Your birthday tells you the Sun was in Capricorn. It says much less about what that Sun does to the rest of your chart. One of its jobs is easy to measure, and almost no one prints it.
The Sun hides the planets that stand close to it. The old books call a planet that close combust, which means burned. I ran the sky from 1600 to 2400 and asked one plain question. In how many Capricorn births does the Sun burn Mercury, the planet of thought and speech? The answer is 28.2 percent. That is more than one Capricorn in four.
For a Gemini Sun, the same figure is 22.1 percent. So a Capricorn is about 28 percent more likely than a Gemini to be born with Mercury lost in the glare. Only Sagittarius and Scorpio, the two signs just before it, beat it. This page gives the count, the cause, the dates by birth year, and the method.
The sign itself has its own page. Our guide to the Capricorn sign covers the traits, the dates and why the Sun spends fewer days in Capricorn than in any other sign. Here the Sun is treated as a placement: a body in your chart that acts on its neighbors.
When the Sun enters Capricorn in the United States
Capricorn starts at the December solstice, and that is true by definition. Western astrology uses the tropical zodiac, which is tied to the seasons. In that zodiac, the first point of Capricorn is the spot where the Sun stands farthest south. So the solstice and the start of the sign are the same moment, to the second.
The clock date is not fixed, though. I timed each entry from 1900 to 2100 and read it on New York clocks.
| Date the Sun entered Capricorn, New York time | Number of years out of 201 | When it happens. |
|---|---|---|
| December 20 | 16 years | Only from 2052 on, first in leap years. |
| December 21 | 122 years | Each year from 2012 to 2051. |
| December 22 | 63 years | For the last time in 2011. |
The drift comes from the calendar, not the sky. The year 1900 skipped its leap day, so the date started late. Since then, the four year leap cycle runs a little long against the real solar year. That pulls the start of Capricorn earlier, bit by bit, until the year 2100 skips a leap day again.
The West Coast runs three hours behind, so its dates come earlier. In Los Angeles, the Sun entered Capricorn on December 20 in 26 of those years, December 21 in 128 years, and December 22 in 47 years.
Here are the next three entries, in New York time. On December 21, 2026, the Sun enters Capricorn at 3:50 pm. On December 21, 2027, it enters at 9:42 pm. On December 21, 2028, it enters at 3:19 am.
Born on December 21 or 22?
These two days cause most of the doubt, so I counted them minute by minute over the same 201 years, in New York time.
| Birth date in New York | Years the whole day was Capricorn | Years the whole day was Sagittarius | Years the Sun changed sign during the day. |
|---|---|---|---|
| December 21 | 16 years | 63 years | 122 years. |
| December 22 | 138 years | No year at all | 63 years. |
Across all those days, 35 percent of the minutes of December 21 fall in Capricorn. For December 22, it is 90 percent. So December 22 leans hard toward Capricorn, and December 21 leans the other way. In most years, only the hour of birth settles it. If your hour lands before the entry, you are a Sagittarius, and our page on the Sun in Sagittarius is the one to read.
What the Sun owns in Capricorn, and what it does not
The old writers gave each planet a score in each sign. They called it essential dignity: how much a planet is at home where it stands. Ptolemy set out the scheme in the Tetrabiblos, around 150 AD. William Lilly printed the full table in Christian Astrology in 1647. Our guide to planetary dignities and debilities explains each rank.
Here is how the Sun scores in Capricorn, one rank at a time.
| Rank in the old scheme | Who holds it in Capricorn | Does the Sun get it? |
|---|---|---|
| Domicile, the home sign | Saturn | No, the Sun is a guest here. |
| Exaltation, the seat of honor | Mars, peaking at 28 degrees | No. |
| Triplicity, the rule of the element | Venus by day and the Moon by night, for earth signs | No. |
| Terms, five small slices of the sign | Five planets share them | No, the Sun has no terms in any sign. |
| Face, one of three slices of ten degrees | Jupiter, then Mars, then the Sun | Yes, from 20 to 30 degrees. |
| Detriment or fall, the weak spots | Not the Sun here | Its weak signs are Aquarius and Libra. |
So the common line, that the Sun has no dignity in Capricorn, is almost right but not quite. In the first twenty degrees, the Sun holds nothing. Lilly’s word for that is peregrine, which means a wanderer. In the last ten degrees, it holds its own face, the smallest dignity on the list.
I measured how many Capricorns that covers. Of all the time the Sun spends in Capricorn, 33.3 percent falls in those last ten degrees. In most years, that means births from about January 10 to the end of the sign. So one Capricorn in three has a Sun with a small claim of its own. The other two are guests in Saturn’s house, with no rank at all.
