Strange Laser-Like Pulses from a Sun-Like Star: A New Optical SETI Discovery

A multi-year optical SETI (Search for Extraterrestrial Intelligence) campaign has detected unexplained pairs of fast, identical light pulses from the Sun-like star HD 89389, located around 100 light-years away in the constellation Ursa Major. This finding, recently published in Acta Astronautica, has sparked renewed intrigue in the search for extraterrestrial technosignatures universetoday.com+4ui.adsabs.harvard.edu+4earthsky.org+4.

What the Study Found

• Survey scope: Over 1,300 sun-like stars were observed using a custom-designed 76 cm telescope and multichannel photometer earthsky.org.
• First detection: On May 14, 2023, two near-identical optical pulses were detected from HD 89389—each about 0.2 seconds long and separated by exactly 4.4 seconds. The fine structure of the first pulse repeats almost exactly in the second earthsky.org+3ui.adsabs.harvard.edu+3reddit.com+3.
• Rarity and repetition: No similar single pulses were found across more than 1,500 hours of observing. A similar pair was retrospectively identified in 2019 from star HD 217014 (51 Pegasi) but had been dismissed at the time as a false positive (e.g., a bird) thesun.co.uk+3ui.adsabs.harvard.edu+3reddit.com+3.

Why This Is Unusual

• The pulses are unlike anything recorded from natural or human-made sources like pulsars, satellites, meteorites, atmospheric turbulence, or interference space.com+4ui.adsabs.harvard.edu+4thesun.co.uk+4.
• These are repeated, structured optical bursts—something not previously observed in stars like HD 89389 en.wikipedia.org+4earthsky.org+4thesun.co.uk+4.
• The integrity of the instrument and thorough data analysis rule out technical glitches or false signals reddit.com.

Possible Explanations

Several hypotheses are on the table:

1. Edge diffraction or occultation: Some models suggest a compact object passing near the star could diffract starlight, creating matched pulse pairs space.comthesun.co.uk+2ui.adsabs.harvard.edu+2earthsky.org+2.
2. Unknown natural phenomenon: A novel astrophysical process affecting starlight remains possible—but highly speculative.
3. Technosignature: The signal’s structure and consistency place it among the strongest candidates for artificial origins—potentially from directed-energy (laser) broadcasts from an advanced civilization reddit.com+4earthsky.org+4ui.adsabs.harvard.edu+4.

From Universe Today to SETI Eyes

Universe Today describes the pulses as “fast identical pulses… something completely different from any known natural phenomenon” and notes the renewed focus on future observations . Another article titled “Not Saying It’s Aliens…” also emphasizes the candid but cautious tone of the research universetoday.com+5universetoday.com+5renfrewshireastro.co.uk+5.

SEO Boost: Why This Matters

• High search volume: Terms like “optical SETI”, “HD 89389 laser pulses”, and “technosignatures” are trending in astronomy communities.
• Timeliness: With the peer-reviewed paper published April 30, 2025, and multiple reputable outlets covering it in May and June 2025, the topic is fresh and newsworthy.
• Public intrigue: While no definitive extraterrestrial claim is made, the structured, unexplainable light signal stokes the imagination—and drives clicks.

What Comes Next?

• Follow-up observations are planned using arrays of optical telescopes aimed at HD 89389 and other candidates to track recurring pulses and triangulate source properties thesun.co.uk+3ui.adsabs.harvard.edu+3earthsky.org+3.
• Diffraction testing: If edge-occultation is valid, teams may employ telescope networks to detect movement and infer position, size, and velocity .
• Technosignature candidates: Astronomers will incorporate HD 89389 into LaserSETI and similar global optical arrays for continuous monitoring en.wikipedia.org+2en.wikipedia.org+2earthsky.org+2.

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Bottom Line

This recent optical SETI discovery—two identical, precisely spaced light pulses from HD 89389—is unlike any natural or instrumental artifact. It warrants intensive follow-up and attention from both SETI researchers and journalists. Whether it represents a new cosmic phenomenon or the first whisper of alien technology, the world is watching.