IMAGE: This image shows an artist’s view of winds in the Jupiter stratosphere near the planet’s south pole, with the blue lines representing wind speed. These lines are taken over by a real … more
Credit: ESO / L. Calçada & NASA / JPL-Caltech / SwRI / MSSS
Using the Atacama Large Millimeter / Submillimeter Array (ALMA), in which the Southern European Observatory (ESO) is a partner, a team of astronauts has measured winds directly in the central sense of Jupiter for the first time. hour. By analyzing what happened after a comet crash from the 1990s, the researchers have revealed incredibly powerful winds, with speeds of up to 1450 kilometers per hour, near the poles of Jupiter. They could represent what the team describes as a “specific epistemological beast in our Solar System”.
Jupiter is famous for its distinctive red and white bands: moving clouds of moving gas that astronauts traditionally use to monitor winds in Jupiter’s low atmosphere. Astronomers have also seen, near the poles of Jupiter, a vivid cry called aurorae, which appears to be associated with strong winds in the planet’s upper atmosphere. But until now, researchers have never been able to measure wind patterns between these two atmospheric layers, in the stratosphere.
It is impossible to measure wind speed in the Jupiter stratosphere using cloud detection methods because there are no clouds in this part of the atmosphere. However, astronauts were provided with other measurement support in the form of the comet Shoemaker-Levy 9, which hit the gas giant in incredible fashion in 1994. This effect brought new molecules into the Jupiter stratosphere, where they have ever moving with the winds. since then.
A team of astronomers, led by Thibault Cavalié of the Laboratoire d’Astrophysique de Bordeaux in France, have now discovered one of these molecules – hydrogen cyanide – to measure stratospheric “jets” on Jupiter. Scientists use the word “jets” to describe narrow wind bands in the atmosphere, such as the Earth’s jet streams.
“The most striking result is the presence of strong jets, with distances of up to 400 meters per second, located under the aurorae near the poles,” says Cavalié. These wind speeds, equivalent to about 1450 kilometers per hour, are more than twice the maximum storm speeds reached in Jupiter’s big red spot and more than three times the wind speed measured on the strongest tornadoes on Earth.
“Our discovery shows that these jets could behave like a giant vortex with a diameter of up to four times the size of Earth, and about 900 kilometers high,” explained the co-author. Bilal Benmahi, also of the Laboratoire d’Astrophysique de Bordeaux. “A vortex of this size would be a unique epidemiological beast in our Solar System,” Cavalié adds.
Astronomers were aware of strong winds near the poles of Jupiter, but much higher up in the atmosphere, hundreds of kilometers above the focus area of the new study, published today in Astronomy & Astrophysics. Previous studies predicted that these high-altitude winds would decrease in speed and disappear well before reaching as deep as the stratosphere. “The new ALMA data tells us otherwise,” Cavalié said, adding that finding these strong stratospheric winds near the poles of Jupiter was a “real surprise”.
The team used 42 of 66 high-precision ALMA antennas, located in the Atacama Desert in northern Chile, to study the hydrogen cyanide molecules that have been moving around in the Jupiter stratosphere from impact Shoemaker-Levy 9. The ALMA data allowed them to measure Doppler motion – tiny changes in the frequency of radiation emitted by the molecules – caused by the winds in this area of the planet. “By measuring this movement, we were able to reduce the wind speed so that one could reduce the speed of a passing train by changing the frequency of the train whistle,” explained co. study author Vincent Hue, planetary scientist. at the Southwestern Research Institute in the USA.
In addition to the spectacular polar winds, the team also used ALMA to confirm strong stratospheric winds around the planet’s equator, by measuring their speed directly, also for the first time. The jets seen in this part of the planet have an average speed of about 600 kilometers per hour.
The ALMA observations required to monitor stratospheric winds in both Jupiter’s poles and equator gave less than 30 minutes of telescope time. “The high levels of detail we have achieved in this short time certainly demonstrate the power of ALMA’s ideas,” said Thomas Greathouse, a scientist at the Southwestern U.S. Research Institute and co-author the study. “I’m surprised to see the first direct measurement of those winds.”
