# Astropy **URL:** https://community.openastronomy.org/c/astropy/8.md [Latest](https://community.openastronomy.org/latest.md) · [Categories](https://community.openastronomy.org/categories.md) · [Tags](https://community.openastronomy.org/tags.md) --- ## [About the Astropy category](https://community.openastronomy.org/t/about-the-astropy-category/16)
**Author:** [@Cadair](https://community.openastronomy.org/u/Cadair)\ **Replies:** 0
Talk about Astropy, its affiliated packages, or any posts about doing astronomy/astrophysics with Python. When participating in the discussions in this category please read and respect the Astropy Code of Conduct as wel… --- ## [Issue with astroquery? basic examples don't seem to work](https://community.openastronomy.org/t/issue-with-astroquery-basic-examples-dont-seem-to-work/1449)
**Author:** [@jyoung](https://community.openastronomy.org/u/jyoung)\ **Replies:** 0\ **Last updated:** [August 28, 2026, 5:02pm UTC](https://community.openastronomy.org/t/issue-with-astroquery-basic-examples-dont-seem-to-work/1449 "2026-08-28T17:02:22Z")
Hi, I’m trying to use astroquery to search for archival data. I’ve used MAST frequently, but I’m new to astroquery. I’m finding that some of the examples from the astroquery docs don’t run as expected. For example, when… --- ## [Astropy Voting Member Election - August 2026](https://community.openastronomy.org/t/astropy-voting-member-election-august-2026/1439)
**Author:** [@ceb8](https://community.openastronomy.org/u/ceb8)\ **Replies:** 0\ **Last updated:** [July 14, 2026, 6:56pm UTC](https://community.openastronomy.org/t/astropy-voting-member-election-august-2026/1439 "2026-07-14T18:56:25Z")
The next Astropy Voting Member election will be on August 11-24. We are accepting nominations for new voting members until the end of Tuesday 28 July (anywhere on Earth). To nominate someone (or yourself) to be a voting… --- ## [Barycentric z coordinates solar system wrong?](https://community.openastronomy.org/t/barycentric-z-coordinates-solar-system-wrong/1435)
**Author:** [@CosmoDM](https://community.openastronomy.org/u/CosmoDM)\ **Replies:** 1\ **Last updated:** [July 2, 2026, 8:43am UTC](https://community.openastronomy.org/t/barycentric-z-coordinates-solar-system-wrong/1435 "2026-07-02T08:43:03Z")
When getting barycentric coordinates for solar system planets, the positions and velocities seem to be scaled up along the z direction (or the units are wrong). For example, getting the coordinates of Uranus at the curre… --- ## [Using GCRS coordinates with WCS objects](https://community.openastronomy.org/t/using-gcrs-coordinates-with-wcs-objects/1407)
**Author:** [@svank](https://community.openastronomy.org/u/svank)\ **Replies:** 0\ **Last updated:** [April 28, 2026, 11:00pm UTC](https://community.openastronomy.org/t/using-gcrs-coordinates-with-wcs-objects/1407 "2026-04-28T23:00:04Z")
I’m looking for guidance on the best way to have GCRS coordinates interact with WCS objects, and whether I’m handling coordinate frames correctly. For the PUNCH mission (a set of four wide-field imager satellites observi… --- ## [Help needed: astrophysics tutorial ideas for teens](https://community.openastronomy.org/t/help-needed-astrophysics-tutorial-ideas-for-teens/1404)
**Author:** [@ludovicg](https://community.openastronomy.org/u/ludovicg)\ **Replies:** 0\ **Last updated:** [April 1, 2026, 3:53pm UTC](https://community.openastronomy.org/t/help-needed-astrophysics-tutorial-ideas-for-teens/1404 "2026-04-01T15:53:18Z")
Hi everyone, My 12-year-old son wants to be an astrophysicist. I’m encouraging him by introducing him to (or exploring with him) concepts and news in this field. As part of my job, I work with econometrics and do quite… --- ## [Introduction as a GSoC Contributor (2026)](https://community.openastronomy.org/t/introduction-as-a-gsoc-contributor-2026/1403)
