Skills astropy
🔭

astropy

Safe ⚙️ External commands📁 Filesystem access⚡ Contains scripts🌐 Network access

Analyze Astronomical Data with Astropy Python Library

Also available from: davila7

Working with astronomical data requires handling complex coordinate systems, file formats, and calculations. This skill provides guidance for using Astropy to process celestial coordinates, FITS files, and cosmological computations.

Supports: Claude Codex Code(CC)
📊 71 Adequate
1

Download the skill ZIP

2

Upload in Claude

Go to Settings → Capabilities → Skills → Upload skill

3

Toggle on and start using

Test it

Using "astropy". How do I convert a coordinate from ICRS to Galactic?

Expected outcome:

  • Create a SkyCoord object with your RA and Dec values in ICRS frame
  • Access the .galactic attribute to transform to Galactic coordinates
  • The result contains .l (longitude) and .b (latitude) in degrees

Using "astropy". What is the luminosity distance at redshift 1.5?

Expected outcome:

  • Using Planck18 cosmology, the luminosity distance at z=1.5 is approximately 11.1 Gpc
  • The angular diameter distance is about 1.78 Gpc
  • The lookback time is roughly 9.4 billion years

Security Audit

Safe
v4 • 1/17/2026

This skill is a documentation reference for the Astropy Python library. All 406 static findings are false positives. The 'backtick execution' detections are triggered by Python code blocks in markdown. The 'C2 keywords' are astronomy terms like 'distance' and 'separation'. The 'Windows SAM' flags are references to SAMP (Simple Application Messaging Protocol), an astronomy interoperability standard.

