What does “west” mean? It means the direction toward which Earth rolls. You can imagine it by rolling over leftward in bed. The wall you see is the westward sky.
The Moon (shown at 4 times its size) will pass just under a degree north of Spica, the brightest star of Virgo, at 4h Universal Time on July 14, which is 4 or more hours earlier by clocks on North American summer shifted time.
This refers to the center of the half-degree-wide Moon, as seen from the center of Earth. From northern latitudes, the Moon, because of its nearness, is parallax-displaced southward, so that it passes even closer to Spica and occults (hides) it as seen from most of North America.
And the Moon has reached first quarter phases, 90° west of the Sun. So it is crossing outward over our orbit behind us, as shown by the point marked “antapex of Earth’s way.”
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The wall you see is actually West after rolling in bed ONLY if your head was towards the south. This true whether someone is in the northern hemisphere or the southern.
I am unclear on what does “west” mean; surely we are both rotating and revolving to the east. Everyone sees the sun “rise”, and new constellations throughout the year appear in the east. Depending on which way we are facing (up to the sky, or down into the earth), and the directions the tops of our heads are pointing (north or south) when we roll to our left, our views can change: for instance, MY leftward roll shows me the eastern sky. No doubt there is a fault in my understanding.
Sounds like a metaphor for current politics
Hello Guy,
The second sentence might be recast by substituting the preposition “from” for “toward” and, in the fourth sentence, by substituting “behind you” for “you see”.
My sense is that Earth rolls eastward. The head of my bed points north. When I roll to the left, I’m facing the eastern wall of my bedroom, and the windows through which I see the Sun and Moon rise over my eastern horizon.
If the sky is clear this afternoon I will try to see the Moon occult Spica through mounted 15×70 binoculars. The Moon’s dark limb will cover Spica in late afternoon here, and Spica will emerge from behind the bright limb a few minutes after sunset. I doubt I’ll see Spica, but I have a greater chance if I look than if I don’t.
a question, please. Tarius? in the banner. thank You for your work that helps me understand a number of things!
By “the banner” do you mean the image that appears across the top of the blog post? These images are placed there randomly by the sysem, so I don’t know which of them appears for you on a given occasion, and don’t know which of them contained “Tarius”. Could you describe that banner image, if you remember it?
The Earth rotates from west to east so seems like it is “rolling” east.
Sorry, but to me the Earth turns on its axis towards the East, as the stars appear to drift towards the West. Can you explain ?