**Author:** [@adwait-ops](https://community.openastronomy.org/u/adwait-ops)\ **Replies:** 0\ **Last updated:** [March 31, 2026, 1:43pm UTC](https://community.openastronomy.org/t/introduction-as-a-gsoc-contributor-2026/1403 "2026-03-31T13:43:05Z")
I am Adwait Amlekar, a Mechanical Engineering undergraduate student with a strong interest in computational science, and complex problem solving. My experience so far has been shaped by working with programming language… --- ## [Testing low-level layer to harden astropy's core stability (GSOC 2026)](https://community.openastronomy.org/t/testing-low-level-layer-to-harden-astropys-core-stability-gsoc-2026/1378)
**Author:** [@Abu-bakkar-siddique](https://community.openastronomy.org/u/Abu-bakkar-siddique)\ **Replies:** 3\ **Last updated:** [March 15, 2026, 11:40am UTC](https://community.openastronomy.org/t/testing-low-level-layer-to-harden-astropys-core-stability-gsoc-2026/1378 "2026-03-15T11:40:53Z")
Hi all, I need some clarification on the scope and scale of the proposed project hardening astropy’s core stability about testing low-level layer extensions. Does building a more fundamental test suite for this low-le… --- ## [Starting up with astropy](https://community.openastronomy.org/t/starting-up-with-astropy/1363)
**Author:** [@tarun](https://community.openastronomy.org/u/tarun)\ **Replies:** 0\ **Last updated:** [March 4, 2026, 4:35pm UTC](https://community.openastronomy.org/t/starting-up-with-astropy/1363 "2026-03-04T16:35:27Z")
Hi everyone, I’m Tarun, a first-year CSE student interested in contributing to Astropy for GSoC. I know Python and basic C/C++. I’m currently exploring the Astropy documentation and would love guidance on beginner issu… --- ## [Speeding up Atropy calculations](https://community.openastronomy.org/t/speeding-up-atropy-calculations/1353)
**Author:** [@sean.murphy](https://community.openastronomy.org/u/sean.murphy)\ **Replies:** 0\ **Last updated:** [February 19, 2026, 3:33pm UTC](https://community.openastronomy.org/t/speeding-up-atropy-calculations/1353 "2026-02-19T15:33:04Z")
I’m attempting to use astropy to calculate the solar & lunar illumination over a sequence of regularly spaced intervals. My code seems to work, but it seems pretty slow - I’m calculating both values every 15 minutes over… --- ## [Preserving compression quantization on rewrite](https://community.openastronomy.org/t/preserving-compression-quantization-on-rewrite/1334)
**Author:** [@jbosch](https://community.openastronomy.org/u/jbosch)\ **Replies:** 9\ **Last updated:** [February 19, 2026, 2:47pm UTC](https://community.openastronomy.org/t/preserving-compression-quantization-on-rewrite/1334 "2026-02-19T14:47:10Z")
I’d like to use Astropy to read one FITS file with some tile-compressed image HDU and write a new one that preserves the original tile-compressed image without quantizing again (but does modify the header, add some other… --- ## [Elided columns and number formats in TimeSeries](https://community.openastronomy.org/t/elided-columns-and-number-formats-in-timeseries/1161)
**Author:** [@liamh](https://community.openastronomy.org/u/liamh)\ **Replies:** 4\ **Last updated:** [January 1, 2026, 11:13pm UTC](https://community.openastronomy.org/t/elided-columns-and-number-formats-in-timeseries/1161 "2026-01-01T23:13:09Z")
By default, TimeSeries display with elided columns “…”, as can be seen in the first example in the documentation. In my case, I have a three-vector, and the middle value is elided. This happens even when I have a wide sc… --- ## [ITRS/GCRF transform validation against Spice & SOFA](https://community.openastronomy.org/t/itrs-gcrf-transform-validation-against-spice-sofa/881)
