Secondary Progressions

Calculate secondary progressions (also called "a day for a year" progressions). Each day after birth corresponds to one year of life, creating a progressed chart that slowly evolves over time.

Required Module

Requires the progression:calc module.

Calculate Progressions

curl -X POST "https://api.astroapi.cloud/api/calc/progressions" \
  -H "X-Api-Key: your-api-key" \
  -H "Content-Type: application/json" \
  -d '{
    "birthDateTime": "1990-06-15T14:30",
    "birthLocation": {
      "longitude": -0.1278,
      "latitude": 51.5074,
      "timezone": "Europe/London"
    },
    "targetDate": "2024-06-15T12:00",
    "houseSystem": "placidus",
    "language": "en",
    "includeText": true,
    "includeReadableEntities": true
  }'

Parameters

Parameter	Type	Required	Description
birthDateTime	string	Yes	Birth date and time in YYYY-MM-DDTHH:mm format
birthLocation	object	Yes	Birth location (longitude, latitude, timezone)
targetDate	string	Yes	Target date to progress the chart to, in YYYY-MM-DDTHH:mm format
houseSystem	string	No	House system (default: "placidus")
language	string	No	Language code for text content (default: "en")
includeText	boolean	No	Include interpretation text (default: false)
includeReadableEntities	boolean	No	Include human-readable entity titles (default: false)
points	array	No	Celestial points to include in the calculation
orbs	object	No	Custom orb values per aspect type

Location Object

{
    "longitude": -0.1278,
    "latitude": 51.5074,
    "timezone": "Europe/London"
}

Response

{
    "data": {
        "progressedDate": "2024-06-15T12:00",
        "natalDate": "1990-06-15T14:30",
        "targetDate": "2024-06-15T12:00",
        "aspects": [
            {
                "point1": "sun",
                "point2": "moon",
                "aspect": "sextile",
                "orb": 1.2,
                "applying": true
            }
        ],
        "aspectsToNatal": [
            {
                "point1": "moon",
                "point2": "sun",
                "aspect": "conjunction",
                "orb": 0.4,
                "applying": false,
                "text": "Progressed Moon conjunct natal Sun marks a significant personal turning point..."
            }
        ],
        "points": {
            "sun": {
                "longitude": 108.3,
                "latitude": 0.0,
                "sign": "cancer",
                "house": 10,
                "retrograde": false
            },
            "moon": {
                "longitude": 108.7,
                "latitude": -1.5,
                "sign": "cancer",
                "house": 10,
                "retrograde": false
            },
            "mercury": {
                "longitude": 95.1,
                "latitude": 0.8,
                "sign": "cancer",
                "house": 9,
                "retrograde": true
            }
        },
        "natalPoints": {
            "sun": {
                "longitude": 84.5,
                "latitude": 0.0,
                "sign": "gemini",
                "house": 10,
                "retrograde": false
            }
        },
        "houses": {
            "1": { "cusp": 180.5, "sign": "libra" },
            "10": { "cusp": 84.5, "sign": "gemini" }
        },
        "charts": {
            "biWheel": {
                "title": "Progressed / Natal Bi-wheel",
                "url": "https://api.astroapi.cloud/api/chart/..."
            },
            "progressed": {
                "title": "Progressed Chart",
                "url": "https://api.astroapi.cloud/api/chart/..."
            },
            "natal": {
                "title": "Natal Chart",
                "url": "https://api.astroapi.cloud/api/chart/..."
            }
        }
    }
}

Response Fields

Field	Type	Description
progressedDate	string	The date the chart was progressed to
natalDate	string	The original birth date and time
targetDate	string	The target date provided in the request
aspects	array	Aspects between progressed planets (within the progressed chart)
aspectsToNatal	array	Aspects from progressed planets to natal planets
points	object	Progressed planetary positions
natalPoints	object	Natal planetary positions for reference
houses	object	Progressed house cusps
charts.biWheel	object	Bi-wheel showing progressed chart overlaid on natal chart
charts.progressed	object	Standalone progressed chart image URL
charts.natal	object	Natal chart image URL

Understanding Secondary Progressions

Secondary progressions use the symbolic formula of one day = one year. To find the progressed chart for age 34 (34 years after birth), the ephemeris positions for 34 days after the birth date are used.

Progressed Moon

The progressed Moon moves the fastest of all progressed points, changing sign roughly every 2.5 years. It is the most commonly tracked progressed point and provides insight into current emotional themes.

Progressed Sun

The progressed Sun moves approximately one degree per year. A progressed Sun sign change is a significant life event that occurs roughly every 30 years.

Progressed-to-Natal Aspects

The aspectsToNatal array shows aspects from the progressed chart to the natal chart. These are the primary indicators used in progression forecasting:

{
    "point1": "moon",
    "point2": "sun",
    "aspect": "conjunction",
    "orb": 0.4,
    "applying": false,
    "text": "Progressed Moon conjunct natal Sun marks a significant personal turning point..."
}

Aspects with small orbs (under 1 degree) are typically the most significant. Applying aspects (moving toward exactness) show upcoming themes, while separating aspects show energies that are passing.