Scientists have discovered the fastest known jet stream, with winds reaching a staggering 20,500 miles per hour (33,000 km/h).
The winds on the exoplanet WASP-127b make even Neptune’s impressive 1,200 miles per hour winds seem like a gentle breeze, and Earth’s 275 mph barely a breath. The discovery sets a new record for the fastest jet stream winds observed on any planet.
Located 520 light-years from Earth, in a tight orbit around a star similar to our sun, WASP-127b is a gaseous giant orbiting a sun-like star in our Milky Way galaxy.
The supersonic winds are concentrated around WASP-127b’s equator, further adding to the planet’s unusual characteristics.
While Earth’s jet stream plays a crucial role in our weather patterns, the impact of these extreme winds on WASP-127b’s atmospheric dynamics remains a subject of ongoing research.
“There is an extremely fast circumplanetary jet wind found on the planet. The velocity of the winds is surprisingly high,” said astrophysicist Lisa Nortmann of the University of Gottingen in Germany, lead author of the study published on Tuesday in the journal Astronomy & Astrophysics.
More than 5,800 planets beyond our solar system – called exoplanets – have been discovered. WASP-127b is a type called a “hot Jupiter,” a gas giant that orbits very close to its host star. WASP-127b’s diameter is about 30% larger than Jupiter, our solar system’s largest planet. But its mass is only about 16% that of Jupiter, making it one of the least dense – puffiest – planets ever observed.
“WASP-127b is a gas giant planet, which means that it has no rocky or solid surface beneath its atmospheric layers. Instead, below the observed atmosphere lies gas that becomes denser and more pressurized the deeper one goes into the planet,” said astrophysicist and study co-author David Cont of Ludwig Maximilian University of Munich in Germany.
It orbits its star every roughly four days at just about 5% of the distance between Earth and the sun, leaving it scorched by stellar radiation. Like our moon is to Earth, one side of WASP-127b perpetually faces its star – the day side. The other side always faces away – the night side. Its atmosphere is about 2,060 degrees Fahrenheit (1,400 degrees Kelvin/1,127 degrees Celsius), with its polar regions less hot than the rest.
Like Jupiter, WASP-127b is composed mainly of hydrogen and helium, but its atmosphere also contains traces of more complex molecules such as carbon monoxide and water, which were identified in this research.
The fact that a hot Jupiter’s day side is highly irradiated is believed to be a major driver of atmospheric dynamics.
“Answering the question of what drives these intense winds is challenging, as several factors influence wind patterns in exoplanet atmospheres,” Cont said.
“The primary source of energy for these winds is the intense irradiation from the host star,” Cont added, but other factors also play an important role in shaping the wind patterns.
Higher atmospheric wind speeds have been detected on two other exoplanets, in winds from their day side to night side, but not in winds flowing around the entire planet.
The researchers tracked the speed of molecules in the planet’s atmosphere using an instrument called CRIRES+ on the European Southern Observatory’s Chile-based Very Large Telescope. They made the observations using the “transit” method, observing changes in the host star’s brightness when the planet passes in front of it, from the perspective of a viewer on Earth.
With improvements in instrumentation, observational techniques and data analysis, researchers are better able to understand exoplanets’ atmospheres.