**Author:** [@bbercovici](https://community.openastronomy.org/u/bbercovici)\ **Replies:** 4\ **Last updated:** [November 28, 2025, 5:28pm UTC](https://community.openastronomy.org/t/itrs-gcrf-transform-validation-against-spice-sofa/881 "2025-11-28T17:28:10Z")
Hello Astropy community. I’m struggling to get a ITRF/GCRF conversion from Astropy, Spice and Sofa that are in agreement with each other. Basically, Spice and Sofa are within 4 arcsecs, using the following implementati… --- ## [Are round-trip conversions between geocentric and geodetic EarthLocation expected to be stable?](https://community.openastronomy.org/t/are-round-trip-conversions-between-geocentric-and-geodetic-earthlocation-expected-to-be-stable/1314)
**Author:** [@bjmc](https://community.openastronomy.org/u/bjmc)\ **Replies:** 1\ **Last updated:** [November 25, 2025, 9:24pm UTC](https://community.openastronomy.org/t/are-round-trip-conversions-between-geocentric-and-geodetic-earthlocation-expected-to-be-stable/1314 "2025-11-25T21:24:49Z")
Hello, I’ve run into an issue with Astropy causing test failures for us. I’m not sure if this is expected behavior / something I’m doing wrong, but when converting between geocentic and geodetic EarthLocation coordinates… --- ## [2025 CoCo Election: Derek Homeier](https://community.openastronomy.org/t/2025-coco-election-derek-homeier/1312)
**Author:** [@dhomeier](https://community.openastronomy.org/u/dhomeier)\ **Replies:** 0\ **Last updated:** [October 18, 2025, 12:11am UTC](https://community.openastronomy.org/t/2025-coco-election-derek-homeier/1312 "2025-10-18T00:11:51Z")
I am very honoured to be nominated as candidate for the Astropy Coordination Committee. I have used Python and its scientific ecosystem for a major part of my research career in theoretical astrophysics as a free – open… --- ## [2025 CoCo Election: Nathaniel Starkman](https://community.openastronomy.org/t/2025-coco-election-nathaniel-starkman/1311)
**Author:** [@nstarman](https://community.openastronomy.org/u/nstarman)\ **Replies:** 0\ **Last updated:** [October 17, 2025, 3:12am UTC](https://community.openastronomy.org/t/2025-coco-election-nathaniel-starkman/1311 "2025-10-17T03:12:27Z")
It is my honor to accept the nomination for the Astropy Coordination Committee (CoCo). My involvement with Astropy began in 2020 as a PhD student, motivated by a desire to contribute back to the software that has under… --- ## [2025 CoCo Election: Eero Vaher](https://community.openastronomy.org/t/2025-coco-election-eero-vaher/1310)
**Author:** [@eerovaher](https://community.openastronomy.org/u/eerovaher)\ **Replies:** 0\ **Last updated:** [October 16, 2025, 10:48pm UTC](https://community.openastronomy.org/t/2025-coco-election-eero-vaher/1310 "2025-10-16T22:48:34Z")
I am announcing my participation in the 2025 Astropy Coordination Committee election. Although I have been a maintainer for astropy.coordinates for a couple of years by now, I am still a relative newcomer to the project… --- ## [2025 CoCo Election: Kyle Westfall](https://community.openastronomy.org/t/2025-coco-election-kyle-westfall/1309)
**Author:** [@KyleWestfall](https://community.openastronomy.org/u/KyleWestfall)\ **Replies:** 0\ **Last updated:** [October 16, 2025, 10:16pm UTC](https://community.openastronomy.org/t/2025-coco-election-kyle-westfall/1309 "2025-10-16T22:16:35Z")
I am honored to have been nominated and pleased to stand in this year’s election for the Astropy Coordination Committee. Since 2016, I have been a staff scientist at the University of California Observatories. I receiv… --- ## [2025 CoCo Election: Timothy Pickering](https://community.openastronomy.org/t/2025-coco-election-timothy-pickering/1308)
