Aurora Over White Dome Geyser

Sometimes heaven and Earth erupt. A few years ago, green and red auroras appeared near the horizon, and brilliant bands of red were visible high overhead. A bright Moon lit the foreground of the scene, while familiar stars could be seen far away. The mosaic was shot in the field of White Dome Geyser in the western USA. White Dome erupted just after midnight, spraying a stream of water and vaporizing many meters into the air. The geyser water is heated to steam and then rises through rock cracks to the surface. Half of the geysers in the park are located in the park. The eruptions of White Dome Geyser continue even after the storm subsided.

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Explanation: Many spiral galaxies have bars across their centers. Even our own Milky Way Galaxy is thought to have a modest central bar. Prominently barred spiral galaxy NGC 6217, featured here, was captured in spectacular detail in this image taken by the Advanced Camera for Surveys on the orbiting Hubble Space Telescope in 2009. Visible are dark filamentary dust lanes, young clusters of bright blue stars, red emission nebulas of glowing hydrogen gas, a long bar of stars across the center, and a bright active nucleus that likely houses a supermassive black hole. Light takes about 60 million years to reach us from NGC 6217, which spans about 30,000 light years across and can be found toward the constellation of the Little Bear (Ursa Minor).