Category Archives: presentations

ASCL poster at AAS235

Abstract: Software citation is good for research transparency and reproducibility, and maybe, if you work it right, for your CV, too. You can get credit and recognition through citations for your code! This presentation highlights several powerful methods for increasing the probability that use of your research software will be cited, and cited correctly. The presentation covers how to create codemeta.json and CITATION.cff automagically from Astrophysics Source Code Library (ASCL entries, edit, and use these files, the value of including such files on your code site(s), and efforts underway in astronomy and other fields to improve software citation and credit.

Authors: A. Allen1,2, R. Nemiroff3, P. Ryan1, J. Schmidt1, P. Teuben2
1Astrophysics Source Code Library
2Astronomy Department, University of Maryland, College Park, MD
3Michigan Technological University, Houghton, MI

Download (PDF)

The ASCL at AAS 235

The ASCL is participating in the American Astronomical Society (AAS) meeting that started yesterday in Honolulu, Hawai’i. We have two events, both on Sunday, January 5:

Best ways to let others know how to cite your research software
January 5; Poster 109.12
Software citation is good for research transparency and reproducibility, and maybe, if you work it right, for your CV, too. You can get credit and recognition through citations for your code! This presentation highlights several powerful methods for increasing the probability that use of your research software will be cited, and cited correctly. The presentation covers how to create codemeta.json and CITATION.cff automagically from Astrophysics Source Code Library (ASCL entries, edit, and use these files, the value of including such files on your code site(s), and efforts underway in astronomy and other fields to improve software citation and credit.

The Future and Future Governance of the Astrophysics Source Code Library
January 5, 2:00 PM – 3:30 PM; HCC – Room 301B
Over the past ten years, the Astrophysics Source Code Library (ASCL, has grown from a small repository holding about 40 codes with hand-coded HTML pages maintained by one person to a resource with citable entries on over 2000 codes with a modern database structure that is user- and editor-friendly maintained by a small group of volunteers. With its 20th anniversary now behind it, it’s time to look at the resource and its governance and management. Does its current structure best serve the astro community? What changes would you like to see to its governance? We don’t know the answers to these and other questions! Please join us for an open discussion on the resource and what a new governance model for the ASCL might be.

ASCL research poster at ADASS XXIV

This presentation covers research on software authorship and citation, which we carried out between July and September 2019. We examined codes authored by three or fewer people (“short author list” codes) and codes authored by institutional teams, to determine how many codes in the ASCL can be attributed to one of these categories. Utilizing ADS data, we measured the number of citations per authorship category. We carried out further research to determine whether we could infer software usage and code usage statistics from the number of citations to code description papers. Our research shows that citations to code description papers are not a reliable proxy for software usage.

P. Wesley Ryan, Astrophysics Source Code Library

Download poster (PDF)

Understanding data: Visualisation, machine learning, and reproducibility

The ASCL has once again partnered with others on a Special Session at EWASS. This year’s Special Session (SS34) is titled Understanding data: Visualisation, machine learning, and reproducibility, and will be held on Tuesday, 25 June, in Room 3. Not at EWASS? Follow the session on Twitter at #ewass19ss34.

Full information, including abstracts for the presentations listed below, can be found in the detailed interactive program; look for the sessions in yellow and labeled SS34a, SS34b, and SS34c.

Tuesday, 25 June, 9:00 in Room 3, chaired by Rein Warmels
Reproducibility in computer-aided research by Konrad Hinsen
Publishing associated data: Challenges & opportunities by Pierre Ocvirk
FAIR data in astronomy by Mark Allen
Template for reproducible, shareable & achievable research by Mohammad Akhlaghi
These talks are followed by an open discussion moderated by David Valls-Gabaud.

Tuesday, 25 June, 14:30 in Room 3, chaired by Amruta Jaodand
High-performance machine learning in Astrophysics by Simon Portegies Zwart
Machine learning for the SKA by Anna Scaife
SuperNNova: Open-source, deep learning photometric time-series classifier by Anais Möller
Transfer learning for radio galaxy classification by Hongming Tang
Unsupervised classification of galaxy spectra and interpretability by Didier Fraix-burnet

Tuesday, 25 June, 16:30 in Room 3, chaired by John Wenskovitch
Visual Analytics of Data in Astronomy by Johanna Schmidt
Visual analytics algorithms for multidimensional astronomical data by Dany Vohl
Pulsar to Person (P2P): Data Visualization & Sonification to Experience the Universe by John Wenskovitch
Lightning talks for e-Posters
These talks are followed by an open discussion moderated by the session chair.

