Astronomers Characterize HD 189733b With 7,000 km/h Winds and 1,000°C Glass Rain
Updated
Updated · spacedaily.com · Jun 2
Astronomers Characterize HD 189733b With 7,000 km/h Winds and 1,000°C Glass Rain
1 articles · Updated · spacedaily.com · Jun 2
HD 189733b, a hot Jupiter 63 light-years away, has emerged as one of the best-characterized exoplanets, with studies describing a tidally locked world where the day side reaches about 1,000°C.
A roughly 260°C day-night temperature gap drives upper-atmosphere winds near 7,000 km/h, while silicate material condenses into molten glass droplets that are blown sideways as continuous horizontal rain.
Hubble measurements in 2013 isolated the planet’s reflected light during secondary eclipses and found it reflects blue wavelengths about three to four times more strongly than red, giving it a deep cobalt appearance.
That blue color does not come from oceans but from light scattering off silicate particles in the superheated atmosphere, making the planet resemble Earth visually while remaining physically hostile.
Discovered in 2005 and orbiting its star every 2.2 days at just 4.6 million km, HD 189733b has become a benchmark hot Jupiter for probing how giant planets form, migrate and evolve.
Did the 'glass rain' planet violently eject its siblings to get so close to its star?
Since JWST found water on a world of molten glass, what other chemical impossibilities will it uncover in deep space?
With models now questioned, is our picture of a 'glass rain' world fundamentally wrong?
HD 189733b in Focus: New Atmospheric Insights, Sulfur Chemistry, and Supersonic Glass Rain (2024–2026)
Overview
Between 2024 and 2026, astronomers made major breakthroughs in studying HD 189733b, a gas giant about 64 light-years away in Vulpecula. In July 2024, new observations revealed that this planet orbits extremely close to its star—13 times closer than Mercury is to the Sun—completing a full orbit in just two days. These conditions create scorching temperatures up to 1,700 degrees Fahrenheit, hot enough to melt rock into magma. These discoveries have greatly improved our understanding of HD 189733b’s extreme atmosphere and highlight its value as a benchmark for exoplanet research.