NASA. LARGE FORMAT. Exceptional composite science image show - Lot 277

Lot 277
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NASA. LARGE FORMAT. Exceptional composite science image show - Lot 277
NASA. LARGE FORMAT. Exceptional composite science image showing Saturn's Lyman-alpha bulge, a hydrogen emission that is a persistent and unexpected excess detected by three separate NASA missions, namely Voyager 1, Cassini and the Hubble Space Telescope between 1980 and 2017. A Hubble near-ultraviolet image, obtained in 2017 during Saturn's northern hemisphere summer, is used as a reference to sketch the planet's Lyman-alpha emission. The rings appear much darker than the planet's body, as they reflect much less ultraviolet sunlight. Above the rings and the dark equatorial region, the Lyman-alpha bulge appears as an extended latitudinal band (30 degrees) that is 30% brighter than the surrounding regions. A small portion of the southern hemisphere appears between the rings and the equatorial region, but is less luminous than the northern hemisphere. North of the bulge region (upper right part of the image), the brightness of the disk gradually decreases with latitude towards the bright aurora region, shown here for reference (not to scale). A dark spot inside the aurora region represents the imprint of the planet's axis of rotation. Icy ring particles raining down on the atmosphere at specific latitudes and seasonal effects are thought to cause atmospheric heating that causes hydrogen in the upper atmosphere to reflect more Lyman-alpha sunlight into the bulge region. 2017. Vintage chromogenic print. Legend on back label. 40.6 x 40.6 cm with margins.
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