Solarius

Solarius is a Python library for calculating your precise solar return — the exact moment the Sun returns to the same ecliptic longitude it occupied at your birth — according to the Gregorian calendar. This real birthday and can differ from your civil birthday in a given future year due to leap years, etc.

To give you accurate results anywhere in the world, Solarius uses:

• skyfield to compute precise positions of celestial bodies.
• geopy to map the names of cities and countries to coordinates.
• timezonefinder for mapping geographical coordinates to timezones.
• pytz to convert between UTC and local times using regional daylight-saving rules.

📦 Installation

pip install solarius

Built for Python 3.12 or above.

🚀 Quick Start

from solarius.model import SolarReturnCalculator

calculator = SolarReturnCalculator(ephemeris_file="de421.bsp")

# Predict without printing
date_str, time_str, tz_name = calculator.predict(
    official_birthday="18-01-1996",
    official_birth_time="02:30",
    birth_country="France",
    birth_city="Paris",
    current_country="France",
    current_city="Paris",
    target_year="2026"
)
print(date_str, time_str, tz_name)

# Or use the convenience printer
calculator.print_real_birthday(
    official_birthday="18-01-1996",
    official_birth_time="02:30",
    birth_country="France",
    birth_city="Paris",
    current_country="France",
    current_city="Paris",
    target_year="2026"
)

📚 API Reference

See here