Straight across, with eight degrees of tolerance
An opposition is half the circle. With an eight degree orb, anything between a hundred and seventy two and a hundred and eighty eight degrees qualifies. Pluto's two hundred and forty eight year orbit makes it a fixed marker over a human lifetime, so the Sun sweeps the sixteen degree band in around a fortnight, once a year.
Roughly four or five per cent of births carry it. Everyone born in that window shares the aspect and, because Pluto lingers in a sign for anything from twelve to thirty years, the sign axis is a generational feature rather than a personal one. Pluto's orbit is markedly elliptical, which is why the time it spends in a sign varies so widely rather than dividing the two hundred and forty eight years evenly.
The two ends of the axis
The Sun is deliberate purpose and the sense of being someone in particular. Pluto is the buried, the compulsive, the thing that does not respond to reasoning. Placed opposite, they occupy different signs and different houses, and neither can be folded into the other.
The reading that follows is usually about power arriving from outside: other people who cannot be persuaded, situations that will not yield, relationships that turn into contests. That is the standard description and it has a standard correction attached, which is that an opposition describes a polarity the person carries rather than something being done to them. Charts with this aspect tend to reward the effort of locating both ends.
Because the signs are opposite they share a mode, so a fixed opposition entrenches where a cardinal one keeps restarting the argument and a mutable one keeps changing its terms. The mode is often more informative than either individual sign, since the sign of Pluto is fixed for a generation and tells you almost nothing about the person in front of you.
The house axis, and why the birth time is not optional
The whole personal layer of this aspect is the pair of houses it falls across. Sun in the seventh opposing Pluto in the first reads as partnership against self-definition. Sun in the second opposing Pluto in the eighth reads as money, ownership and what is shared. Same aspect, different lives, and no way to tell which from the date alone.
Houses rotate about a degree every four minutes, so a birth time rounded to the hour can move the axis by a whole house. If the time is uncertain, say so and read the aspect only as far as the signs allow. A birth certificate is the best source. Family recollection is usually rounded, often to the nearest half hour, and that is enough to relocate the entire axis.
Orb, retrogrades and the case for saying less
Inside two degrees the opposition is a genuine structural feature. Between two and five it is one theme among several. Beyond five it flattens, and an opposition at seven degrees in a chart where Pluto is otherwise untouched is background. That is not a disappointing result, it is an accurate one.
Pluto is retrograde for close to half of every year, so a natal retrograde Pluto is unremarkable and is not evidence of anything. The features that actually raise the weight of this aspect are a tight orb, an angle involved, or a fast body making a close aspect to the same degrees.
The check above returns the exact separation, which is the number to weigh all of this against.
Questions people ask about this
What is Sun opposite Pluto read to mean?
Conscious purpose facing something that will not be negotiated with, held across the chart so both ends stay visible. It commonly shows up as tension with people or circumstances that cannot be persuaded, which the tradition treats as one end of the person's own axis.
How common is Sun opposite Pluto?
About four or five per cent of births. Pluto is effectively stationary over a human lifetime, so the Sun makes the aspect alone and stays in orb for roughly a fortnight each year.
Does this aspect mean power struggles?
That is the usual phrasing. It is worth treating carefully, since an opposition describes a polarity within the chart rather than a prediction about other people. The house axis tells you where the tradition expects it to appear.
Is Sun opposite Pluto worse than the square?
Neither is worse. The tradition reads the opposition as dialogue across the chart and the square as friction with no line of sight, so they describe different mechanics rather than different amounts of difficulty.
Do I need an exact birth time?
For the useful part, yes. The signs are shared with everyone born in the same stretch of years. The house axis is what individualises the aspect, and it shifts by a degree every four minutes.
Does a retrograde Pluto intensify it?
No. Pluto spends close to half of each year retrograde, so roughly half of all charts have it. It is the ordinary case and carries no weight of its own here.