Unidentified is the beginning of a question.

A sighting can be worth investigating without its origin being known.

Illustrative notebook and observing equipment — AI-generated artist’s impression · illustrative, not evidence of an event.

UFO and UAP

UFO stands for unidentified flying object. UAP is now commonly used for unidentified anomalous phenomena, a broader term. Neither label identifies an observation as an alien spacecraft.

What does the evidence establish?

NASA’s UAP FAQ states that it has not found credible evidence of extraterrestrial life and that there is no evidence that UAP are extraterrestrial. It also explains why limited data can prevent an observation from being verified or explained.

“We cannot identify this” and “we have identified an alien craft” are different claims.

A useful way to read a sighting report

1. What was recorded?

Separate original photographs, measurements and notes from later retellings. Record what is missing as carefully as what is available.

2. What could be checked?

Look for a time, place, viewing direction and duration. Ask whether independent observations or records could help test an explanation.

3. Which explanations fit?

Compare explanations with the actual record. An interesting possibility still needs evidence that distinguishes it from alternatives.

4. What remains unknown?

State the limits plainly. Missing information may leave a question open without supporting a particular answer.

Try a practical example

A line of lights in the sky: could it be Starlink?

Read the source

NASA: UAP frequently asked questions

Source reviewed 4 November 2026.