9
Files scanned
4,827
Lines analyzed
4
findings
4
Total audits

Risk Factors

⚙️ External commands (356)
references/coordinates.md:3 references/coordinates.md:7 references/coordinates.md:9-24 references/coordinates.md:24-30 references/coordinates.md:30-42 references/coordinates.md:42-46 references/coordinates.md:46-55 references/coordinates.md:55-59 references/coordinates.md:59-66 references/coordinates.md:66-72 references/coordinates.md:72-83 references/coordinates.md:83-112 references/coordinates.md:112-130 references/coordinates.md:130-136 references/coordinates.md:136-152 references/coordinates.md:152-158 references/coordinates.md:158-168 references/coordinates.md:168-174 references/coordinates.md:174-185 references/coordinates.md:185-191 references/coordinates.md:191-196 references/coordinates.md:196-202 references/coordinates.md:202-215 references/coordinates.md:215-221 references/coordinates.md:221-236 references/coordinates.md:236-242 references/coordinates.md:242-255 references/coordinates.md:255-264 references/coordinates.md:264-273 references/cosmology.md:3 references/cosmology.md:9-24 references/cosmology.md:24-32 references/cosmology.md:32-41 references/cosmology.md:41-47 references/cosmology.md:47-55 references/cosmology.md:55-61 references/cosmology.md:61-70 references/cosmology.md:70-78 references/cosmology.md:78-80 references/cosmology.md:80-86 references/cosmology.md:86-91 references/cosmology.md:91-97 references/cosmology.md:97-103 references/cosmology.md:103-109 references/cosmology.md:109-111 references/cosmology.md:111-115 references/cosmology.md:115-118 references/cosmology.md:118-126 references/cosmology.md:126-129 references/cosmology.md:129-135 references/cosmology.md:135-138 references/cosmology.md:138-146 references/cosmology.md:146-150 references/cosmology.md:150-156 references/cosmology.md:156-159 references/cosmology.md:159-165 references/cosmology.md:165-168 references/cosmology.md:168-174 references/cosmology.md:174-180 references/cosmology.md:180-184 references/cosmology.md:184-187 references/cosmology.md:187-193 references/cosmology.md:193-204 references/cosmology.md:204-210 references/cosmology.md:210-217 references/cosmology.md:217-223 references/cosmology.md:223-234 references/cosmology.md:234-242 references/cosmology.md:242-248 references/cosmology.md:248-254 references/cosmology.md:254-260 references/cosmology.md:260-264 references/cosmology.md:264-271 references/cosmology.md:271-275 references/cosmology.md:275-280 references/cosmology.md:280-284 references/cosmology.md:284-289 references/cosmology.md:289-293 references/cosmology.md:293-300 references/fits.md:3 references/fits.md:9-22 references/fits.md:22-26 references/fits.md:26-30 references/fits.md:30-36 references/fits.md:36-39 references/fits.md:39-45 references/fits.md:45-50 references/fits.md:50-55 references/fits.md:55-56 references/fits.md:56-58 references/fits.md:58-65 references/fits.md:65-69 references/fits.md:69-79 references/fits.md:79-85 references/fits.md:85-98 references/fits.md:98-102 references/fits.md:102-118 references/fits.md:118-124 references/fits.md:124-132 references/fits.md:132-138 references/fits.md:138-150 references/fits.md:150-156 references/fits.md:156-171 references/fits.md:171-177 references/fits.md:177-180 references/fits.md:180-186 references/fits.md:186-202 references/fits.md:202-206 references/fits.md:206-223 references/fits.md:223-229 references/fits.md:229-247 references/fits.md:247-251 references/fits.md:251-265 references/fits.md:265-270 references/fits.md:270-271 references/fits.md:271-272 references/fits.md:272-273 references/fits.md:273-274 references/fits.md:274-275 references/fits.md:275-276 references/fits.md:276-277 references/fits.md:277-283 references/fits.md:283-292 references/fits.md:292-296 references/fits.md:296-303 references/fits.md:303-309 references/fits.md:309-333 references/fits.md:333-337 references/fits.md:337-344 references/fits.md:344-350 references/fits.md:350-358 references/fits.md:358-362 references/fits.md:362-366 references/fits.md:366-376 references/fits.md:376-384 references/fits.md:384-388 references/fits.md:388-396 references/tables.md:3 references/tables.md:9-25 references/tables.md:25-29 references/tables.md:29-37 references/tables.md:37-41 references/tables.md:41-50 references/tables.md:50-54 references/tables.md:54-59 references/tables.md:59-65 references/tables.md:65-80 references/tables.md:80-84 references/tables.md:84-90 references/tables.md:90-94 references/tables.md:94-102 references/tables.md:102-108 references/tables.md:108-122 references/tables.md:122-126 references/tables.md:126-138 references/tables.md:138-142 references/tables.md:142-147 references/tables.md:147-151 references/tables.md:151-160 references/tables.md:160-164 references/tables.md:164-174 references/tables.md:174-180 references/tables.md:180-193 references/tables.md:193-197 references/tables.md:197-207 references/tables.md:207-217 references/tables.md:217-229 references/tables.md:229-233 references/tables.md:233-244 references/tables.md:244-248 references/tables.md:248-260 references/tables.md:260-266 references/tables.md:266-273 references/tables.md:273-277 references/tables.md:277-284 references/tables.md:284-288 references/tables.md:288-299 references/tables.md:299-303 references/tables.md:303-314 references/tables.md:314-318 references/tables.md:318-324 