An instrument designed to study outer planets has turned its attention to our own cosmic neighborhood to measure wind speed on Jupiter. Using the ESPRESSO spectrograph on the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in northern Chile, researchers analyzed changes in sunlight reflected from clouds in Jupiter’s atmosphere. By measuring the change in wavelength of reflected light, researchers were able to calculate the speed of Jupiter’s clouds relative to Earth. expression.

“The application of this method for exploratory purposes with a ‘highest range’ device such as ESPRESSO has broken new ground for understanding our cosmic neighborhood,” officials said in a statement. said. “This study confirms the feasibility of systematically monitoring the most distant atmospheres of gaseous planets.”

The ESPRESSO (Echelle Spectrograph for Rocky Exoplanets and Steady Spectroscopic Observations) instrument is designed to search for exoplanets or planets outside our solar system. Its main purpose is to study distant stars and look for changes in starlight that indicate the presence of an exoplanet.

In the new study, this technique, called Doppler velocimetry, was applied to sunlight reflected from clouds above Jupiter, the largest planet in our solar system. The VLT observed Jupiter for five hours in July 2019, focusing on the equatorial region, where clouds are higher and brighter, and the northern and southern equatorial zones, where clouds are darker and warmer and located deeper in the atmosphere. Measurements showed wind speeds at the gas giant ranged from 37 to 266 mph (60 to 428 km/h).

“Jupiter’s cloud-level atmosphere, visible from Earth, contains ammonia, ammonium hydrosulfide and water, forming distinctive red and white bands,” said study lead author Pedro Machado, of the University’s Institute of Astrophysics and Space Sciences (IA) in the Faculty of Science. In the statement, it was stated that he was in Lisbon, Portugal.

“The upper clouds in the pressure region between 0.6 and 0.9 bar are composed of ammonia ice,” Machado added. “Water clouds form the densest, lowest layer and have the strongest impact on atmospheric dynamics.”

Their findings, published Nov. 24 in the journal Universe, shed light on Jupiter’s atmospheric phenomena, including powerful storms like the Great Red Spot and string jet streams, and can also be applied to studies of other gas giants such as Saturn.