Event Date: August 25th
Time: 3:14(.16) AM
Brief
After spending the last two evenings talking about Neptune, I will hop forward towards the Sun by roughly a billion miles (give or take), and now talk about Uranus! In the constellation of Cetus, for limited time, this is normally the time of Uranus' revolution that we see it in Pisces. However, because of the planet's ecliptic latitude swinging it a bit south of our Sun's path, from our perspective Uranus is just barely within the boundary of the sea monster. There will be some back and forth on this over the next several months, as Uranus' retrograde-then-prograde motion has it cross the boundary a few times.
The image here shows Uranus at transit within the Cetus boundary lines, It comes back to Pisces late this year, via retrograde motion, then back to Cetus for about a month early next year via prograde motion. Notice when looking closely, how near Uranus is to the border, and how the unevenness of them can have us understand the back and forth irregularly.
Time: 3:14(.16) AM
Brief
After spending the last two evenings talking about Neptune, I will hop forward towards the Sun by roughly a billion miles (give or take), and now talk about Uranus! In the constellation of Cetus, for limited time, this is normally the time of Uranus' revolution that we see it in Pisces. However, because of the planet's ecliptic latitude swinging it a bit south of our Sun's path, from our perspective Uranus is just barely within the boundary of the sea monster. There will be some back and forth on this over the next several months, as Uranus' retrograde-then-prograde motion has it cross the boundary a few times.
The image here shows Uranus at transit within the Cetus boundary lines, It comes back to Pisces late this year, via retrograde motion, then back to Cetus for about a month early next year via prograde motion. Notice when looking closely, how near Uranus is to the border, and how the unevenness of them can have us understand the back and forth irregularly.
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| click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp. |
Detailed
At about 1.8 billion miles from the Sun, Uranus takes about 84 years to revolve. As a result of being so much further from the Sun than us, has a retrograde period of about 5 months. This is compared to only a little over 2 months for our nearest outer-neighbor, Mars, and a little more than Jupiter and Saturn; around the 4-month mark for each. For Uranus, which covers about 30º of sky every 7 years (equivalent to about one zodiacal sign for that duration), it gives many of us living long enough to see it make a complete revolution during our lifetime. Since most of us likely won't understand the planets' movements against the stars until we are between 10-20 years old, it means an even longer time to have to live to consciously track a full Uranus revolution. If you are one of those who remember exactly where Uranus was in the sky when you were a young age, via binoculars or a telescope, hopefully you have followed it ever year since, to really have a good perspective of what planets do. By knowing such, we also can know why they earn their name as "wandering stars"!
This second image shows Uranus with a star field of 1º, or about 50x in magnification. Just as the case with Neptune in Aquarius, Uranus has a dim star field in Cetus, with most of the sea monsters "brighter" stars further south and east (while many are not much brighter than Aquarius'.
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