The Sun burns what stands next to it
Now to the main count. The Sun is not one planet among the rest in the old texts. It is the king, and it hides what comes too close. The tradition sets three distances.
| Gap between the planet and the Sun | Name in the tradition | How the old texts read it. |
|---|---|---|
| Less than 17 minutes of arc | Cazimi, from the Arabic for in the heart | Seated in the king’s lap, and very strong. |
| From 17 minutes out to 8 degrees 30 minutes | Combust, which means burned | Hidden and weakened, its work lost in the glare. |
| From 8 degrees 30 minutes out to 17 degrees | Under the beams | Faint, out of sight in the twilight. |
A minute of arc is one sixtieth of a degree. Seventeen of them make about half the width of the full Moon. The limit of 8 degrees 30 minutes is the one Lilly uses. Our page on the conjunction in astrology found that about one chart in four holds a burned Mercury. My own count agrees: 25.0 percent across all Sun signs, cazimi included.
That is the mean. It is not the same for each Sun sign.
Capricorn season burns Mercury more than most
Here is the share of births with Mercury within 8 degrees 30 minutes of the Sun, for each Sun sign. It covers each moment from 1600 to 2400, and it counts cazimi and combust as one.
| Sun sign at birth | Share of births with Mercury combust or cazimi. |
|---|---|
| Sun in Sagittarius | 29.1 percent. |
| Sun in Scorpio | 28.4 percent. |
| Sun in Capricorn | 28.2 percent. |
| Sun in Libra | 26.6 percent. |
| Sun in Aquarius | 26.4 percent. |
| Sun in Virgo | 24.6 percent. |
| Sun in Pisces | 24.5 percent. |
| Sun in Aries | 23.2 percent. |
| Sun in Leo | 23.2 percent. |
| Sun in Cancer | 22.4 percent. |
| Sun in Taurus | 22.3 percent. |
| Sun in Gemini | 22.1 percent. |
The pattern is a wave across the year. It peaks with the Sun in Sagittarius, and it bottoms out with the Sun in Gemini. Capricorn sits near the top, just behind Sagittarius and Scorpio.
The wider zone tells the same story. With the Sun in Capricorn, Mercury sits within 17 degrees of it in 62.2 percent of births. With the Sun in Gemini, the figure is 49.0 percent. So most Capricorns are born with Mercury either burned or under the beams.
The rarest case follows the same wave. A Capricorn Sun has Mercury cazimi in 0.92 percent of births, or about one in 109. The mean over all signs is one in 123.
Why winter keeps Mercury in the glare
Mercury passes the Sun in two ways. In the first, it slips between the Earth and the Sun. It is then retrograde, which means it seems to move backward against the stars. That pass is quick. In the second, Mercury goes round behind the Sun, on the far side of its path. That pass is slow.
I timed each of those passes from 1600 to 2400 and noted the Sun sign at the moment of the meeting. When the meeting happens behind the Sun with the Sun in Capricorn, Mercury stays inside the burned zone for 28.2 days in the mean. When the same kind of meeting happens with the Sun in Gemini, it lasts 14.1 days. The quick pass in front of the Sun lasts about 7.5 days in Capricorn season.
So the far side pass in winter lasts twice as long as the one in June. The cause is the shape of Mercury’s path. It is the most stretched orbit of all the planets. Its distance from the Sun swings from 0.31 to 0.47 of the Earth’s own distance.
Where Mercury is on that path at the meeting decides the speed. In the Capricorn meetings, Mercury stood 0.45 of the Earth’s distance from the Sun, close to its far point. Out there, it moves at its slowest, so it lingers behind the Sun. In the Gemini meetings, it stood 0.31 away, at its near point, and it raced past. This is plain orbit mechanics. It does not depend on any reading of the chart.
Which sign your Mercury is in
Mercury never strays far from the Sun. Over the 800 years, the widest gap I found with a Capricorn Sun was 24.7 degrees. So Mercury can only be in Sagittarius, Capricorn or Aquarius. Here is the split for Capricorn Suns.
| Sign that Mercury is in | Share of Capricorn Suns. |
|---|---|
| Mercury in Capricorn | 56.8 percent. |
| Mercury in Sagittarius | 26.5 percent. |
| Mercury in Aquarius | 16.8 percent. |
These are the same figures our page on Mercury in Aquarius found over the same 800 years. My two routes gave them again, within a tenth of a point. If yours is in your own sign, our page on Mercury in Capricorn reads it in detail.
Why does Sagittarius beat Aquarius? In this season, Mercury sits behind the Sun in the zodiac more than in front of it. With the Sun in Capricorn, Mercury is on that side 56.0 percent of the time. On that side, it rises before the Sun as a morning star, and the sign behind Capricorn is Sagittarius.
One thing does not change with the season. Mercury is retrograde in 18.6 percent of Capricorn births. The figure for all births is 19.2 percent. So a backward Mercury is about as common here as anywhere else.
