Jupiter, Saturn, Moon. amd Time

As Jupiter continues to catch up with Saturn, the Moon comes by, this time passing 2.2° south of Jupiter on June 8 and 2.7° south of Saturn on June 9.

See the end note about enlarging illustrations.

Those angular separations refer to the center of the Moon; from our northern latitudes, the Moon is pushed a bit south.

In my picture, the Moon (at twice its real size) is where it is seen from the chosen U.S. location; but the arrows connecting Moon positions are along the track it would take if viewed from the center of the Earth.  The difference is the effect called parallax.  (When you hold a finger in front of your nose, but look into the distance, you see two fingers, separated by parallax.)

The grouping of the three luminaries will be tightest at 22h Universal Time – 17 hours after the time of the picture and in daylight for America.  The planets and the Moon’s center get to be within a circle of diameter 5.06°, though that is as seen from Earth’s center; parallax makes it a bit wider.

For Saturn we show its disk, exaggerated 150 times in size, so as to show the current attitude of its rings (north face open toward us).

The Moon is two days past Full, so the planets will be twinkles within its glare.  (The magnitudes of Moon, Jupiter, and Saturn are -12, -3, and 0.

As the night goes on, the scene will slant up to higher in the sky.  (And then, if the sky is clear, the Milky Way will become visible.  But not Pluto!)

The “solstice point.” where the Sun is at mid winter, is the most southerly point on the ecliptic.  These planets, and the Moon when opposite to the summer Sun, are nearly as far south as they can be in the sky.

The “anti-Sun,” as I call it, is also not something that can be seen, except at a lunar eclipse, when Earth’s Shadow becomes visible on the Moon; but it is an interesting point to contemplate.  When at or near it, the Moon is Full and a planet is at opposition.  It divides the evening sky, to the right of it, from the morning sky, to the left.  By staying up late, you get a look into the morning sky, of which Jupiter and Saturn are the heralds.

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Times When Time Stood Still Department

The Sun stood still over Gibeon, and the Moon over the Valley of Aijalon, so that the Israelites could continue slaughtering their Amorite enemies (according to the Book of Joshua, chapter 10).

Zeus, impersonating the king of Mycenae who had to be away in a war, lay with his bride Alcmene for a night which he extended to the length of three, in order to generate the hero he had in mind: Hercules.

In Jorge Luis Borges’s story “The Secret Miracle,” Jaromir Hladík is facing a Nazi firing squad because he is Jewish.  He wishes he could complete the verse drama he was writing.  So time stands still for a year to let him do so.  He can do it in his head because verse is easier to memorize than prose.  When he fits the last word in, time resumes and the bullets that were in the air hit him.

Andrew Marvell’s poem “To His Coy Mistress.” in which he exhorts her not to wait centuries before accepting his love, ends:

Thus, though we cannot make our sun
Stand still, yet we will make him run!

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ILLUSTRATIONS in these posts are made with precision but have to be inserted in another format.  You may be able to enlarge them on your monitor.  One way: right-click, and choose “View image”, then enlarge.  Or choose “Copy image”, then put it on your desktop, then open it.  On an iPad or phone, use the finger gesture that enlarges (spreading with two fingers, or tapping and dragging with three fingers).  Other methods have been suggested, such as dragging the image to the desktop and opening it in other ways.

Sometimes I make improvements or corrections to a post after positing it.  If you click on the title, rather than on ‘Read more’, I think you are sure to see the latest version.

This weblog maintains its right to be about astronomy or anything under the sun.