Peculiar Galaxies of Arp 273

Explanation: The spiky stars in the foreground of this backyard telescopic frame are well within our own Milky Way Galaxy. But the two eye-catching galaxies lie far beyond the Milky Way, at a distance of over 300 million light-years. Their distorted appearance is due to gravitational tides as the pair engage in close encounters. Cataloged as Arp 273 (also as UGC 1810), the galaxies do look peculiar, but interacting galaxies are now understood to be common in the universe. Nearby, the large spiral Andromeda Galaxy is known to be some 2 million light-years away and approaching the Milky Way. The peculiar galaxies of Arp 273 may offer an analog of their far future encounter. Repeated galaxy encounters on a cosmic timescale can ultimately result in a merger into a single galaxy of stars. From our perspective, the bright cores of the Arp 273 galaxies are separated by only a little over 100,000 light-years.

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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.