Panchanga Calculator

A TypeScript/React application that calculates Hindu astrological elements (Panchanga) for any given date based on Kathmandu, Nepal's coordinates.

Features

• Calculates daily Panchanga elements:
  • Tithi (Lunar Day)
  • Nakshatra (Lunar Mansion)
  • Yoga (Sun-Moon Angular Relationship)
  • Karana (Half Lunar Day)
  • Rashi (Moon Sign)
• Provides Solar calendar information:
  • Solar Month (based on sidereal sun position)
  • Solar Day (progress in current solar month)
  • Days in Month (variable 29-32 days)
• Shows timings for:
  • Sunrise and Sunset
  • Tithi Start and End times
• Includes detailed debug information for astronomical calculations
• Responsive design with Tailwind CSS
• Built with TypeScript for type safety

Prerequisites

• Node.js (v16 or higher)
• npm (v7 or higher) or yarn (v1.22 or higher)
• Git (for cloning the repository)

Installation

1. Clone the repository:

git clone https://github.com/khumnath/panchanga-calculator.git
cd panchanga-calculator

2. Install dependencies:

npm install
# or
yarn install

3. Start the development server:

npm run dev
# or
yarn dev

4. Open your browser and navigate to http://localhost:5173

Build

To create a production build:

npm run build
# or
yarn build

The build output will be in the docs directory.

Technical Details

• Frontend: React 18 with TypeScript
• Styling: Tailwind CSS for modern, utility-first styling
• Build Tool: Vite for fast development and optimized builds
• Location: Fixed to Kathmandu, Nepal (27.7172°N, 85.324°E)
• Time Zone: Nepal Time (UTC+5:45)
• Package Manager: npm or yarn

Astronomical Calculations

The calculator implements several astronomical algorithms:

• Lahiri Ayanamsa for sidereal calculations
• Solar and Lunar position calculations
• Sunrise/Sunset computations for given latitude/longitude
• Tithi (lunar phase) boundary detection with iterative refinement
• Solar month boundaries based on sidereal solar longitudes

Limitations

• Calculations are optimized for Kathmandu, Nepal
• Results may vary from traditional almanacs due to:
  • Simplified astronomical formulae
  • Different ayanamsa (precession) models
  • Rounding of times and angles
• Date range: 1900-2100 CE for best accuracy
• Solar day calculations may occasionally differ from traditional calendars
• Tithi boundary times are approximate within ±2 minutes
• All calculations are geometric (no atmospheric refraction)

Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

Please ensure your code follows the existing code style and appropriate comments.

License

This project is licensed under the GNU General Public License v3.0 or later - see the LICENSE file for details.

Copyright (C) 2025 Khumnath Cg nath.khum@gmail.com

Acknowledgments

• Based on traditional Hindu astronomical calculations
• Modern astronomical algorithms adapted for web usage
• Inspired by traditional Panchanga almanacs
• UI design inspired by modern web applications