The weird metal-clouded shiny planet LTT9779 b is the largest known “mirror” in the cosmos because it reflects 80% of the light from its star.
The brightest shiny planet ever found is an odd exoplanet with metallic clouds that shower titanium onto its scorching interior, according to a recent study. Scientists claim that the Neptune-sized world “shouldn’t exist,” yet it does. The lustrous world functions as a big mirror, reflecting light back towards its star, which is situated unusually near to it.
Using NASA’s (TESS) spacecraft
Researchers using NASA’s Transiting Exoplanet Survey Satellite (TESS) spacecraft found the exoplanet, known as LTT9779 b, in 2020. The gas giant, which orbits its sun-like star every 19 hours and is located around 260 light-years from Earth, is about five times as large as our planet. Ultrashort-period planets are exoplanets with orbital periods smaller than one day on Earth, which are found in only 1 in 200 sun-like star systems.
With the help of the Characterising Exoplanet Satellite (Cheops) satellite from the European Space Agency, researchers examined LTT9779 b in further detail for a recent study that was published on July 10 in the journal Astronomy and Astrophysics. The scientists discovered that the planet’s sun-facing side reflects almost 80% of the starlight that strikes it, making it the most reflective shiny planet ever seen in terms of albedo.
Considering that Earth is primarily covered by water and has highly reflecting polar caps, only about 30% of the sunlight that strikes our globe is reflected by our planet.
Prevent Cloud Formation
The metallic clouds surrounding LTT9779 b are thought to be the source of the planet’s high albedo and are primarily composed of titanate, a salt containing titanium, and silicate, or glass. When the exoplanet was first discovered, scientists believed that its close proximity to its star would prevent cloud formation because the shiny planet’s atmosphere likely reaches scorching temperatures above 3,600 degrees Fahrenheit (2,000 degrees Celsius), making it too hot for these materials to condense into a cloud.
But silicate and titanate gases are probably so abundant in the planet’s atmosphere that they can condense into liquids, just as water vapor might condense into mini-clouds in a bathroom if the shower is left running for a long enough time, according to the study’s authors.
The metallic clouds of LTT9779 b also account for another perplexing feature of the exoplanet, its size. All ultrashort-period planets that have been discovered so far are either rocky planets no bigger than Earth or gas giants much larger than Jupiter. Smaller gas giants like LTT9779 b were thought to be impossible to live in such close proximity to their home star, according to researchers.
“It’s a shiny planet that shouldn’t exist,” research co-author Vivien Parmentier, an astrophysicist at the Côte d’Azur Observatory in France and the University of Oxford in the U.K., said in a statement. “We anticipate atmospheres on planets like this to be blown away by their star, leaving only bare rock behind.”
