Image credit: NASA, Juno Spacecraft
A team of astronomers was able to measure for the first time powerful winds in Jupiter’s stratosphere, the layer between the lower and upper atmospheres. Some of these jets reach speeds of up to 1,450 kilometers per hour. These measurements were made at the poles and were made possible by ALMA’s array of antennas from the Atacama desert in Chile.
Jupiter, the gas giant planet, is famous for its red and white gas bands, these like clouds that move in opposite directions and in certain places swirl incessantly.
Astronomers track these clouds to measure the winds in the giant planet’s lower atmosphere. Bright auroras that appear to be associated with strong winds in the upper atmosphere have also been observed near the poles, but these wind jets that occur between these two atmospheric layers have not been directly measured until now, in the stratosphere, since in this area, 900 kilometers high, there are no clouds.
A team of astronomers, led by Thibault Cavalié from the Bordeaux Astrophysics Laboratory, in France, has managed for the first time to measure strong jets at Jupiter’s poles, with speeds of up to 400 meters per second or 1450 kilometers per hour, which could represent, as the team has described it, a “unique weather beast in our solar system.”
In order to measure winds in this region, astronomers studied hydrogen cyanide molecules caused by the spectacular impact of Comet Shoemaker-Levy 9 in 1994 and still moving in Jupiter’s stratosphere.
The team used 42 of the 66 ALMA antennas, located in the Atacama desert, in northern Chile. The Southwest Research Institute of San Antonio Texas, known for its studies of Jupiter also participated in this project, the French astronomer Vincent Hue from this institute explains: “Thanks to ALMA and spectroscopy, which means the detailed study of light, They can measure many things, such as the number of molecules in the stratosphere, the temperature, and also the winds. This is how we were able to measure the winds ”.
Surprise for scientists
Finding those strong winds in this layer, about 900 kilometers high, was a real surprise for scientists and it was also the fact that these wind speeds were reached, equivalent to about 1450 kilometers per hour, more than double the maximum speeds. of storm reached in the Great Red Spot of Jupiter and more than triple the wind speed recorded in the strongest tornadoes on our planet earth.
Astronomers were aware of the strong winds near Jupiter’s poles, but in a much higher part of the atmosphere, hundreds of kilometers above the area in which this new study is focused, entitled “First direct measurement of auroral an equatorial jets in the strastosphere of Jupiter ”and published in the journal Astronomy & Astrophysics.