“These ALMA results open a new window for the study of Jupiter’s auroral regions, something that was only expected a few months ago,” Cavalié said. “They also set the stage for making similar but broader measurements with JUICE’s mission and its Wave Submillimetre Instrument,” adds Greathouse, referring to the European Space Agency’s JUpiter ICy moons Explorer , which is expected to launch into space next year.
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The huge ESO-based telescope (ELT), seen for the first time to see light later this decade, will study Jupiter. The telescope will be able to take very detailed views of the planet’s aurorae, giving us more insight into the atmosphere of Jupiter.
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This research is presented in the paper “First direct measurement of auroral and equatorial jets in the Jupiter stratosphere” published today in Astronomy & Astronomy (doi: 10.1051 / 0004-6361 / 202140330 – https: /
The team consists of T. Cavalié (Laboratoire d’Astrophysique de Bordeaux [LAB], France, and LESIA, Observatoire de Paris, PSL Research University [LESIA], France), B. Benmahi (LAB), V. Hue (Southwest Research Institute) [SwRI], USA), R. Moreno (LESIA), E. Lellouch (LESIA), T. Fouchet (LESIA), P. Hartogh (Max-Planck-Institut für Sonnensystemforschung [MPS], Germany), L. Rezac (MPS), TK Greathouse (SwRI), GR Gladstone (SwRI), JA Sinclair (Jet Dedication Laboratory, California Institute of Technology, USA), M. Dobrijevic (LAB), F. Billebaud (LAB) and C. Jarchow (MPS).
ESO is the most advanced intergovernmental astronomy organization in Europe and by far the most fertile land-based astronomical observatory. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, and the Netherlands. Sweden, Switzerland and the United Kingdom, along with the host state of Chile. and with Australia as a Strategic Partner. ESO conducts an advanced program aimed at the design, construction and operation of powerful ground-based observation facilities enabling astronauts to make important scientific discoveries. ESO also plays a key role in promoting and facilitating collaboration in astronomical research. ESO operates three world-class observation sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the world-leading Very Large Telescope and Very Large Telescope Interferometer as well as two monitoring telescopes, VISTA operates in the infrared VLT Inspection telescope and visible light. Also at Paranal ESO will host and operate the Cherenkov Array South Telescope, the largest and most sensitive gamma-ray observatory in the world. ESO is also a key partner in two facilities on Chajnantor, APEX and ALMA, the largest space project. And on Cerro Armazones, near Paranal, ESO is building the massive 39-meter Telescope, the ELT, which will become “the world’s largest eye on the sky”.
The Atacama Large Millimeter / Submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and Japan’s National Institutes of Natural Sciences (NINS) in collaboration with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in collaboration with the National Research Council of Canada (NRC) and Ministry of Science and Technology (MOST) and by NINS in collaboration with the Academia Sinica ( AS) in Taiwan and the Korea Institute of Astronomy and Space Science (KASI). The construction and operation of ALMA is managed by ESO on behalf of the Member States; with the National Radio Astronomical Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the Japan National Astronomical Observatory (NAOJ) on behalf of East Asia. The ALMA Joint Observatory (JAO) provides unified leadership and management of the construction, commissioning and operation of ALMA.
Links
* Research paper – https: /
* Images of ALMA – https: /
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Please contact
Thibault Cavalié
Laboratoire d’Astrophysique de Bordeaux
Bordeaux, France
Phone: +33 (0) 5 40 00 32 71
Email: [email protected]
Bilal Benmahi
Laboratoire d’Astrophysique de Bordeaux
Bordeaux, France
Phone: +33 (0) 5 40 00 32 76
Email: [email protected]
Vincent Hue
Southwest Research Institute
San Antonio, TX, USA
Phone: +1 (210) 522-5027
Email: [email protected]
Thomas Greathouse
Southwest Research Institute
San Antonio, TX, USA
Phone: +1 (210) 522-2809
Email: [email protected]
Suzanna Randall
(astronaut who did not take part in the survey; contact for external comments and questions on ALMA)
Southern European Observatory
Garching bei Munich, Germany
Email: [email protected]
Bárbara Ferreira
ESO Media Manager
Garching bei Munich, Germany
Phone: +49 89 3200 6670
Cell: +49 151 241 664 00
Email: [email protected]