Imagine spotting a tiny firefly fluttering next to a powerful lighthouse – that’s how difficult it is for astronomers to directly see a distant planet next to its bright star. But NASA’s James Webb Space Telescope (JWST) has achieved this feat again, capturing a direct image of a frigid world called 14 Herculis c. This discovery is significant because it images an older, colder exoplanet than usually possible and reveals it resides in a star system with dramatically misaligned planetary orbits, offering new clues about how solar systems form and evolve.
The exoplanet 14 Herculis c orbits a star similar to our sun, located about 60 light-years away in the constellation Hercules. Appearing as a faint, warm-hued dot in the new JWST image, this planet is estimated to be about 4 billion years old – roughly the same age as Earth. Its atmosphere is surprisingly cold, hovering around 26 degrees Fahrenheit (-3 degrees Celsius).
Diagram illustrating the tilted orbits of planets in the 14 Herculis star system compared to a flat plane.
14 Herculis c orbits its star at a vast distance, roughly 15 times farther than Earth is from the sun, or about 1.4 billion miles (2.2 billion kilometers). If placed in our own solar system, it would orbit between the gas giants Saturn and Uranus.
However, unlike the neat, relatively flat paths of planets in our neighborhood, the 14 Herculis system is chaotic. The two known planets, including 14 Her c, orbit at angles of about 40 degrees relative to each other, forming an “X” pattern around their star.
Astronomers believe this strange, tilted configuration might be the result of a turbulent past, perhaps involving the gravitational scattering or ejection of a third massive planet early in the system’s history. This event could have thrown the remaining two planets into a kind of gravitational “tug of war,” leaving them in their current, misaligned dance.
Why a Tilted Orbit Helps Webb See the Planet
Imaging planets directly is incredibly challenging. Planets are far dimmer than their host stars – millions or billions of times fainter – making them incredibly hard to pick out of the glare. Most directly imaged exoplanets found before JWST were young, hot gas giants that emitted enough infrared light to be detectable. Older, colder planets like 14 Her c are usually too faint.
James Webb Space Telescope NIRCam image showing the exoplanet 14 Herculis c as a faint dot near its host star, blocked by a coronagraph.
Yet, the weird, tilted orbit of 14 Her c turned out to be an advantage for the research team led by astronomer W. Balmer. Because of its unusual path, they could precisely predict its position, making it an ideal target for direct imaging using JWST’s powerful instruments.
Using a specialized tool on Webb called a coronagraph – which works like a sunshade to block the star’s blinding light – the team successfully isolated the faint infrared glow of 14 Her c. This allowed them to directly image an older, colder exoplanet than previously possible with direct imaging techniques.
Peering into a Cold Atmosphere
Based on the planet’s estimated age (4 billion years) and mass (about seven times that of Jupiter), computer models predicted 14 Her c should be warmer and brighter than it appeared in the JWST image. The planet was unexpectedly faint.
By analyzing the light from its atmosphere, JWST detected carbon dioxide and carbon monoxide. At the planet’s temperature, methane would typically be expected, but its apparent absence suggests something unusual is happening. Scientists propose that strong currents or “updrafts” within the atmosphere might be carrying hot gases from deep below to the colder upper layers. These gases, possibly combined with thin, icy clouds, could be trapping heat and preventing it from escaping, making the planet appear cooler and fainter than the models predicted.
Why This Matters
Discovering and studying planets like 14 Herculis c expands the types of worlds astronomers can investigate directly. By examining exoplanets with vastly different masses, temperatures, and orbital configurations – especially strange ones like this – scientists gain crucial data points. This helps them refine models of how planetary systems are born, how they evolve over billions of years, and what kinds of chaotic events can shape their final structures.
Understanding the diversity of systems out there brings us closer to understanding the story of planet formation itself, and in turn, how our own familiar solar system came to be.
To learn more about these incredible distant worlds, check out:
- Exoplanets: Everything you need to know about the worlds beyond our solar system
- James Webb Space Telescope (JWST) — A complete guide
