The same person appears differently depending on who is looking. The universe is the same. Saturn with its rings looked different to two space telescopes. The colors and shapes differed.
The National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) on the 25th (local time) released the sharpest images of Saturn taken by space telescopes to date. The James Webb and Hubble telescopes photographed the same Saturn in 2024 at three-month intervals.
◇Observed in infrared and visible light, respectively
The Hubble Space Telescope photographed Saturn on Aug. 22, 2024, as part of a long-term observation program of more than 10 years called OPAL (Outer Planet Atmospheres Legacy). The James Webb Space Telescope then took images of Saturn on Nov. 29 of the same year. With a three-month time gap, the rings appear at different angles.
Both space telescopes detected sunlight reflected by Saturn, but the images show different colors. In the James Webb Space Telescope image, Saturn as a whole appears orange, and the rings are wide and bright. The Hubble image is closer to yellow, and the rings are thinner and darker. The difference lies in the light captured by the two telescopes. The James Webb Space Telescope and the Hubble Space Telescope captured the infrared and visible ranges, respectively.
Astronomers said that while Hubble imagery revealed subtle color variations across Saturn, James Webb's infrared observations detected a variety of chemicals by altitude, from deep cloud layers to the rarefied upper atmosphere. The European Space Agency said that combining the images taken by the two telescopes allows scientists to observe Saturn's atmospheric cross-section by altitude, like peeling an onion.
In the image taken by the James Webb Space Telescope, orange stripes appear in the north and south polar regions, and bright tan stripes appear at the equator. The north and south poles glow in a greenish gray. The rings show an ice-cold neon white. The Saturnian moons Janus, Dione, and Enceladus are also visible. In the wider field image, Titan, Saturn's largest moon, appears on the left, and on the right are Mimas and Tethys.
◇James Webb reveals an unstable atmospheric structure
The images taken by James Webb show the distinctive structure of Saturn's atmosphere in detail. First, a ribbon wave appearing as a wavy pattern is visible in the high latitudes of the northern hemisphere. NASA's Cassini spacecraft first captured this phenomenon after entering Saturn's orbit on July 1, 2004.
Below that, remnants of the "Great Springtime Storm" of 2011–2012 remain as small spots. This is a massive, explosive atmospheric vortex that occurs in Saturn's northern hemisphere during spring, so large and powerful that it can alter Saturn's overall atmospheric structure.
Earlier, the hexagon-shaped jet stream captured by NASA's Voyager spacecraft at Saturn's north pole in 1981 also appears with some corners faintly visible. Saturn's hexagonal jet stream is similar to Earth's counterpart, but it is much larger and more stable in structure because it persists over decades. As the north pole of Saturn enters winter, it will be shrouded in darkness for the next 15 years. The hexagonal jet stream captured by James Webb will not be observable in high resolution until the 2040s.
Saturn's gray-green polar regions show that light at a wavelength of 4.3 µm (micrometers, one-millionth of a meter), corresponding to the mid-infrared, is being emitted. It may be that aerosols (fine particles) in the high-altitude atmosphere scattered the light, or it could be a sign of auroral activity caused by charged particles rubbing against the atmospheric magnetic field. The two space telescopes have already observed Saturn's auroras.
◇Hubble still active in its 37th year
In the Hubble Space Telescope's visible-light image, Saturn's horizontal bands appear pale yellow. Some bands at the north and south poles show a light bluish tint. The rings look bright gray, with less brightness than in James Webb's infrared image. The Hubble image shows the Saturnian moons Janus, Mimas, and Epimetheus.
The Hubble Space Telescope was jointly developed by the United States and the European Space Agency. It is a 13-meter cylindrical structure with a 2.4-meter primary mirror and weighs more than 12 tons. It was launched aboard NASA's space shuttle Discovery on Apr. 24, 1990. Although its original design life was 15 years, it is still observing space while orbiting in low Earth orbit about 540 kilometers up.
That is because the Hubble telescope is the only telescope designed to be serviced in space by astronauts. To date, space shuttles have traveled to the Hubble Space Telescope five times to repair the telescope and upgrade its performance, replacing and improving systems.
The James Webb Space Telescope is the largest space telescope ever built, developed by the United States, Europe, and Canada over 25 years at a cost of 13 trillion won. Along with a 6.5-meter primary mirror, it has a sunshield the size of a tennis court to block sunlight. It was launched into space on Christmas 2021 aboard an Ariane 5 rocket and arrived the following January at its observation point 1.5 million kilometers from Earth. James Webb is the largest space observatory to date. It can collect more than six times as much light as the Hubble telescope.
References
NASA (2026), https://science.nasa.gov/missions/webb/nasa-webb-hubble-share-most-comprehensive-view-of-saturn-to-date/
ESA (2026), https://www.esa.int/Science_Exploration/Space_Science/Webb/Webb_Hubble_capture_new_views_of_Saturn