Recent findings show that Jupiter is smaller and flatter than scientists once believed. A study published in Nature Astronomy reveals new measurements based on data gathered by NASA’s Juno spacecraft. This is a shift from earlier data collected about 50 years ago by missions like Voyager and Pioneer.
Using improved radio measurements, researchers now say Jupiter’s polar radius is approximately 41,534 miles, which is about 7.5 miles less than previous estimates. Similarly, its equatorial radius is now calculated at 44,421 miles—2.5 miles smaller than before. According to planetary scientist Yohai Kaspi, “the size of Jupiter hasn’t changed, but the way we measure it has.” These refined measurements enhance our models of Jupiter’s interior and can also shed light on gas giants outside our solar system.
Juno, which has been exploring Jupiter since 2016, collected substantial new radio data, allowing scientists to analyze how signals bent as they traveled through Jupiter’s atmosphere. This bending effect helps researchers understand the planet’s complex atmosphere and the forces at play, improving the accuracy of their size calculations.
Why do these small changes matter? According to Eli Galanti, also from the Weizmann Institute, even minor adjustments in size can significantly refine models that predict Jupiter’s internal structure. This is important not just for Jupiter, but also for understanding how gas giants form and evolve in general. As Kaspi notes, “Jupiter was likely the first planet in our solar system.” Learning more about it gives us clues about the formation of other worlds.
This study comes at a time when the interest in gas giants is piqued, partly due to recent missions aimed at studying exoplanets. For instance, the James Webb Space Telescope has been providing remarkable insights into celestial bodies far beyond our solar system, leading to increased discussions about the nature of these distant worlds.
In conclusion, while our understanding of Jupiter might seem slightly altered, it actually opens doors to deeper discoveries about our universe. By refining measurements and models, scientists continue to unveil the mysteries of the giant planets, both near and far.
For more details, you can read the full study in Nature.
