Aliens Likely Exist — But They’re Choosing Silence, Scientist Says

Dec 12•2 min read

Why Aliens Are Staying SilentJohn Lund - Getty Images

Popular Mechanics highlights astrophysicist Robin Corbet’s argument that the lack of contact with aliens likely reflects either deliberate silence or physical limits on interstellar signaling, not absence of life. Editors John Gilpatrick and Jamie Sorcher review two leading ideas: the vastness of space makes contact unlikely, and advanced civilizations might intentionally avoid broadcasting their presence. Corbet’s paper stresses that even powerful transmissions weaken across light-years, so signals can become undetectable. The piece reframes the mystery as a technical and behavioral challenge for SETI efforts.

If extraterrestrial life exists, why haven't we heard from it? A new Popular Mechanics feature explores this question and highlights a recent paper by astrophysicist Robin Corbet that argues silence doesn't equal absence.

Editors John Gilpatrick and Jamie Sorcher break down the leading explanations: perhaps the cosmos is simply too vast for signals or craft to cross paths regularly, or perhaps advanced civilizations deliberately avoid broadcasting their presence after observing potentially dangerous behavior from younger species like ours.

Corbet’s paper takes a pragmatic view. Rather than invoking cloaked starships or interstellar empires, it emphasizes the hard limits imposed by physics. Electromagnetic signals and other emissions weaken dramatically across light-years, so even powerful transmissions can become undetectable by the time they reach us.

"A universe teeming with life could still be effectively silent to our instruments because emissions fade with distance and noise, and civilizations may choose discretion over contact," Corbet writes (as discussed in the Popular Mechanics piece).

Why This Matters

Whether silence arises from deliberate concealment or unavoidable physical limits, the result is the same: searches for extraterrestrial intelligence (SETI) face severe technical and conceptual challenges. The discussion reframes the mystery as both a behavioral puzzle—why would aliens hide?—and an engineering problem—how can we detect exceedingly faint or rare signals?

For those curious, editors Gilpatrick and Sorcher unpack the arguments and implications in an episode of "The Astounding Pop Mech Show," placing Corbet’s paper in the context of ongoing SETI efforts and the broader debate about humanity’s place in the cosmos.

Bottom line: A silent universe doesn't prove we're alone; it may simply reflect scale, stealth, or the physics that govern every signal traveling between the stars.