Now is a good time to look for the seventh planet, Uranus. It is about as bright as it ever gets, and it is near a celestial landmark, the Pleiades, which makes it relatively easy to find.
Uranus was discovered to be a planet by the English astronomer William Herschel in 1781. He gave it the name "Georgium Sidus". It wasn't until 1850 that its present name, Uranus, became universally accepted.
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The Pleiades (left) and Uranus (white circle). Olympus E-M5iii + Sigma 56mm f/1.4 + softon filter. ISO 800, 15 s at f/2.8.
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Uranus was easily visible in 6x30 binoculars, but not with a 1.8x40 wide-field binocular. City lights and the quarter moon were too much for the low-power instrument to overcome.
The new "filter" that was tried was the Omegon cross-star plate for the Seestar S50. It consists of two crossed wires. The effect mimics the diffraction pattern created by the typical four-vaned secondary-mirror support of Newtonian and Cassegrain-type reflectors.
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The Pleiades with the Omegon cross-star filter.
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Hoya Softon-A filter.
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No filter.
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Omegon cross-star filter.
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Aldebaran and the Hyades cluster. Cross-star filter.
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Softon filter.
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The sky brightness was not measured for this session. The quarter-moon was still high in the sky and there appeared to be a thin cloud layer.
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