Astropy

---
name: astropy
description: Core Python library for astronomy and astrophysics workflows that need Astropy APIs, including units/quantities, coordinates, FITS I/O, tables, time systems, WCS, and cosmology. Use when implementing or debugging astronomical data analysis code with Astropy.
license: BSD-3-Clause license
compatibility: Requires Python 3.11+ with astropy installed (uv for package installation). Some features (object name resolution, site lookups, remote FITS reads, IERS updates) need network access.
metadata: {"version": "1.2", "skill-author": "K-Dense Inc."}
---

# Astropy

## Overview

Astropy is the core Python package for astronomy, providing essential functionality for astronomical research and data analysis. Use astropy for coordinate transformations, unit and quantity calculations, FITS file operations, cosmological calculations, precise time handling, tabular data manipulation, and astronomical image processing.

## When to Use This Skill

Use astropy when tasks involve:
- Converting between celestial coordinate systems (ICRS, Galactic, FK5, AltAz, etc.)
- Working with physical units and quantities (converting Jy to mJy, parsecs to km, etc.)
- Reading, writing, or manipulating FITS files (images or tables)
- Cosmological calculations (luminosity distance, lookback time, Hubble parameter)
- Precise time handling with different time scales (UTC, TAI, TT, TDB) and formats (JD, MJD, ISO)
- Table operations (reading catalogs, cross-matching, filtering, joining)
- WCS transformations between pixel and world coordinates
- Astronomical constants and calculations… load the full skill through Skill Me