Some astrologers won’t use an orb larger than 5-6 degrees for major aspects in natal astrology, while others will be more generous and use an orb of 8 degrees. Astrologer Liz Greene uses a 10-degree orb for all major aspects and a 6-degree orb for the sextile in her calculations. This degree system is also used by her for the transiting planets and the aspects they make. Sometimes, if a conjunction or opposition in a person’s chart appears to be particularly potent, I’ll even shift it to 12 degrees, but Reinhold Ebertin says that you need to drastically shrink the orb of the aspects if you want to get good results from them.
In regards to the planetary orbs in transit, Jeff Green had this to say:
I use 5 degrees for transits. Prior to the actual aspect to a planet, or to the exact crossing of a house cusp or angle, one is given the opportunity to prepare for the issues that will be occurring. These opportunities are associated with premonitions and or “forebodings” about the “things to come.” Externally signs or events of what is to come can manifest themselves on a very tentative basis…Of course, many individuals dismiss these signs, pay no attention to them, or are simply confused as to their significance and meaning. For those who have been travelling the path of realization the capacity to understand and interpret these events and signs can help them prepare for what is to come. At minimum these events and signs will catch their attention and they will attempt to understand what they portend for the future. Thus, some kind of preparation will occur. Jeff Green
Tight Astrological Orbs
In all honesty, I don’t see the point in some astrologers limiting the orb of a transiting planet to just one degree. The standard astrological reading of applying and separating natal aspects is around 8 degrees, so why do astrologers use such a narrow orb for transits? Why not apply the same reasoning to transits if it is said that the energy of a natal aspect is felt when it is 8 degrees wide?
When dealing with fast-moving planets, I frequently use a smaller degree because there isn’t much time to prepare for a “minor” event because the planets are moving too quickly for anything to be really noticed during the buildup period. We use a wider orb for the transits of Jupiter, Saturn, Uranus, Neptune, and Pluto, as these planets are associated with more momentous occasions in life. Neptune and Pluto are the two planets with the slowest orbital periods, and their influence can be felt on a person in a wide range of ways.
Astrological Patterns says,
Many astrologers use wider orbs; they allow up to 14 degrees for aspects involving the Sun or moon, and 10 degrees for planets in aspect to each other. In the authors combined experience of eighty-four years in counseling and teaching, they have observed subtle leanings with these wide orbs; however, they are not overtly active or expressed in the life. The more exact the aspect, the stronger will be the expression of that which is promised in the aspect.
Liz Greene says,
The wider the orb the greater the flexibility and room to maneuver. So you feel the aspect at 10 degrees, but it will be much more intense if the aspect is within a couple of degrees.