BLC1 from Proxima Centauri

The claim

"A narrow radio signal seemed to come from our nearest star."

Where the idea comes from

Breakthrough Listen data from April and May 2019 showed a narrowband signal at 982 MHz while the telescope pointed at Proxima Centauri.

What the evidence shows

1. The signal passed the first checks: it appeared when pointing at the star and disappeared when pointing away.
2. Its frequency drifted in a way that did not match what Proxima's planets' motion would cause.
3. Two papers in Nature Astronomy (2021) found dozens of "look-alike" signals related to the frequencies of common electronics, and concluded BLC1 was human-made interference.

What is still open

Nothing material; the analysis is a model for how a real candidate would be tested.

Our verdict

Explained Human radio interference.

Sources

• Breakthrough Listen
• BLC1 (Wikipedia)

Checked 31 October 2026. Spotted a newer source? Tell us.