Peering at the Edges of Distant Stars

By Space.Fan Editorial DeskSeptember 19, 2026 at 11:01 PM UTC

Scientists used a special telescope array to map the hidden edges of 31 stars, revealing that our current math models need a big update.

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The Drop

s are not just uniform balls of light. If you look closely, the center of a appears brighter than its edges. This effect is called limb darkening. Because the light at the edge of a has to travel through more atmosphere to reach us, it looks cooler and dimmer. While scientists have long known about this, getting an accurate picture of it has been difficult. A team of researchers used the CHARA Array, a group of powerful telescopes in California, to get a better look. By combining light from different telescopes, they created a zoom effect that allowed them to study the surfaces of 31 s in great detail. They specifically looked at two types of infrared light, known as H and K bands. After measuring these s, the team compared their findings to existing computer models. They found that the way the light fades at the edges does not match what the models predicted. The difference between the two light bands was much larger in the real s than the computer simulations suggested.

Why It Matters

This research is important because astronomers use these models to figure out the size and temperature of s. If our models are slightly wrong about how a looks at the edges, our calculations for things like the age of a or whether a might be orbiting it could be off, too. By providing real data, this study gives scientists a new benchmark to help fix and improve their computer programs.

The Catch

While the measurements were very precise, the study only looked at 31 specific s. Because s come in many different sizes and types, this small sample may not tell the whole story for every type of in the universe. Additionally, even though the team checked their work, there is always a small chance that unseen factors in how the telescopes process light could play a role in the results.

Put That in Perspective

Historically, measuring the surfaces of distant stars was nearly impossible. With tools like the CHARA Array, astronomers are moving from making educated guesses to taking precise measurements of stellar geography. Future research will likely involve testing even more types of stars to see if this pattern holds up across the galaxy.

Source September 19, 2026

Narsireddy Anugu, John D. Monnier, Antoine Mérand, Becky Flores, Alexandre Gallenne, Douglas R. Gies, Mayra Gutierrez, Robert Klement, Stefan Kraus, Jayadev Rajagopal, Rachael M. Roettenbacher, Gail H. Schaefer

The CHARA Array of Georgia State University, University of Michigan, European Southern Observatory, Universidad de Tarapacá, Université Côte d’Azur, University of Exeter, NSF’s National Optical-Infrared Astronomy Research Laboratory·The Astronomical Journal·10.3847/1538-3881/ae9878