Hunting the Ice Giants

With the inner planets now gracing the morning rather than the early evening skies & Jupiter setting early in the evening, it is the ideal time to go hunting for slow moving Uranus & Neptune in their cold dark outer orbits. The timing is good, especially for viewing Uranus, with its current position being close to the Zenith (overhead) mid evening, in the constellation of Aquarius (the water bearer) & with Neptune not far away in Capricornius (the sea goat).

Finding Uranus

Uranus at Magnitude +5.9 will be just visible to the sharp eyed observer under clear dark skies (avoid moonlit nights and city lights) Neptune at Magnitude +7.9 on the other hand is almost twice as dim and cannot be seen with the naked eye. A good pair of 10×50 binoculars will allow you to locate both of these planets, however a telescope will be needed to see any detail.

Uranus (at 3 billion kilometers away) is in a good position to be found, located as it currently is about ½ way between the stars Phi Aquari & Lambda Aquari. These stars are close to the meridian (the central part of the sky) in the early evening soon after twilight.

With a moderate sized telescope or greater (150mm or 6 inchs) you will be able to see the Blue dot that is Uranus. However you will need Approximately 150x magnification to see the small aquamarine disk of the planet & the same goes for Neptune.

Unlike Mars, Jupiter and Saturn, there are no surface or cloud features to be seen unless you have a very large telescope and the season is right for storm formation on Uranus or Neptune.

Finding Neptune

Neptune (at 4.5 billion kilometers away) is a little harder to find, but once you have located the fainter but none the less distinctive triangle of Capricornius, locate the bright star (Magnitude 4.5) Iota Capricorni. Approximately 2 degrees (2 finger widths) away from this star and outside of the Triangle you will see the small deep blue disk of Neptune.

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