Venus is not squeezed the same way
Venus also stays close to the Sun, but its orbit is almost a circle. So the season should not matter much, and it does not. With the Sun in Capricorn, Venus sits within 8 degrees 30 minutes of it in 12.8 percent of births. The figure for all births is 13.1 percent.
About 23 Capricorn Suns in 100 also have Venus in Capricorn. The rest have Venus in Sagittarius, Aquarius, Scorpio or Pisces. Only Mercury gets pulled into the glare by winter.
Is your Mercury burned? The seasons from 1990 to 2027
The share swings hard from one birth year to the next. Some Capricorn seasons have no burned Mercury at all. Others have it almost the whole month. The table gives the span when Mercury was within 8 degrees 30 minutes of a Capricorn Sun, by New York date. On an edge day, the hour decides.
| Capricorn season | Dates when Mercury was burned | Share of the season. |
|---|---|---|
| Season of 1990 to 1991 | Dec 21 to Dec 27, 1990 | 20 percent. |
| Season of 1991 to 1992 | No dates | None this season. |
| Season of 1992 to 1993 | Jan 9 to Jan 19, 1993 | 35 percent. |
| Season of 1993 to 1994 | Dec 21, 1993 to Jan 16, 1994 | 89 percent. |
| Season of 1994 to 1995 | Dec 21 to Dec 28, 1994 | 23 percent. |
| Season of 1995 to 1996 | Jan 14 to Jan 20, 1996 | 20 percent. |
| Season of 1996 to 1997 | Dec 29, 1996 to Jan 5, 1997 | 25 percent. |
| Seasons of 1997 to 1999 | No dates | None in either season. |
| Season of 1999 to 2000 | Jan 1 to Jan 20, 2000 | 66 percent. |
| Season of 2000 to 2001 | Dec 21, 2000 to Jan 8, 2001 | 62 percent. |
| Season of 2001 to 2002 | No dates | None this season. |
| Season of 2002 to 2003 | Jan 7 to Jan 15, 2003 | 26 percent. |
| Season of 2003 to 2004 | Dec 23 to Dec 30, 2003 | 25 percent. |
| Season of 2004 to 2005 | No dates | None this season. |
| Season of 2005 to 2006 | Jan 12 to Jan 20, 2006 | 24 percent. |
| Season of 2006 to 2007 | Dec 22, 2006 to Jan 20, 2007 | 96 percent. |
| Season of 2007 to 2008 | Dec 22, 2007 to Jan 1, 2008 | 34 percent. |
| Season of 2008 to 2009 | Jan 16 to Jan 19, 2009 | 11 percent. |
| Season of 2009 to 2010 | Dec 31, 2009 to Jan 8, 2010 | 25 percent. |
| Season of 2010 to 2011 | Dec 21 to Dec 23, 2010 | 6 percent. |
| Season of 2011 to 2012 | No dates | None this season. |
| Season of 2012 to 2013 | Jan 3 to Jan 19, 2013 | 54 percent. |
| Season of 2013 to 2014 | Dec 21, 2013 to Jan 11, 2014 | 72 percent. |
| Season of 2014 to 2015 | Dec 21 to Dec 23, 2014 | 5 percent. |
| Season of 2015 to 2016 | Jan 10 to Jan 18, 2016 | 26 percent. |
| Season of 2016 to 2017 | Dec 24, 2016 to Jan 1, 2017 | 25 percent. |
| Season of 2017 to 2018 | No dates | None this season. |
| Season of 2018 to 2019 | Jan 16 to Jan 20, 2019 | 13 percent. |
| Season of 2019 to 2020 | Dec 26, 2019 to Jan 20, 2020 | 85 percent. |
| Season of 2020 to 2021 | Dec 21, 2020 to Jan 3, 2021 | 45 percent. |
| Season of 2021 to 2022 | Jan 19, 2022 only | 2 percent. |
| Season of 2022 to 2023 | Jan 3 to Jan 11, 2023 | 26 percent. |
| Season of 2023 to 2024 | Dec 21 to Dec 26, 2023 | 15 percent. |
| Season of 2024 to 2025 | No dates | None this season. |
| Season of 2025 to 2026 | Jan 7 to Jan 19, 2026 | 43 percent. |
| Season of 2026 to 2027 | Dec 21, 2026 to Jan 15, 2027 | 83 percent. |
The long runs are the far side passes. Most runs of about a week are the quick passes in front of the Sun, with Mercury retrograde. The short runs that touch December 21 or January 20 are the tail ends of a pass that began or ended in the next sign.
The coming season is one of the long ones. Mercury meets the Sun exactly at 12:09 pm New York time on January 1, 2027. A baby born in New York that day between 12:34 am and 11:42 pm will have Mercury cazimi, in the heart of the Sun.