**Author:** [@tepickering](https://community.openastronomy.org/u/tepickering)\ **Replies:** 0\ **Last updated:** [October 15, 2025, 7:32pm UTC](https://community.openastronomy.org/t/2025-coco-election-timothy-pickering/1308 "2025-10-15T19:32:28Z")
I am honored to have been nominated to be a member of the Coordination Committee. I have been involved with AstroPy at least peripherally since its inception. Over the past decade I have been more directly involved and a… --- ## [Cycle 5 Funding Round](https://community.openastronomy.org/t/cycle-5-funding-round/1307)
**Author:** [@nstarman](https://community.openastronomy.org/u/nstarman)\ **Replies:** 0\ **Last updated:** [October 15, 2025, 6:44pm UTC](https://community.openastronomy.org/t/cycle-5-funding-round/1307 "2025-10-15T18:44:52Z")
We are happy to announce the opening of the Astropy Cycle 5 Funding Request (proposal) call! The cycle is open starting now but the first key deadline is for initial drafts of FRs by October 31st. The details for the FR … --- ## [Astropy Workshop at AAS 247](https://community.openastronomy.org/t/astropy-workshop-at-aas-247/1302)
**Author:** [@Cadair](https://community.openastronomy.org/u/Cadair)\ **Replies:** 0\ **Last updated:** [October 6, 2025, 12:52pm UTC](https://community.openastronomy.org/t/astropy-workshop-at-aas-247/1302 "2025-10-06T12:52:05Z")
Register yourself or a student for the ‘Python and Astropy for Astronomical Data Analysis’ workshop at AAS on January 4, 2026. #aas247 You’ll get a broad overview of the astropy functionality that powers astronomy, taug… --- ## [Astropy does not respond](https://community.openastronomy.org/t/astropy-does-not-respond/1256)
**Author:** [@SbleitZ](https://community.openastronomy.org/u/SbleitZ)\ **Replies:** 3\ **Last updated:** [September 11, 2025, 2:23pm UTC](https://community.openastronomy.org/t/astropy-does-not-respond/1256 "2025-09-11T14:23:50Z")
""" astropy 7.1.0 astropy-iers-data 0.2025.6.30.0.39.40 astroquery 0.4.10 """ from astroquery.skyview import SkyView print(SkyView.list\_surveys… --- ## [Compute vernal equinox in Astropy](https://community.openastronomy.org/t/compute-vernal-equinox-in-astropy/1250)
**Author:** [@typiconman](https://community.openastronomy.org/u/typiconman)\ **Replies:** 0\ **Last updated:** [June 12, 2025, 7:34am UTC](https://community.openastronomy.org/t/compute-vernal-equinox-in-astropy/1250 "2025-06-12T07:34:53Z")
I need to compute the date and time of the vernal equinox for a given year. I have the following code: from astropy.time import Time from astropy.coordinates import get\_sun, AltAz, EarthLocation import numpy as np impor… --- ## [Removing labels, ticks, formatters in a plot with WCS projection](https://community.openastronomy.org/t/removing-labels-ticks-formatters-in-a-plot-with-wcs-projection/410)
**Author:** [@Vital-Fernandez](https://community.openastronomy.org/u/Vital-Fernandez)\ **Replies:** 4\ **Last updated:** [April 7, 2025, 12:34am UTC](https://community.openastronomy.org/t/removing-labels-ticks-formatters-in-a-plot-with-wcs-projection/410 "2025-04-07T00:34:36Z")
I want to plot a grid of images of a galaxy with matplotlib while only keeping the RA and DEC ticks/labels on the left and lower edge plots to make the figure less cluttered. However, I have noticed that once you use th… --- ## [Cannot import name 'update\_default\_config' from 'astropy.config.configuration'](https://community.openastronomy.org/t/cannot-import-name-update-default-config-from-astropy-config-configuration/1221)