This Special Session was organized by:
Rachael Ainsworth (UManchester)
Mohammad Akhlaghi (Instituto De Astrofísica De Canarias)
Amruta Jaodand (ASTRON)
David Valls-Gabaud (Observatoire de Paris)
Rein Warmels (ESO)
John Wenskovitch (Virginia Tech)
Alice Allen (ASCL/UMD)

Open Digital Infrastructure in Astrophysics

I spent two days last week at the Open Digital Infrastructure in Astrophysics meeting at the Kavli Institute for Theoretical Physics (KITP) at UC Santa Barbara. This meeting featured presentations on open-knowledge digital infrastructure projects, the communities around them, their metrics for success, funding, diversity efforts, and plans for sustainability. Yeah, we’re talking code, a lot of code, and code projects, too, from AstroPy to yt, and data, and efforts that support openness and research transparency.

Open data presentations were given on:

STScI data, which includes JWST, Hubble, and PanSTARRS data, and the discovery and analysis software for these archives, by Arfon Smith
SDSS Data Infrastructure, by Joel Brownstein
LSST Transients data, by Federica Bianco
Open gravitational wave data and software tools for these data, by Duncan Brown

These software projects were represented at the meeting:

photograph of the Kavli Institute for Theoretical PhysicsAstropy, by Kelle Cruz
ATHENA++, by Jim Stone
Einstein Toolkit, by Philipp Mösta
emcee, by Daniel Foreman-Mackey
GYRE, by Rich Townsend
JETFIT, by Andrew Macfadyen
MESA Project, by Frank Timmes
TOM Toolkit and the AEON Network, by Rachel Street
yt, by Matt Turk

Other open digital resources presented were:

Journal of Open Source Software, by Arfon Smith
R astrostatistics, by Gwendolyn Eadie
Astrophysics Source Code Library, by yours truly

The meeting hashtag was #OpenAstroInfra, and many of the presentations were live tweeted. They were also video recorded and the podcasts are available on the KITP media page for the meeting, as are most of the slide decks. Participants of the co-located “Better Stars, Better Planets: Exploiting the Stellar-Exoplanetary Synergy” and “The New Era of Gravitational-Wave Physics and Astrophysics” programs were encouraged to attend, and we had a raven or two trying to have lunch with us as well.

Each of the presentations had about 15 minutes devoted to questions and discussion about the project highlighted. In two of these discussion sessions, the presenters were asked whether they were concerned about “improper use” of a code; sometimes people who are not well-schooled in the theory or science underlying a software package will use the code incorrectly, arriving at results that are dodgy, or downright wrong, and in a few cases (I know of only one), have then claimed the software is in error. This fear has been given as the reason some software authors do not release their code. I was cheering in my head with Jim Stone’s response to this question the first time it came up; he stated that there is so much benefit to making the code available that a potential improper use should not stop release. (YES!!!) He further went on to say, as did others in the room, that science will correct the record (YES!!!!!). I could not agree more with these replies, and it was great to hear these sentiments from others.

This was my first visit to KITP, and what a wonderful introduction to the institution it was! So many excellent projects, and so much exciting work being done in the open! My thanks to organizers Frank Timmes, Lars Bildsten, and Rich Townsend for inviting the ASCL to participate, and to the Sloan and Ford Foundations for funding the meeting.

ASCL presentation slides

Research Data Alliance Plenary 13 presentation

The ASCL is participating in the Research Data Alliance (RDA) meeting currently underway in Philadelphia, PA. The Plenary 13 meeting motto is “With Data Comes Responsibility.” Indeed! Among the sessions of special interest for software folks was yesterday’s Interest Group meeting on Software Source Code and today’s first meeting of a new Working Group on Software Source Code Identification. The Working Group is led by Roberto Di Cosmo, who is a founder of Software Heritage, Martin Fenner from DataCite, and Daniel Katz from the University of Illinois. This initial meeting is titled “Identifying, referencing and citing the source code of research software: a state of the art.” The ASCL is doing a short presentation that focuses on a few of our practices, how we do them, and the rationale for them; this includes what we do when we process a submission, what metadata for software we do and don’t have and why, and some of our curation practices. Our slides for this presentation are available below.

Photograph of Alice presenting a slide

Photo courtesy of @StephvandeSandt

Our attendance at this meeting was made possible with support from Software Heritage; our thanks to that organization!

