A hundred and eighty degrees, eight degrees of orb
The opposition is the two bodies half a circle apart, and this site allows eight degrees either side. Because Uranus advances only about four minutes of arc a day and the Moon covers thirteen degrees, the Moon sweeps the whole sixteen degree window in a little over twenty four hours, once per lunar month.
That puts the frequency near one birth in twenty two, the same as the conjunction. The two aspects are equally common and are the two Moon to Uranus contacts that occur once rather than twice per circuit.
An opposition also means the two bodies are almost always in opposing signs and, if the birth time is known, in opposing houses. That geometry is the whole content of the aspect. Nothing is fused, nothing is hidden, and both ends are lit at once. This is the configuration that produces a full moon when the Sun is involved, and although Uranus is not the Sun, the same across-the-chart shape applies.
The pairing and what facing does to it
The Moon signifies the automatic level of a person: needs, moods, security, the domestic arrangements that let someone rest. Uranus signifies the break in a pattern, the thing that arrives without being scheduled and does not fit the existing arrangement.
Opposition is read as dialogue rather than friction. A square forces the issue through discomfort. An opposition instead makes the two visible to each other, and the classic outcome is oscillation: long stretches of wanting stability, punctuated by a decisive break with it, then a period of rebuilding.
Astrologers frequently read oppositions through other people, because whatever sits opposite tends to arrive in the form of somebody else. In this pairing that shows up as the person who keeps ending up in relationships or households with someone unpredictable, and who has to work out how much of that is a preference and how much is a projection of their own restlessness. That is an interpretive claim, not an astronomical one, and it is worth holding lightly.
Orb, houses and the axis it lands on
The axis matters more here than in any other Moon to Uranus contact, because an opposition always occupies two houses at once. A fourth to tenth version reads as home against public role. A first to seventh version reads as self against partner and is the one most often written up. A second to eighth version reads through money and dependence. None of those is automatic, but the axis is the first thing to check.
Orb behaves as usual. Inside three degrees the oscillation is a real feature. Past six it is faint, and a wide opposition across a sign boundary, where the Moon is at one degree of a sign and Uranus at twenty six of the opposing one, has very little of the classic shape left.
Sign polarity adds texture. Cancer and Capricorn, or Taurus and Scorpio, give an opposition between two signs that both dislike being moved, which sharpens the conflict. Gemini and Sagittarius give one where movement is already assumed, and the aspect quietens.
How much weight to give it
Because the Moon is fast, this is a personal aspect and the birth date narrows it to a day. That makes it worth reading properly, unlike the outer planet to outer planet contacts everybody born in a given decade shares.
Even so, one opposition is one line in a chart. If the rest of your chart is mobile and changeable, this simply agrees with it. If the rest is slow and fixed, the opposition is where the pressure shows, and that contrast is usually the more accurate reading than anything the aspect says on its own.
Uranus retrograde is not a factor. It is retrograde for something close to five months a year, which makes a natal retrograde Uranus completely ordinary, and it does not alter the geometry of the opposition in any way you would notice. The widget above gives you the orb, the two signs and the two houses, which is where the specific reading actually comes from.
Questions people ask about this
What does Moon opposite Uranus mean in a natal chart?
It means the Moon sits close to a hundred and eighty degrees from Uranus. The tradition reads this as an ongoing dialogue between the need for a settled routine and a pull towards breaking it, played out across two opposing houses.
How wide is the orb for this opposition?
Eight degrees on this site, the same as a conjunction. Because the Moon travels about thirteen degrees a day, the full sixteen degree window opens and closes inside roughly twenty six hours.
Does this aspect affect relationships?
Astrologers often read oppositions through other people, so this one is commonly interpreted through partners and household. That is an interpretation rather than a measurement, and it holds up best when the opposition falls on the first and seventh houses.
Is Moon opposite Uranus worse than the square?
No. Traditional sources describe the square as friction that forces action and the opposition as tension held in view. Neither is graded as worse, and the sign, house and orb decide which one reads more strongly in a given chart.
Why does my birth time change the result?
It does not usually change whether the aspect exists, since that is settled within the day. It changes the houses, and the Moon moves through a house every two hours or so, which is where most of the specific reading comes from.
Is this a rare aspect?
Not particularly. It occurs once in every lunar circuit for a window of about a day, which works out near one birth in twenty two. Frequency says nothing about how strongly it reads in a given chart.