A planet discovered in 2014 may be the darkest celestial body ever found, say researchers in the astrophysics group at Keele University, UK. There’s a planet the size of Jupiter whipping around star 466 light-years away from Earth named WASP-104b. Researchers have suggested that it is probably a glowing purplish ember. They don’t know for sure because the massive, gassy world is one of the darkest planets astronomers have ever detected. It is ‘darker than charcoal’ that the researchers cannot see the planet and it may swallow up to 99% of the light its local stars shed upon it. It can be counted as one of the top three darkest planets existing.
Hot Jupiters are a class of gas giants that have a mass similar that to Jupiter and stay close and orbit their stars in less than 10 days. Planets like WASP-104b are called hot Jupiters because they orbit extremely close their host stars, resulting in searing surface temperatures. Researchers did not discover WASP-104b, but they did bring its impressive darkness to light after poring over data provided by the Kepler space telescope. They studied the planet via the transit method which involves measuring the minute dimming of a distant star as a planet passes in front of it. WASP-104b is tidally locked – one side always faces the star and the other side is cooler and darker.
The research paper says that the planet is one of the least-reflective planets found to date. The paper suggests that the planet’s reflective clouds have burnt off due to extreme proximity to its hot star and rules out any highly reflective clouds in WASP-10b’s atmosphere. Theoretical atmosphere models suggest that the hazy layer around the planet is thick with atomic sodium and potassium that absorb all light around it. In other words, the distance between the planet and its star is an important factor in how dark it is.
While WASP-104b might appear blacker than coal, it likely has a distinct underlying colour that Earth-bound observers just can’t perceive. Incoming solar radiation probably causes the planet to glow – maybe dark purple like a bruise or red like ember – but from 466 light-years away, scientists just can’t tell. The new finding adds to dark planets that have been discovered previously. TrES-2b is one of very few hot Jupiters at least as dark as WASP-104b. It orbits roughly three million miles from its hot, reflecting less than one percent of any light that hits it.