?2/100 evidenceNo evidenceEvery famous "ancient alien" site has a human explanation, often with the builders' own tools and records.Plausible in principle? LowAre aliens visiting Earth now?6/100 evidenceUnprovenReal unexplained sightings exist, but unexplained is not alien. No craft, body or clean data has been shown.Plausible in principle? LowIs there intelligent life out there?12/100 evidenceNo detection yetBillions of habitable-zone planets and a few disputed hints of life, but no signal from anyone, so far.Plausible in principle? High

Latest developments

All updates
  1. The Pentagon's 7th UAP release: 28 files

    Includes a June 2026 memo about a silent black triangle at a sensitive western US site (no physical evidence found) and space-race guidance on handling crashed craft. Source: EarthSky

  2. Mars' best life candidate is stranded

    With Mars Sample Return cancelled, the Sapphire Canyon sample may never reach an Earth lab; China's Tianwen-3 plans its own sample return. Source: CNN

  3. 6th release: 71 files

    Pentagon research papers from 2008 to 2012 (including warp drives), a 1952 Project Blue Book recording and recent Middle East footage. Source: FOX 10 video

  4. 5th release: gunship footage

    An AC-130J recorded about 25 unidentified objects over the Gulf of Oman in 2021; also an orb over a Middle East town (January 2025). Source: war.gov/UFO

  5. Secrecy pledges no longer block UAP reports

    Intelligence guidance says non-disclosure agreements don't stop staff from reporting UAP information to AARO or the PURSUE task force. Source: DLA Piper

Open cases: what do you think?

All open cases

Six cases where the data is credible and the answer isn't settled. Weigh the competing explanations and cast your vote.

Worth watchingThe Nimitz "Tic Tac"November 2004 · Off San Diego, USANavy pilots and radar tracked a white craft that outflew their fighter jets.Worth watchingThe Yemen "orb" and the Hellfire missileFilmed Oct 2024, shown Sept 2025 · Off YemenA US drone's missile hit a glowing orb and appeared to bounce off.Worth watchingThe silent black triangleJune 2026 · Western USAFederal agents saw a matte black triangle hover and fly off silently.Worth watchingK2-18b and dimethyl sulfideApril 2025 · 124 light years awayThe James Webb telescope found a gas that on Earth only life makes.Worth watchingMars: the "leopard spots" of Cheyava FallsJuly 2024; paper September 2025 · Jezero Crater, MarsNASA's rover found the clearest sign of ancient life on Mars.Worth watchingEnceladus's ocean plumes2005 to 2023 · Saturn's moonSaturn's icy moon has everything life needs.

Explore the evidence

All verdicts
Aliens in the pastPyramids, Nazca, Puma Punku and 12 more, checked.UFOs and UAPRoswell to the 2026 Pentagon files.Life in the cosmosSETI, biosignatures and the Drake equation.Official files and videosGovernment reports, hearings and NASA briefings.Debunked or suspicious?All 44 claims on one board, sorted by verdict.Aliens in cultureFrom War of the Worlds to Men in Black.

The scoreboard

See every claim

We checked 44 of the most famous alien claims against the best evidence we could find.

8Debunked24Explained6Unproven6Worth watching0Confirmed alien
Debunked Shown to be false, a hoax or a misreading.Explained A solid ordinary explanation fits the evidence.Unproven Not explained, but no evidence it is alien either. Usually too little data.Worth watching Credible data, genuinely open. The cases that could move the meter.

Tripwires: what would change our minds

All tripwires

Play: Alien or not?

We show you a famous claim, you guess the verdict. Ten claims a round. Most people think more cases are unexplained than really are.

Start the quiz
The Fermi paradoxSo where is everybody? 14 answers, ranked by how seriously scientists take them.Alien self check-inVisiting Earth? Register your visit. Our experts will verify the information.

By the numbers

6,000+confirmed exoplanetsNASA Exoplanet Archive passed 6,000 in September 20251 in 5Sun-like stars may have an Earth-size planet in the habitable zoneEstimate from Kepler data (Petigura et al., 2013)66 yearsof SETI listeningSince Frank Drake's Project Ozma in 19600confirmed alien signalsEvery candidate so far was natural or human-made1,652UAP reports held by AARO by mid-2024AARO annual report, November 20247Pentagon UAP file releases in 2026PURSUE releases on war.gov/UFO, May to October 202612,618sightings in Project Blue Book701 stayed "unidentified" (1952 to 1969)0confirmed alien lifeformsThree biosignature candidates are still under debate

How we judge

Extraordinary claims need extraordinary evidence, and "we can't explain it" is not the same as "it's aliens". For each claim we look for the original source, the official record and the best expert analysis, then give one of four verdicts:

Debunked Shown to be false, a hoax or a misreading.Explained A solid ordinary explanation fits the evidence.Unproven Not explained, but no evidence it is alien either. Usually too little data.Worth watching Credible data, genuinely open. The cases that could move the meter.

We keep an open mind in both directions: the universe is huge, and some military sightings are genuinely unexplained. If a tripwire is ever hit, the meters move. More about us.