The Sun Is the Prime Suspect in a Missing Planet Case

Something about 5.6 times the mass of Earth may have spiraled into the young sun billions of years ago. According to new research, the evidence could still be in there, buried deep and throwing off the measurements.

The study, published in Monthly Notices of the Royal Astronomical Society, proposes that this ancient planetary ingestion could explain several long-standing mysteries that current models cannot fully account for: the sun's unusually low surface lithium levels, the depth of its convection zone and subtle differences between the sun's observed internal structure and what stellar evolution models predict.

The lithium problem is the strange one. The sun's lithium levels are roughly 100 times lower than primordial estimates. Then there's the convection zone, the layer under the surface where hot gas churns. Sound moves through the bottom of it at a speed the best solar models can't reproduce.

Mutlu Yildiz, a professor at Ege University in Turkey, wondered whether both could trace back to one event, a planet swallowed early in the sun's life whose remains are still altering its interior. The planet in his models has a name, Dev Dilek, Turkish for "Great Wish."

Yildiz concedes the case may never be proved outright. The search isn't for the planet itself but for its ghostly signature buried within the sun's structure. If other researchers can detect those predicted fingerprints on their own, that would be the closest thing to a confession we're likely to get.

If Yildiz is right, a world died inside our star and never left. We've been orbiting the crime scene for about 4.5 billion years.

Read the full story at Universe Today, September 17, 2026

Hot Take: Astronomers hunt for planets around thousands of distant stars. Nobody thought to frisk our own.