Slides (PDF)

A visit to NASA’s Goddard Space Flight Center

Photo showing slide of new journals friendly to astro computing articles started since 2012

At the podium

Although I was born in Washington, DC and have spent most of my life in its Maryland suburbs, yesterday was my first time on the Goddard campus (aside from its Visitor Center, which I’ve been to many times), this despite having two family members and many friends who used to1 or do work there. I was excited! And I had a great reason for going: I was presenting a talk to the Astrophysics Science Division titled “Make your research software famous! (or at least discoverable).” The talk, broadcast on a NASA UStream channel and recorded for future viewing,2 covered a bit about our research on source code availability in astronomy, and also covered our current project to make NASA astro research software more discoverable, what the Astrophysics Source Code Library is and how it improves research transparency, software citation, and recent changes in publishing with regard to software that, combined with other changes in the community and science in general, make it easier than ever before to make one’s astro research software discoverable. The slides I presented are available for download (PDF), and links to different resources, journals, and organizations that I mentioned in the talk are also available.

Kristin Rutkowski, along with Tess Jaffe and Alex Reustle, hosted my visit to GSFC; I had met both Kristin and Tess at last year’s ADASS conference in College Park, where we had our first conversation about my visiting the site to talk about the ASCL. Yesterday’s audience was great; they were involved and asked a lot of excellent questions, about copyright, code authors not receiving credit for the software they write, how we handle dead links, mutable author lists, NASA policies regarding software release, and how the ASCL is funded. Some of the questions came from people attending remotely and were asked online; Alex made sure these were covered, too. Alex is also involved in making the video of the talk available online, and when it is available, I’ll update this post with its link.

Photo of NASA's Space Environment Simulator

Space Environment Simulator

After my presentation, Kristin and Tess took me to see some of the NASA labs and equipment, including the Space Environment Simulator Facility, the JWST/OTIS Vibration Test System, the currently out-of-service High Capacity Centrifuge, and the Acoustic Test Cell. We went through doors marked “Authorized Personnel Only”!! This is one of the perqs of working on the ASCL — I become “Authorized Personnel” when visiting telescopes and labs and such, which, to me, is very cool and exciting! Sure, it’s only for a few minutes and always in the company of others who have far more business being there than I do, but still: very cool and exciting!! After looking at these labs and equipment, Kristin and I said goodbye to Tess, and then drove over to see dinosaur footprints that had been found on the Goddard campus. (Could a visit anywhere be any cooler?!?!)

Dinosaur and small mammal tracks

Science science everywhere! I had a great time at Goddard, and thank Alex and Tess and especially Kristin for hosting my visit!








1 Happy retirement day, Janie!
2 No, that’s not nerve-wracking at all, so long as one doesn’t think about it.

Resources mentioned in NASA GSFC presentation on making research software more discoverable

Presentation slides (PDF)


Journal of Open Source Software (JORS)

Astronomy and Computing (A&C)

Computational Astrophysics and Cosmology (ComAC)


Journal of Open Source Software (JOSS)

Research Notes of the AAS

Change leaders and guidelines

Force11/Force11 Software Citation Principles


Working toward Sustainable Software for Science: Practice and Experiences (WSSSPE)

FAIR principles

Social coding sites and archival services





Other resources


arXiv/arXiv Next Generation


Research poster at AAS 233

URLs have often been used as proxy citations for software and data. We extracted URLs from one journal’s 2015 research articles, removed those from certain long-term reliable domains, and tested the remainder to determine what percentage of these URLs were accessible in September and October 2017. We repeated this test a year later to determine what percentage of these links were still accessible. We will present what we learned about URL accessibility in astronomy.

P. Wesley Ryan, Astrophysics Source Code Library

Download poster

ASCL poster at AAS #233

Software is the most used instrument in astronomy, and organizations such as NASA and the Heidelberg Institute for Theoretical Physics (HITS) fund, develop, and release research software. NASA, for example, has created sites such as and to share its software with the world, but how easy is it to see what NASA has? Until recently, searching NASA’s Astrophysics Data System (ADS) for NASA’s astronomy software has not been fruitful; NASA has funded the Astrophysics Source Code Library (ASCL to improve the discoverability of these codes. The ASCL, now celebrating its 20th anniversary, is a free online registry of software used in astronomy research and is indexed by ADS, Web of Science, and other resources. Adding NASA and HITS astronomy research codes to the ASCL with appropriate tags enables finding this software easily not only in the ASCL but also in ADS and other services that index the ASCL. This poster presentation covers the changes the ASCL has made to enable discovery of NASA software in ADS and the results of this work.

Alice Allen, Astrophysics Source Code Library/University of Maryland, College Park
Peter Teuben, University of Maryland, College Park
Judy Schmidt, Astrophysics Source Code Library
Robert Nemiroff, Michigan Technological University

Download poster