references/tables.md:324-330 references/tables.md:330-344 references/tables.md:344-348 references/tables.md:348-361 references/tables.md:361-367 references/tables.md:367-376 references/tables.md:376-380 references/tables.md:380-390 references/tables.md:390-396 references/tables.md:396-405 references/tables.md:405-409 references/tables.md:409-415 references/tables.md:415-419 references/tables.md:419-425 references/tables.md:425-429 references/tables.md:429-443 references/tables.md:443-447 references/tables.md:447-456 references/tables.md:456-462 references/tables.md:462-477 references/tables.md:477-481 references/tables.md:481-489 references/time.md:3 references/time.md:9-28 references/time.md:28-32 references/time.md:32-40 references/time.md:40-46 references/time.md:46-79 references/time.md:79-85 references/time.md:85-106 references/time.md:106-110 references/time.md:110-122 references/time.md:122-128 references/time.md:128-142 references/time.md:142-146 references/time.md:146-152 references/time.md:152-158 references/time.md:158-171 references/time.md:171-175 references/time.md:175-188 references/time.md:188-192 references/time.md:192-200 references/time.md:200-206 references/time.md:206-220 references/time.md:220-224 references/time.md:224-241 references/time.md:241-245 references/time.md:245-248 references/time.md:248-254 references/time.md:254-269 references/time.md:269-277 references/time.md:277-284 references/time.md:284-288 references/time.md:288-295 references/time.md:295-301 references/time.md:301-312 references/time.md:312-318 references/time.md:318-330 references/time.md:330-334 references/time.md:334-343 references/time.md:343-347 references/time.md:347-359 references/time.md:359-363 references/time.md:363-372 references/time.md:372-376 references/time.md:376-397 references/units.md:3 references/units.md:9-20 references/units.md:20-22 references/units.md:22 references/units.md:22-23 references/units.md:23-26 references/units.md:26-30 references/units.md:30-32 references/units.md:32-38 references/units.md:38-44 references/units.md:44-55 references/units.md:55-61 references/units.md:61-68 references/units.md:68-74 references/units.md:74-89 references/units.md:89-95 references/units.md:95-104 references/units.md:104-109 references/units.md:109-112 references/units.md:112-115 references/units.md:115-118 references/units.md:118-121 references/units.md:121-124 references/units.md:124-127 references/units.md:127-130 references/units.md:130-136 references/units.md:136-146 references/units.md:146-152 references/units.md:152-157 references/units.md:157-161 references/units.md:161-167 references/units.md:167-173 references/units.md:173-178 references/wcs_and_other_modules.md:9-16 references/wcs_and_other_modules.md:16-20 references/wcs_and_other_modules.md:20-30 references/wcs_and_other_modules.md:30-34 references/wcs_and_other_modules.md:34-45 references/wcs_and_other_modules.md:45-49 references/wcs_and_other_modules.md:49-61 references/wcs_and_other_modules.md:61-65 references/wcs_and_other_modules.md:65-75 references/wcs_and_other_modules.md:75-79 references/wcs_and_other_modules.md:79-83 references/wcs_and_other_modules.md:83-91 references/wcs_and_other_modules.md:91-115 references/wcs_and_other_modules.md:115-119 references/wcs_and_other_modules.md:119-130 references/wcs_and_other_modules.md:130-138 references/wcs_and_other_modules.md:138-156 references/wcs_and_other_modules.md:156-160 references/wcs_and_other_modules.md:160-175 references/wcs_and_other_modules.md:175-179 references/wcs_and_other_modules.md:179-187 references/wcs_and_other_modules.md:187-195 references/wcs_and_other_modules.md:195-210 references/wcs_and_other_modules.md:210-214 references/wcs_and_other_modules.md:214-227 references/wcs_and_other_modules.md:227-231 references/wcs_and_other_modules.md:231-239 references/wcs_and_other_modules.md:239-245 references/wcs_and_other_modules.md:245-271 references/wcs_and_other_modules.md:271-275 references/wcs_and_other_modules.md:275-286 references/wcs_and_other_modules.md:286-292 references/wcs_and_other_modules.md:292-304 references/wcs_and_other_modules.md:304-310 references/wcs_and_other_modules.md:310-324 references/wcs_and_other_modules.md:324-330 references/wcs_and_other_modules.md:330-336 references/wcs_and_other_modules.md:336-340 references/wcs_and_other_modules.md:340-347 references/wcs_and_other_modules.md:347-353 references/wcs_and_other_modules.md:353-373 SKILL.md:29-58 SKILL.md:58-62 SKILL.md:62-68 SKILL.md:68-73 SKILL.md:73-75 SKILL.md:75-80 SKILL.md:80-88 SKILL.md:88-90 SKILL.md:90-103 SKILL.md:103-105 SKILL.md:105-119 SKILL.md:119-121 SKILL.md:121-135 SKILL.md:135-137 SKILL.md:137-150 SKILL.md:150-152 SKILL.md:152-163 SKILL.md:163-167 SKILL.md:167-189 SKILL.md:189-195 SKILL.md:195-201 SKILL.md:201-221 SKILL.md:221-225 SKILL.md:225-246 SKILL.md:246-250 SKILL.md:250-270 SKILL.md:270-274 SKILL.md:274-298 SKILL.md:298-322 SKILL.md:322-323 SKILL.md:323-324 SKILL.md:324-325 SKILL.md:325-326 SKILL.md:326-327 SKILL.md:327-328
📁 Filesystem access (4)
references/fits.md:37 references/fits.md:390 references/tables.md:407 references/tables.md:411
⚡ Contains scripts (1)
references/wcs_and_other_modules.md:215-216
🌐 Network access (5)
references/wcs_and_other_modules.md:334 skill-report.json:6 SKILL.md:315 SKILL.md:316 SKILL.md:317
Audited by: claude View Audit History →

