How do I know when the Moon is void of course? Here’s how to figure it out from a chart. Follow along as we figure out what the Moon is doing this morning. (This is for Jennifer and for anyone not used to spotting aspects in the chart.)

Here’s a chart for 7:00 am EDT today, April 19, 2008, where I am in Arlington, Massachusetts, USA. (Click on the chart to enlarge it.)

First, let’s see where the Moon is. In this chart, it is at 18 Libra 52, in the 6th house. (Side note: if this were a horary chart you were analyzing, you would instantly make a note that Moon has entered the Via Combusta, the range from 15 Libra to 15 Scorpio, a stressful place for the Moon to be. It may or may not be relevant to your judgment, but you’d notice it.)

Next, let’s see where everybody else is so we can see who the Moon has already aspected and who it’s about to aspect, if anyone. Sometimes it helps to list the other planets in order by degree. (And, a reminder, I’m using just the classical planets here, not the outers.) So here they are by degree order, just counting up from 0 to 29:

• Saturn: 1 Virgo 50 Rx
• Mercury: 3 Taurus 21
• Venus: 16 Aries 18
• MOON: 18 Libra 52, as we said
• Mars: 19 Cancer 27
• Jupiter: 21 Capricorn 44
• Sun: 29 Aries 45

So, wind back the Moon to the point when it entered Libra, the sign where it is now, and then mentally move it forward through Libra. Who has the Moon already aspected? (Use just the Ptolemaic aspects: conjunction, sextile, square, trine, opposition.)

• Saturn? No. Virgo and Libra, being one sign apart, do not form any aspect. (That’s right, no semi-sextiles.)
• Mercury? No. Taurus and Libra, being five signs apart, do not form any aspect. (No quincunxes, either.)
• Venus? Yes! Aries and Libra are in opposition. Moon at 18 Libra has just separated from opposition to Venus at 16 Aries.

Do you see where we are? We’ve mentally taken Moon from 0 Libra to its current location at 18 Libra, and it’s only made one aspect so far, the opposition to Venus.

Is the Moon void of course yet? Let’s move it forward and see if it will make any other aspects before leaving Libra. To be void of course, it must have no further meetings on its schedule, so to speak.

• Will Moon aspect Mars at 19 Cancer? Yes! Mars is in Cancer, and Libra squares Cancer. Moon at 18 Libra is applying immediately to square Mars.
• Will Moon aspect Jupiter at 21 Capricorn? Yes! After separating from Mars, Moon applies to square Jupiter.
• Will Moon aspect Sun at 29 Aries? It should, shouldn’t it? Aries is opposite Libra. Aha, trick question! Let’s look at that a moment.

To know whether an aspect will be perfected (that is, completed), you need to know how fast each planet is moving. Not to the minute of arc, necessarily, but you need to have a general sense of how they behave. (Having an ephemeris you can consult also helps.)

The Moon moves the fastest of any planet. It covers about 13 degrees of arc per day, sometimes more, sometimes less. The Sun moves just under a degree of arc per day. So in most cases, the Moon is able to catch up to whatever planet it’s trying to aspect.

In this case, however, Moon at 18 Libra 52 would have to travel a good 11 degrees (plus a little more) to catch up with Sun. That’s almost a day’s travel for the Moon. And Sun, at 29 Aries 46, is within spitting distance of Taurus. With about 1/4 of a degree to travel to reach Taurus, and an average speed of just under a degree per day, Sun will get there in 1/4 of a day’s time. The Moon cannot catch up to the Sun before the Sun changes sign! (An aspect that is prevented due to one planet’s changing sign is called “frustration.”)

So, Moon is NOT yet void of course in this chart. However, it WILL be after it has perfected the square to Jupiter. The Jupiter square is its last aspect while in Libra. At that point, it will have a bit more than 8 degrees to travel, void of course, before reaching Scorpio’s frontier.

To know what time Moon will be void of course, you could do a number of things. You can click forward in your chart-casting software until Moon has passed the Jupiter square and see where that brings you. You could get an approximate time by figuring on just under 2 hours for every degree Moon has to travel – so, in this case, with 3 degrees between Moon and Jupiter, you could figure Moon will be VOC in about 6 hours. You could do all the lovely astrological math and time it yourself. Or you could just check an astrological calendar as I mentioned yesterday – though they might be including other planets and aspects which you may or may not wish to include.

Guess who IS void of course in this chart? That’s right, the Sun. Since it is at 29 Aries 46 and is not making any more aspects before changing sign, Sun is void of course in the chart above, and will be until it enters Taurus later today.