README.md•3.88 kB
# mcp-stargazing
Calculate the altitude, rise, and set times of celestial objects (Sun, Moon, planets, stars, and deep-space objects) for any location on Earth, with optional light pollution analysis.
## Features
- **Altitude/Azimuth Calculation**: Get elevation and compass direction for any celestial object.
- **Rise/Set Times**: Determine when objects appear/disappear above the horizon.
- **Light Pollution Analysis**: Load and analyze light pollution maps (GeoTIFF format).
- **Supports**:
- Solar system objects (Sun, Moon, planets)
- Stars (e.g., "sirius")
- Deep-space objects (e.g., "andromeda", "orion_nebula")
- **Time Zone Aware**: Works with local or UTC times.
## Installation
```bash
pip install astropy pytz numpy astroquery rasterio geopy
```
## Usage
### Calculate Altitude/Azimuth
```python src/main.py
from src.celestial import celestial_pos
from astropy.coordinates import EarthLocation
import pytz
from datetime import datetime
# Observer location (New York)
location = EarthLocation(lat=40.7128, lon=-74.0060)
# Time (local timezone-aware)
local_time = pytz.timezone("America/New_York").localize(datetime(2023, 10, 1, 12, 0))
altitude, azimuth = celestial_pos("sun", location, local_time)
print(f"Sun Position: Altitude={altitude:.1f}°, Azimuth={azimuth:.1f}°")
```
### Calculate Rise/Set Times
```python src/main.py
from src.celestial import celestial_rise_set
rise, set_ = celestial_rise_set("andromeda", location, local_time.date())
print(f"Andromeda: Rise={rise.iso}, Set={set_.iso}")
```
### Load Light Pollution Map
```python src/light_pollution.py
from src.light_pollution import load_map
# Load a GeoTIFF light pollution map
vriis_data, bounds, crs, transform = load_map("path/to/map.tif")
print(f"Map Bounds: {bounds}")
```
## API Reference
### `celestial_pos(celestial_object, observer_location, time)` (`src/celestial.py`)
- **Inputs**:
- `celestial_object`: Name (e.g., `"sun"`, `"andromeda"`).
- `observer_location`: `EarthLocation` object.
- `time`: `datetime` (timezone-aware) or Astropy `Time`.
- **Returns**: `(altitude_degrees, azimuth_degrees)`.
### `celestial_rise_set(celestial_object, observer_location, date, horizon=0.0)` (`src/celestial.py`)
- **Inputs**:
- `date`: Timezone-aware `datetime`.
- `horizon`: Horizon elevation (default: 0°).
- **Returns**: `(rise_time, set_time)` as UTC `Time` objects.
### `load_map(map_path)` (`src/light_pollution.py`)
- **Inputs**:
- `map_path`: Path to GeoTIFF file.
- **Returns**: Tuple `(vriis_data, bounds, crs, transform)` for light pollution analysis.
## Testing
Run tests with:
```bash
pytest tests/
```
### Key Test Cases (`tests/test_celestial.py`)
```python tests/test_celestial.py
def test_calculate_altitude_deepspace():
"""Test deep-space object resolution."""
altitude, _ = celestial_pos("andromeda", NYC, Time.now())
assert -90 <= altitude <= 90
def test_calculate_rise_set_sun():
"""Validate Sun rise/set times."""
rise, set_ = celestial_rise_set("sun", NYC, datetime(2023, 10, 1))
assert rise < set_
```
## Project Structure
```
.
├── src/
│ ├── celestial.py # Core celestial calculations
│ ├── light_pollution.py # Light pollution map utilities
│ ├── utils.py # Time/location helpers
│ └── main.py # CLI entry point
├── tests/
│ ├── test_celestial.py
│ └── test_utils.py
└── README.md
```
## Future Work
- Add support for comets/asteroids.
- Optimize SIMBAD queries for offline use.
- Integrate light pollution data into visibility predictions.
### Key Updates:
1. **Light Pollution**: Added `light_pollution.py` to features and API reference.
2. **Dependencies**: Added `rasterio` and `geopy` to installation instructions.
3. **Project Structure**: Clarified file roles and test coverage.
```