Astronomers have finally measured the speed of stratospheric winds at Jupiter’s South Pole. These currents travel at speeds of up to 1,450 kilometers (900 miles) per hour – twice as fast as the wind at Jupiter’s Great Red Spot and nearly four times as fast as the fastest wind recorded on Earth. As mentioned in Astronomy and Astronomy, this measurement requires an Atacama Large Millimeter / submillimeter Array (ALMA), one of the most sophisticated observatories on the planet. However, that alone was not enough.
The observations made thanks to a clear phenomenon: a comet colliding with Jupiter. Back in 1994, Comet shoe maker-Levi 9 hit by gas giant. The event released molecules into the Jovian atmosphere that lasted to this day. The researchers were able to track those molecules and measure how fast they moved. Jupiter’s stratosphere is cloudless, so without these molecules researchers would not be able to measure air.
The team found that polar planes are much faster than stratospheric winds in the equatorial region, where they are about 600 kilometers an hour. Observations reveal the incredible amount and depth at which the stratospheric jet reaches the pole. Said in a statement, “Our detection indicates that these planes can behave like giant whirlpools, about 900 kilometers in diameter and length, four times larger than Earth’s,” said co-author Bilal Benmahi, from the Laboratoire d’Astrophysique de Bordeaux.
“A vortex of this size could be a unique weather animal in our solar system,” added Thibault Cavalié also from the Laboratoire d’Astrophysique de Bordeaux. From this study, it understood that much could learn about Jupiter from Earth. One of the most exciting things is that it took only 30 minutes of observation time from ALMA to get these results – this is a very short time for astronomical observations. Thomas Greathouse, a scientist at the Southwestern Research Institute in the United States and co-author of the study, said:
“I was surprised to see the first direct measurement of this wind.” The European Space Agency’s Jupiter IC Moon Explorer (GUIS) will be equipped with a submillimeter light device that will be able to make these observations very close. It will launch next year and expected to reach Jupiter in 2029.