How to check your own chart
Take the degree of your Sun and the degree of your Mercury from your birth chart. If both are in Capricorn, subtract one from the other. If Mercury is in Sagittarius, add the 30 degrees of the sign between them. Take Mercury at 25 degrees of Sagittarius and the Sun at 2 degrees of Capricorn. The gap is 5 plus 2, so 7 degrees. That Mercury is combust. Under 17 minutes of arc, it is cazimi. From 8 degrees 30 minutes to 17 degrees, it is under the beams.
What the tradition reads into a burned Mercury
These are readings from old texts and modern writers, not tested facts. Astrology is not a science. It is a symbolic language with a long written record.
Lilly treats a combust planet as badly placed. In his questions of daily life, it points to a person held in fear by someone more powerful. Vettius Valens, in his Anthologies, reads planets under the beams as hidden. Their work goes on out of public view. Chris Brennan, in Hellenistic Astrology, shows how the Greek authors cared about whether a planet could be seen in the sky at all. Demetra George makes the same point in Ancient Astrology in Theory and Practice.
Modern writers soften the verdict. Robert Hand, in Horoscope Symbols, reads Mercury close to the Sun as a mind fused with the will. The thinking and the self run as one, so it is hard to see your own ideas from the outside. Stephen Arroyo reads the Sun as the core of vital force. Liz Greene reads it as the path of the hero. With Mercury burned, the path and the thinking about it are one and the same.
Put that beside Capricorn, a sign ruled by Saturn and tied to career and long plans. A burned Mercury here reads as a mind that works for the plan and rarely steps back to argue with it. A Mercury out of the glare, in Sagittarius or Aquarius, reads as a mind with more room to disagree with its owner. The count on this page says the first kind is more common in Capricorn than in most signs.
The same placement reads differently by gender in everyday talk, which is why the portrait of the Capricorn woman needs its own numbers.
How I measured it
Each figure on this page comes from my own runs, and here is the method, so anyone can check it.
For the first route, I used the astronomy-engine library. An ephemeris is a table of where each body sits at a given moment, and this library computes one. I used the tropical zodiac and apparent positions from the Earth. I read the Sun, Mercury and Venus every 0.05 of a day, which is every 72 minutes, from 1600 to 2400. That is 5,843,884 moments at a fixed step, with no random draws. The gap between two bodies is the difference in their position along the zodiac.
For the second route, I used JPL Horizons, the NASA ephemeris service, with its DE441 model. I pulled one position per day for the Sun, Mercury and Venus over the same 800 years. That is 292,194 days. The two routes agree closely. For Capricorn, the burned Mercury share came out at 28.20 percent and 28.23 percent. For Gemini, both gave 22.11 percent. The Mercury sign split matched to within 0.03 points.
For the dates, I found each entry of the Sun into Capricorn by halving the time window until it was exact to the second. I checked seven years against JPL Horizons. Six agreed within 31 seconds. The year 2096 differed by two minutes, since no one can predict the spin of the Earth that far ahead to the second. New York dates use the real time zone rules, with the war time of 1942 to 1945.
For the passes behind and in front of the Sun, I stepped every 0.02 of a day and timed each span inside 8 degrees 30 minutes. One limit is worth saying. I gave each moment of the 800 years the same weight. Real births are not spread that way, and the share for one birth year can sit far from the mean, as the table of seasons shows.
Questions people ask about the Sun in Capricorn
Is the Sun strong or weak in Capricorn?
Neither, in the old scheme. Capricorn is Saturn’s house, and the Sun is a guest there. It has no domicile, exaltation or triplicity in the sign. In Lilly’s table, it holds only the last ten degrees as its face, which covers about one Capricorn in three. It is not in its detriment or fall either.
How common is a combust Mercury for a Capricorn Sun?
Mercury is within 8 degrees 30 minutes of the Sun in 28.2 percent of Capricorn births, across the years 1600 to 2400. That is more than one in four. For a Gemini Sun, the figure is 22.1 percent.
Can a Capricorn have Mercury in Aquarius?
Yes. It happens in 16.8 percent of Capricorn births. Mercury is in Capricorn for 56.8 percent and in Sagittarius for 26.5 percent. No other sign is possible, since Mercury never strays more than about 25 degrees from a Capricorn Sun.
Am I a Capricorn if I was born on December 21?
It depends on the year and the hour. Across 1900 to 2100 in New York time, the whole of December 21 was Sagittarius in 63 years and Capricorn in 16 years. In the other 122 years, the Sun changed sign during the day, so only the birth time decides.
When does the Sun enter Capricorn in 2026?
On December 21, 2026, at 3:50 pm New York time, which is 8:50 pm in London. In Los Angeles, it is 12:50 pm on the same day.
See your own Sun and Mercury
This page gives you the odds. Only your chart shows whether your Mercury sits in the glare, and in which house. Astrovision builds it from your birth date, hour and place. You get a written guide and a podcast made for your chart alone.