'60 light-years away': NASA’s James Webb Telescope captures coldest exoplanet in distant star system

NASA’s James Webb Space Telescope has recently captured an image of one of the coldest known exoplanets ever observed. Located around 60 light-years from Earth, this planet has been named 14 Herculis c. It is roughly seven times the mass of Jupiter and it orbits a star within the Milky way galaxy called 14 Herculis.

'Abnormal, chaotic and strange' are just a few adjectives astronomers are using to describe this exoplanet. 14 Herculis c stands out due to its exceptionally low temperature, which is about 26 degrees Fahrenheit (minus 3 degrees Celsius). This is said to be unusual as most directly imaged exoplanets tend to be have extremely high temperatures, some often reaching thousands of degrees.

This planet was imaged using Webb’s Near-Infrared Camera (NIRCam), which detects reflected infrared light. The observation portrays a new capability of the Webb telescope, allowing scientists to study not just hot, young planets but even older and much colder ones in the galaxy and beyond.

14 Herculis is said to host two known planets. The orbits of these planets, however, are not aligned on the same plane, something which is rare in our solar system. Instead, their orbital paths cross at an angle of approximately 40 degrees, thus making the system structurally unusual. One of the many theories suggests the system may have once contained a third planet that was later ejected, causing this misalignment.

14 Herculis c is located about 1.4 billion miles from its star and it follows a highly elliptical orbit. This is said to be approximately 15 times the Earth’s distance from the Sun. This places it between Saturn and Uranus in scale, though in a much colder context.

Another interesting fact observed is, the planet’s faint brightness in Webb’s infrared image, suggesting that it is cooler than expected for a planet of its mass and age. The planet’s brightness is at 4.4 microns, measured using Webb’s coronagraph. It is believed that the reason for this appearance might be due to carbon disequilibrium in the atmosphere. This happens when molecules like carbon dioxide and carbon monoxide persist instead of methane, due to rapid mixing between warmer lower layers and colder upper layers.

Researchers and scientists alike view this as the beginning of more detailed investigations into the 14 Herculis system. While there are nearly 6,000 exoplanets that have been discovered, only a small number of those have been directly imaged