**Author:** [@JeffMangum](https://community.openastronomy.org/u/JeffMangum)\ **Replies:** 0\ **Last updated:** [March 25, 2025, 2:55pm UTC](https://community.openastronomy.org/t/cannot-import-name-update-default-config-from-astropy-config-configuration/1221 "2025-03-25T14:55:55Z")
Hello, Recent upgrade to astropy 6.0.1 (within python 3.9.21) has resulted in the following error when I from reproject import reproject\_interp: ImportError: cannot import name ‘update\_default\_config’ from ‘astropy.con… --- ## [Announcing the first astropy user survey - closes April 1](https://community.openastronomy.org/t/announcing-the-first-astropy-user-survey-closes-april-1/1212)
**Author:** [@jeffjennings](https://community.openastronomy.org/u/jeffjennings)\ **Replies:** 0\ **Last updated:** [February 28, 2025, 3:27pm UTC](https://community.openastronomy.org/t/announcing-the-first-astropy-user-survey-closes-april-1/1212 "2025-02-28T15:27:59Z")
The Astropy Project is running its first user survey! If you’re interested, please take 15 minutes to give your input before April 1 to help us better understand how astropy is being used, how it can be improved, and how… --- ## [The earth is 0.4 AU from the earth?](https://community.openastronomy.org/t/the-earth-is-0-4-au-from-the-earth/1203)
**Author:** [@yoachim](https://community.openastronomy.org/u/yoachim)\ **Replies:** 3\ **Last updated:** [February 14, 2025, 5:03pm UTC](https://community.openastronomy.org/t/the-earth-is-0-4-au-from-the-earth/1203 "2025-02-14T17:03:57Z")
Trying to get apparent positions of things in the solar system, it seems like odd things happen when the object gets too close to the earth. Here’s the relevant cells from my notebook that shows if I get the position of … --- ## [Question about SkyCoord. radial\_velocity\_correction](https://community.openastronomy.org/t/question-about-skycoord-radial-velocity-correction/1199)
**Author:** [@caseylam](https://community.openastronomy.org/u/caseylam)\ **Replies:** 0\ **Last updated:** [February 5, 2025, 1:31am UTC](https://community.openastronomy.org/t/question-about-skycoord-radial-velocity-correction/1199 "2025-02-05T01:31:51Z")
I have a question about the format of the time passed into obstime in the radial\_velocity\_correction function (SkyCoord — Astropy v7.0.0) Looking at the Wright and Eastman paper which is the reference, it seems like tim… --- ## [Problems with astropy.wcs and Scamp / TPV](https://community.openastronomy.org/t/problems-with-astropy-wcs-and-scamp-tpv/401)
**Author:** [@rknop](https://community.openastronomy.org/u/rknop)\ **Replies:** 2\ **Last updated:** [February 3, 2025, 10:17am UTC](https://community.openastronomy.org/t/problems-with-astropy-wcs-and-scamp-tpv/401 "2025-02-03T10:17:23Z")
Astropy’s WCS functions are not properly transforming from RA/Dec to image coordinates. I have two images of the same field, but offset by ~10ish pixels each in x and y. If I use ds9 and tell it to align the images by… --- ## [A question on astropy logarithmic units behaviour](https://community.openastronomy.org/t/a-question-on-astropy-logarithmic-units-behaviour/1195)
**Author:** [@Bikkerion](https://community.openastronomy.org/u/Bikkerion)\ **Replies:** 4\ **Last updated:** [January 31, 2025, 3:47pm UTC](https://community.openastronomy.org/t/a-question-on-astropy-logarithmic-units-behaviour/1195 "2025-01-31T15:47:33Z")
Hi all, I’m posting this one because I’ve encountered strange behaviours in logarithmic astropy units. It looks like with the most recent version of astropy (conda create -n test\_env astropy) the issue still persists. I… [Next page](https://community.openastronomy.org/c/astropy/8.md?page=1)