Declinations, the other dimension of a planet's position in an astrology chart, represented an overlooked technique until astrologer Kt Boehrer books were published. She thoroughfully investigated this subject over many years, bringing to astrologers' awareness the extraordinary power and value of declinations. A high-quality website with many valuable articles on declination is Mandala.be.
Also known as "the declination lady", as she used to sign her
messages, she pointed out the importance of out of bounds planets and
developed astrological techniques such the declination conversion into
This technique simply considers that as the Sun moves both in
longitude and declination throughout a year, there is a symbolic
relationship between a declination degree and the Sun's position in
longitude when it has the respective declination. But there're two
moments during a year when the Sun has the same declination (named
antiscia or solstice points), so there're two longitudes corresponding
to a specific declination of the Sun. So, this is it: a planet's
position in declination has two equivalent longitudes, representing a
sort of reflection, a mirroring, a hidden connection.
It therefore allows correlating the two dimensions, declination and
longitude, offering a way to integrate declinations in the regular
astrology chart interpretation.
Whenever a planet's declination is higher than the maximum Sun
declination (23°27' North/South), whenever a planet is out-of-bounds,
the above mentioned technique cannot be applied anymore, so Kt Boehrer
figured out a trick for this situation: the planet's declination is
considered to have a mirror co-declination on the other side of the
23°27' threshold. Example: a declination of 23°30' has a codeclination
Declination calculation: http://www.astrologyweekly.com/declination/index.php