Author Archives: Chompsky

Behold: the centre of the Milky Way galaxy – 26,000 light years from us toward the constellation of Sagittarius, glowing with every type of light we can see, and a few we can’t. To wit:

In the featured image, high-energy X-ray emission captured by NASA’s orbiting Chandra X-Ray Observatory appears in green and blue, while low-energy radio emission captured by SARAO‘s ground-based MeerKAT telescope array is coloured red. Just on the right of the colourful central region lies Sagittarius A (Sag A), a strong radio source that coincides with Sag A*, our Galaxy’s central supermassive black hole. Hot gas surrounds Sag A, as well as a series of parallel radio filaments known as the Arc, seen just left of the image center. Numerous unusual single radio filaments are visible around the image. Many stars orbit in and around Sag A, as well as numerous small black holes and dense stellar cores known as neutron stars and white dwarfs. The Milky Way’s central supermassive black hole is currently being imaged by the Event Horizon Telescope.

(Image: X-Ray: NASA, CXC, UMass, D. Wang et al.; Radio: NRF, SARAO, MeerKAT)

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Behold: an only slightly exaggerated view of what one would see if hovering close to the ringed gas giant. To wit:

The image was taken in 2005 by the robot Cassini spacecraft that orbited Saturn from 2004 to 2017. Here Saturn’s majestic rings appear directly only as a curved line, appearing brown, in part, from its infrared glow. The rings best show their complex structure in the dark shadows they create across the upper part of the planet. The northern hemisphere of Saturn can appear partly blue for the same reason that Earth’s skies can appear blue — molecules in the cloudless portions of both planet’s atmospheres are better at scattering blue light than red. When looking deep into Saturn’s clouds, however, the natural gold hue of Saturn’s clouds becomes dominant. It is not known why southern Saturn does not show the same blue hue — one hypothesis holds that clouds are higher there. It is also not known why some of Saturn’s clouds are coloured gold.

(Image: NASA, ESA, JPL, ISS, Cassini Imaging Team; Processing & License: Judy Schmidt)

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