Webb finds never-before-seen structures above Jupiter’s Great Red Spot – NASASpaceFlight.com

by

Using the joint NASA, European Space Agency (ESA) and Canadian Space Agency (CSA) James Webb Space Telescope, a group of scientists have discovered a variety of never-before-seen features in Jupiter’s upper atmosphere. The features were found in the atmospheric region above the iconic Great Red Spot, a high-pressure area in Jupiter’s atmosphere that creates a massive anticyclonic storm that has been visible to astronomers since 1831.

Before the last observations of the region, scientists believed that the region was unremarkable and lacked any complex atmospheric structures or activity. However, Webb has shown that the region is scientifically interesting, and is already giving scientists more insight into the inner workings of Jupiter and its vast atmosphere.

Although it may seem simple, it is difficult to observe Jupiter in much detail using huge telescopes such as Webb and Hubble. The glow of Jupiter’s upper atmosphere is dim compared to the glow of the planet’s northern and southern polar regions, meaning that visible-light telescopes like Hubble and some ground-based telescopes have a harder time spotting specific structures in the planet’s upper atmosphere. observe. However, given Webb’s sensitivity to infrared light, the telescope can observe the upper atmosphere without interference from the planet’s bright polar regions. Furthermore, Webb’s advanced technology and size mean it can not only collect upper atmosphere data, but do so in unprecedented detail.

Webb’s observations of the area around the Great Red Spot. (Credit: ESA/Webb/NASA/CSA/Jupiter ERS Team/J. Schmidt/H. Melin/M. Zamani (ESA/Webb))

Jupiter’s upper atmosphere forms the boundary between the planet’s immense magnetic field and the inner atmosphere, and its structure is largely shaped by the interaction between the two regions. For example, the upper atmosphere, with some help from volcanic material ejected from the moon Io, produces bright auroras and auroras. Closer to the planet’s equator, however, the atmospheric structure is largely determined by incoming sunlight, and since Jupiter receives only four percent of the sunlight that Earth receives, scientists predicted that this region would be less complex than the more northerly and southerly regions of the upper atmosphere.

However, this was only a hypothesis by the scientists, as observations needed to determine the structure of the upper atmosphere in equatorial regions were not yet available – that was until Webb’s debut in 2022.

Webb first observed the equatorial regions of the upper atmosphere, specifically a region above the Great Red Spot, in July 2022 using the Integral Field Unit capabilities of the Near-Infrared Spectrograph (NIRSpec) instrument. The team of scientists’ main goal with the observations was to examine the region and determine whether the area was dim, as scientists previously thought.

When Webb returned his observations and data to the team, they were surprised to see that the entire region above the Great Red Spot is home to a variety of intricate structures and activity, including dark arcs and bright spots.

“We thought, perhaps naively, that this region would be very boring. In fact, it is as interesting as the Northern Lights, or even more so. Jupiter continues to surprise,” said lead author Henrik Melin of the University of Leicester in the United Kingdom.

Much of the light emitted from this area is reflected sunlight. However, some structures and activities discovered in this area appear to have been changed by a mechanism other than sunlight.

“One way you can change this structure is through gravitational waves – similar to waves crashing on a beach and causing ripples in the sand. These waves are generated deep in the turbulent lower atmosphere, around the Great Red Spot, and they can travel into moving altitude, changing the structure and emissions of the upper atmosphere,” Melin explained.

The atmosphere surrounding the Great Red Spot, as imaged by NIRSpec. (Credit: ESA/Webb/NASA/CSA/H. Melin/M. Zamani (ESA/Webb))

Melin et al. explain in their study that these atmospheric waves can sometimes be observed on Earth. However, the waves that occur on Earth are much weaker than those observed by Webb on Jupiter. The team plans to perform follow-up observations of these atmospheric wave patterns to investigate how the waves travel through Jupiter’s upper atmosphere. Furthermore, understanding the wave patterns will allow scientists to gain insight into how much energy is trapped in this region and how the structures discovered by Webb change over time.

Webb’s latest observations not only expand scientists’ understanding of Jupiter’s upper atmosphere, but will also help inform mission planning and future science observations from ESA’s Jupiter Icy Moons Explorer, or JUICE, mission. JUICE is currently en route to Jupiter, where it will explore the planet’s three largest ocean-bearing moons, Ganymede, Callisto and Europa.

The observations by Melin et al. were made as part of Webb’s Early Release Science (ERS) program 1373. The proposal for the observations was made in 2017 and was originally written to gain insight into the temperature above the Great Red Spot.

“This ERS proposal dates back to 2017. One of our objectives was to investigate why the temperature above the Great Red Spot appeared high, as recent observations with the NASA Infrared Telescope Facility showed at the time. However, our new data showed very different results,” says co-author Imke de Pater of the University of California, Berkeley.

The results of Melin et al. were published in the journal Nature Astronomy.

(Main image: Jupiter imaged in the near-infrared by Webb’s NIRCam instrument. Credit: NASA/ESA/CSA/Jupiter ERS Team/Ricardo Hueso (UPV/EHU)/Judy Schmidt)

Leave a Comment