Quality Score

45
Architecture
100
Maintainability
87
Content
19
Community
100
Security
91
Spec Compliance

What You Can Build

Convert Celestial Coordinates

Transform coordinates between different reference frames for observation planning or catalog cross-matching.

Process FITS Astronomy Files

Read and analyze FITS format telescope images and catalogs for research or data pipeline development.

Calculate Cosmological Distances

Compute luminosity distances, lookback times, and Hubble parameters for distant galaxy analysis.

Try These Prompts

Basic Coordinate Conversion 
How do I convert ICRS coordinates (RA=10.5 deg, Dec=41.2 deg) to Galactic coordinates using astropy?
Read FITS File 
Show me how to open a FITS file, read the image data from the first extension, and access header keywords like EXPTIME.
Cosmology Calculation 
Calculate the luminosity distance and lookback time to a galaxy at redshift z=2.5 using the Planck18 cosmology.
Catalog Cross-Matching 
I have two astronomical catalogs with RA/Dec columns. How do I cross-match them within 1 arcsecond using astropy coordinates?

Best Practices

  • Always attach units to quantities using astropy.units to prevent dimensional errors
  • Use context managers when opening FITS files to ensure proper resource cleanup
  • Process coordinate arrays rather than looping for better performance

Avoid

  • Do not hardcode unit conversions manually when astropy can handle them automatically
  • Avoid looping over individual coordinates when array operations are available
  • Do not assume coordinate frames match without explicit verification

Frequently Asked Questions

What is astropy used for?
Astropy is a Python library for astronomy providing tools for coordinates, units, FITS files, cosmology, time handling, and data tables.
How do I install astropy?
Install with pip: 'pip install astropy' or with all optional dependencies: 'pip install astropy[all]'.
What coordinate systems does astropy support?
Astropy supports ICRS, FK5, FK4, Galactic, AltAz, Ecliptic, Galactocentric, and many other astronomical reference frames.
Can astropy read FITS files?
Yes, astropy.io.fits module provides full support for reading, writing, and manipulating FITS files including headers and data.
What cosmological models are available?
Built-in models include Planck18, Planck15, WMAP9, WMAP7, and WMAP5. You can also create custom cosmological models.
How do I handle time in astropy?
Use astropy.time.Time for precise time handling with support for UTC, TAI, TT, TDB scales and formats like JD, MJD, ISO.

Developer Details

Author

K-Dense-AI

License

BSD-3-Clause license

Repository

https://github.com/K-Dense-AI/claude-scientific-skills/tree/main/scientific-skills/astropy

Ref

main

File structure

📁 references/

📄 coordinates.md

📄 cosmology.md

📄 fits.md

📄 tables.md

📄 time.md

📄 units.md

📄 wcs_and_other_modules.md

📄 SKILL.md