Researchers from Portugal have achieved a notable milestone by using the European Southern Observatory’s Very Large Telescope for a solar system study, marking the first time this facility has been employed to investigate a planet within our own system rather than distant exoplanets. The work, conducted by scientists at the Institute of Astrophysics and Space Sciences of the University of Lisbon, has been documented in a scientific journal that highlights advancements in planetary atmospheres and observational techniques. This achievement showcases how state-of-the-art ground-based astronomy can contribute directly to our understanding of the planets that orbit the Sun.
Traditionally, the VLT is renowned for hunting for worlds beyond our solar system, but its instrumentation proves equally powerful for close-up planetary meteorology. The team leveraged the telescope’s ESPRESSO spectrograph, a high-precision instrument designed to analyze light with exceptional fidelity, to measure wind patterns in Jupiter’s atmosphere. The results indicate jet-like winds reaching about 428 kilometers per hour, with a margin of error notably small at under 36 kilometers per hour. This level of precision enables researchers to refine models of atmospheric circulation on gas giants and to compare them with observations made by other facilities and missions. [Cited: University of Lisbon researchers and ESO instrumentation notes]
In describing Jupiter’s cloud deck, the scientists explain that the planet’s atmosphere contains ammonia, ammonium hydrosulfide, and water. These constituents condense to form color bands and streaks visible from Earth. The upper clouds in the pressure range corresponding to 0.6 to 0.9 bar are dominated by ammonia ice, while water clouds occupy the deeper, denser levels and exert a strong influence on atmospheric dynamics. This layered structure helps explain how heat and momentum are transported within the planet’s atmosphere, shaping the large-scale weather patterns seen from our vantage point. Pedro Machado, one of the researchers involved in the study, emphasizes the role of these chemical species in governing cloud formation and atmospheric motion. [Cited: University of Lisbon team member statements and atmospheric composition analyses]
The researchers outline plans to broaden ESPRESSO-based observations to cover a larger fraction of Jupiter’s disk. By extending the data collection during the planet’s roughly ten-hour rotation, they aim to obtain a more complete picture of wind distribution and its temporal evolution. The enhanced coverage will also support cross-comparison with measurements from other observatories and space missions, enriching the context for interpreting atmospheric dynamics on gas giants. [Cited: project roadmap and ESPRESSO capabilities]
Looking ahead, the team intends to apply the same high-precision spectroscopic approach to other giant planets. Following Jupiter, Saturn has been identified as the next primary target for these measurements, with the goal of revealing how atmospheric dynamics scale across the family of gas giants. The work with the VLT and ESPRESSO demonstrates how terrestrial facilities can complement space-based explorers, offering detailed wind and composition data that feed into broader planetary science. [Cited: future target planning and collaboration notes]
In related developments, preparatory discussions have continued about large-scale space observatories and their technology demonstrations. Prospects surrounding the launch of the Einstein Space Telescope include innovative camera designs that aim to expand the observational frontier. The reference to this telescope underscores the broader context of modern astronomy where advancing detector technology and precise measurement techniques work in concert to deepen our understanding of both nearby planets and far-off cosmic phenomena. [Cited: astronomy infrastructure and mission planning summaries]