A birth chart is flat. It is a circle, and it records one thing about each planet: how far around the zodiac it stands. That is its longitude, and almost everything in ordinary astrology is built from it, the signs, the houses and the aspects alike.

But the sky is not flat. Through the year the Sun climbs north of the celestial equator, the Earth's equator projected onto the sky, and then sinks south of it again. The planets do the same. How far north or south of that line a planet stands is its declination, measured in degrees north or south. It is a whole second dimension of the chart, and the wheel leaves it out entirely.

Most of the time that does not matter much, because declination follows longitude fairly closely. But not always, and the places where it adds something are exactly the places where an ordinary reading of a chart feels as if something is missing.

Parallels and contraparallels

Two planets at the same declination are in contact, whatever their signs say. There are two kinds of contact.

When the two are on the same side of the equator, both north or both south, at the same declination, they are parallel. A parallel is read like a conjunction: the two planets blend and act together.

When one is as far north as the other is south, they are contraparallel. A contraparallel is read like an opposition: the two planets face each other, pull in two directions, and have to be balanced.

Here is why this matters. Imagine a chart with Mars at 10° Leo and Jupiter at 20° Taurus. They are 80 degrees apart, which is no aspect at all, and an ordinary reading would treat them as strangers. But both stand at almost the same declination north of the equator, a little under 18 degrees. They are parallel. If the person in question goes after things with an unusual mixture of force and generosity, or takes on far more than anyone thought sensible and seems to enjoy it, this is where it comes from. The longitudes never mentioned it.

Our report lists every parallel and contraparallel between the planets within one degree of declination, the tightest first.

Out of bounds

The second thing declination shows is more striking still. The Sun never goes further north or south than about 23°26', which is the tilt of the Earth's axis. That limit is called the obliquity of the ecliptic, and it changes very slowly over the centuries.

The Moon and the planets do not keep to that limit. Because their paths are tilted slightly against the Sun's, they sometimes go further north or south than the Sun ever does. A planet beyond the Sun's limit is out of bounds.

Astrologers read an out-of-bounds planet as operating outside the usual rules. Not stronger, exactly, but less governed: original, unpredictable, hard to fit into the expected shape. An out-of-bounds Mercury might belong to someone who thinks along routes nobody else takes and arrives at the right answer by a path they cannot explain. An out-of-bounds Mars might act first and consult the plan afterwards, sometimes to everyone's surprise including their own.

The planet that goes out of bounds most often is the Moon, and an out-of-bounds Moon in a birth chart is one of the most noticeable things this technique can show. Emotions run outside the expected range. Such a person may feel things more intensely than the people around them, or in a way those people do not recognise, and may spend years being told they are "too much" before discovering it is simply how they are built. Mars, Mercury and Venus go out of bounds less often.

Our report measures each planet against the Sun's limit for the date of your birth, not a rounded modern figure, and says how far past the limit any out-of-bounds planet stands.

Antiscia: the same idea in longitude

The old astrologers had a way of seeing declination contacts without measuring declination. Mirror a planet across the axis from 0° Cancer to 0° Capricorn, the points where the Sun turns at the solstices, and you land on its antiscion: the degree that shares its declination. In the example above, 10° Leo and 20° Taurus are mirror images across that axis, which is why Mars and Jupiter turned out to be parallel.

Mirror a planet across the other axis, 0° Aries to 0° Libra, and you land on its contra-antiscion. Our report gives each planet's antiscion and lists any planet sitting within a degree of another planet's mirror.

What the report shows

The report covers the Sun, the Moon and the planets out to Pluto. It gives each one's declination, north or south, and marks those out of bounds. It lists the parallels and contraparallels, then the antiscia. And it draws the chart in its second dimension: a graph with south on the left and north on the right, where every planet hangs at its own declination. Planets stacked in one column are parallel, a dotted arc beneath joins a contraparallel across the equator, and the shaded ends lie past the Sun's limit.

How to read declinations

Read declinations as a second opinion, not a replacement for the birth chart. They confirm, complicate or quietly explain what the longitudes have already said. Start with the tightest parallel or contraparallel and ask what those two planets do together. Then look for any out-of-bounds planet, and read it as the part of the person that refuses the usual limits. Use the antiscia where they add something the parallels have not already said.

The most valuable moment for this technique is when two planets in a chart obviously work together and there is no aspect between them. It is usually a parallel. Astrologers who find one for the first time often feel the way people do when they find their glasses on their own head.

Birth time

Declinations need less of a birth time than most techniques. The planets' declinations change slowly through a day, so they hold even with an uncertain hour. The Moon's changes fastest, by up to five degrees in a day. When the birth time is unknown, our report casts the chart for noon and marks the Moon as approximate.

To see the dimension your wheel leaves out, open your declinations here, start with the parallels, and check whether any planet in your chart is running out of bounds.

Frequently asked questions

What is declination in astrology?
How far north or south of the celestial equator a planet stands, measured in degrees. It is the dimension an ordinary chart leaves out, since the chart records only position around the zodiac.

What is a parallel?
Two planets at the same declination on the same side of the equator. It works like a conjunction, and it can join planets that make no aspect at all by longitude. On opposite sides it is a contraparallel, read like an opposition.

What does out of bounds mean?
That a planet has gone beyond the Sun's own limit of about 23°26' of declination. Such a planet is read as acting outside the usual rules. The Moon does it most often.

What orb does the report use?
One degree, for parallels and contraparallels and for antiscia alike.

What are antiscia?
A planet's mirror across the axis of the solstices. A planet and its antiscion share a declination, so a planet sitting on another's antiscion is in a contact the ordinary aspects do not name.

Do I need my birth time?
Less than for most techniques. Without one the report casts the chart for noon: the planets hold, and only the Moon is marked approximate, since its declination can change by several degrees in a day.