A Jovian Superfecta

Earlier this month I was hoping to get in another imaging session for the current Jupiter apparition, with the planet still standing relatively high as the May twilight deepened. I started in “White Light” (color) and quickly saw that the Great Red Spot (GRS) was rising and so I’d have it well positioned. The seeing however, was definitely sub-par, probably a 3 (maybe a 2?) out of 10.

Yet even under this mediocre seeing, it occurred to me that this was an opportunity to try for a wavelength superfecta, capturing the planet and its iconic storm in four different lights: WL, Infrared (IR), Methane (CH4) (UV), and Ultraviolet. It was a little challenging due to the low transmission I get in the CH4 and UV bands, causing the frames-per-second to drop dramatically. In such situations I leverage 2×2 binning, which groups four pixels into one. That makes the target effectively brighter, boosting the signal through this very dark filter. But it also reduces the image scale, so Jupiter appears slightly smaller and less detailed than in my unbinned captures.

The result was an interesting mosaic showcasing how Jupiter presents a different and scientifically valuable appearance in these varying bands of light. Each wavelength highlights a different altitude, particle size, or scattering process in the Jovian atmosphere. The GRS, being a deep, long‑lived anticyclone with complex vertical structure, becomes a perfect case study.

White Light

White light is the “baseline Jupiter”, the view closest to what the eye sees. It is a blend of scattering from cloud tops and deeper layers. The GRS’s color comes from chromophores (complex molecules produced by photochemistry) concentrated in its upper haze.

• The GRS appears as a salmon‑colored oval embedded in the South Equatorial Belt.
• Contrast is moderate because white light integrates photons from many atmospheric layers.

Ultraviolet (UV)

UV images emphasize high‑altitude hazes and aerosols. UV absorption is dominated by photochemical hazes. The GRS has a thick, vertically extended haze cap that blocks UV, making it stand out as a dark feature.

• The GRS typically appears dark in UV because its upper haze absorbs strongly at short wavelengths.
• Surrounding high-altitude haze regions appear bright.
• The UV view often looks “sharper” because it isolates the uppermost layers.

Infrared

Near‑IR wavelengths penetrate deeper into the cloud deck. IR brightness correlates with cloud-top altitude and temperature. The GRS’s anticyclonic upwelling lifts ammonia clouds to higher, colder levels, making it a strong IR reflector.

• The GRS often appears bright in IR because its cloud tops are higher and colder than surrounding regions.
• Belts and zones invert their contrast relative to visible light.
• Even though seeing is often steadier in IR, on this particular night it was not a huge help with poor conditions.

Methane Band

The methane absorption band is the most altitude‑selective of the four. Methane imaging isolates the highest cloud layers, with low-altitude features vanishing almost completely. The GRS’s brightness confirms its vertical extent and the strong upwelling at its center.

• Bright areas in CH₄ indicate very high-altitude clouds that reflect sunlight before it can be absorbed by methane.
• The GRS is usually bright in methane band because its cloud tops extend high into the upper troposphere.
• If you look closely you can also make out tiny NN-LRS-1 near the same longitude of the GRS but in the Northern Polar Region of the planet.

The GRS changes appearance because each wavelength samples a different combination of scattering, absorption, and cloud height. The storm’s vertical structure is complex: a tall central canopy, deep roots, and a surrounding turbulent wake. Multi‑wavelength imaging is one of the few ways amateurs can probe that structure directly.

If you’ve never tried imaging Jupiter beyond one-shot color, you may want to consider expanding your armamentarium to include some additional filters. I’d start off with an IR as it is the easiest and also has the advantage of being a mild antidote to poor seeing. Later on adding a simple UV or methane filter can expand your imaging opportunities of the planet and provide additional valuable scientific information. Jupiter rewards curiosity – and it rewards imagers who look at it in more than one light.