Sixteen codes were added in February 2018:
AntiparticleDM: Discriminating between Majorana and Dirac Dark Matter
ARTIP: Automated Radio Telescope Image Processing Pipeline
astroplan: Observation planning package for astronomers
BHMcalc: Binary Habitability Mechanism Calculator
CMacIonize: Monte Carlo photoionisation and moving-mesh radiation hydrodynamics
collapse: Spherical-collapse model code
eqpair: Electron energy distribution calculator
FAC: Flexible Atomic Code
Glimpse: Sparsity based weak lensing mass-mapping tool
HiGal_SED_Fitter: SED fitting tools for Herschel Hi-Gal data
mrpy: Renormalized generalized gamma distribution for HMF and galaxy ensemble properties comparisons
PyOSE: Orbital sampling effect (OSE) simulator
runDM: Running couplings of Dark Matter to the Standard Model
venice: Mask utility
Verne: Earth-stopping effect for heavy dark matter
VISIBLE: VISIbility Based Line Extraction
Sixteen codes were added in December 2017:
Bitshuffle: Filter for improving compression of typed binary data
CosApps: Simulate gravitational lensing through ray tracing and shear calculation
draco: Analysis and simulation of drift scan radio data
FBEye: Analyzing Kepler light curves and validating flares
Flux Tube: Solar model
KDUtils: Kinematic Distance Utilities
LgrbWorldModel: Long-duration Gamma-Ray Burst World Model
MadDM: Computation of dark matter relic abundance
MPI_XSTAR: MPI-based parallelization of XSTAR program
Nyx: Adaptive mesh, massively-parallel, cosmological simulation code
photodynam: Photodynamical code for fitting the light curves of multiple body systems
Py-SPHViewer: Cosmological simulations using Smoothed Particle Hydrodynamics
QATS: Quasiperiodic Automated Transit Search
RODRIGUES: RATT Online Deconvolved Radio Image Generation Using Esoteric Software
SFoF: Friends-of-friends galaxy cluster detection algorithm
SgrbWorldModel: Short-duration Gamma-Ray Burst World Model
And twelve codes were added in January 2018:
BANYAN_Sigma: Bayesian classifier for members of young stellar associations
BOND: Bayesian Oxygen and Nitrogen abundance Determinations
cambmag: Magnetic Fields in CAMB
DecouplingModes: Passive modes amplitudes
DICE/ColDICE: 6D collisionless phase space hydrodynamics using a lagrangian tesselation
GABE: Grid And Bubble Evolver
Gnuastro: GNU Astronomy Utilities
hh0: Hierarchical Hubble Constant Inference
InitialConditions: Initial series solutions for perturbations in our Universe
iWander: Dynamics of interstellar wanderers
RadVel: General toolkit for modeling Radial Velocities
Stan: Statistical inference
The ASCL will receive funding for two years from NASA’s Astrophysics Data Analysis Program (ADAP) to improve the discoverability of NASA-funded astrophysics research software through the ASCL. The project will run under the direction of Dr. Peter Teuben, PI, and Alice Allen, Co-I, through the University of Maryland, College Park.
The ASCL was well-represented at the AAS 231 Hack Together Day on Friday, January 12, with Advisory Committee Chairman Peter Teuben working on two hacks, one of which hopes to provide better guidance regarding software to reviewers, dashboard developer PW Ryan also working on two hacks, both related to the ASCL and research we're conducting, and yours truly; I mostly worked on ASCL tasks that have been backlogged, such as adding preferred citation information to ASCL entries. The ASCL currently has preferred citation information listed for 25% of our entries; we will be adding this information to more records in 2018 where we can find it, though I note that many code sites do not list a preferred citation on their download sites.
For one of his hacks, Ryan grabbed all the Github links in ASCL entries, and then using a Ruby Gem that looks for licenses in Github repos, reported on the licensing information available. These results are preliminary, so please don't take them as gospel, but it appears that a whopping 34% of these codes do not have licensing information in the repo. The most popular license is MIT, which does not surprise me, as Daniel Foreman-Mackey reported in the Special Session we held at AAS 225 that MIT was the popular license across all Github repos that have licensing info.
On Thursday, January 11, the Astrophysics Source Code Library (ASCL) and Astronomical Data Group at the Flatiron Institute organized a Special Session at the 231st AAS meeting in National Harbor, MD on Astronomy Software Publishing: Community Roles and Services, the sixth in a series of software-focused sessions that the ASCL, sometimes with others, has organized at AAS meetings.
Peter Teuben from the University of Maryland and chair of the ASCL's Advisory Committee) opened the session with a few words about the use of software in research articles. He outlined the layout of the session. A talk by Matteo Cantiello set the scene on how we have reached the point where we are now. Four presentations by representatives from different journals presented their policies on software publication followed Cantiello's talk, and they were followed by presentations by representatives of others with roles in publishing software: the software author, the data editor, the ADS and the ASCL. The floor was then opened for discussion and Q&A. Teuben moderated the discussion, and at the end of it, turned the podium over to Robert Nemiroff from Michigan Technological University, and a founder of the ASCL, for a summary and closing remarks.
Presentations
Some of the main points from each presentation are summarized below; the titles of each are links to the slides used by the presenters.
Despite this, software is often not shared, resulting in a reproducibility paradox: astronomers use computation to provide precise, accurate results, but research has become less transparent with the increase in the use of computational methods. Adding external links to papers to link to software is not a reliable solution to software sharing because of link rot. Formats have changed very little in the last 400 years; despite progress both technologically and socially, the format of papers is still largely the same. He stated that astronomy now has an opportunity to rethink scientific papers as research repositories, with executable objects containing narrative, figures, data, and code.
AAS journals are interested in disclosing software in a form that is currently recognized: the research article, so now allow short papers on code that can be short, descriptive, and do not need to include scientific results. AAS formally recommends open source licensing but does not require it. AAS journals ask people to cite the software paper, as this is the currency the field cares about and also ask people to cite the code. In addition, they request people use the \software{} tag to create a software section in a paper; this is similar to the \facilities{} tag already in use. AAS Publishing continues to think about how to improve, and are introducing the concept of ‘living’ papers, which can be updated with new sections and expanded author lists, so software authors don't need to publish a new paper to give credit to software authors who have contributed to a new version of the software. Lintott encouraged those interested in living papers to contact him.
Questions arise as to how software can be peer reviewed; this would require standards for documentation, presenting how the results were obtained, making data and software available, and for reviewing the source code itself. How can referees handle this effort? Khanna pointed out that in a field as advanced as astronomy is, and already having some standards and domain resources such as archives, it’s not so much the publisher that should drive new standards, but the community itself.
She found her fellow KELT-FUN team members were an excellent focus group; they provided great feedback on the software before it was published, enabling her to add useful features to the software. Results using AstroImageJ started appearing in journals; she registered the software with the ASCL to give it a citable reference, and as usage (and support tasks) grew, she and others working on the code decided to submit a paper to the Astronomical Journal (AJ) to provide good exposure to the potential userbase for the software. This resulted in about 4K downloads of the software in the first year, and the paper is listed 4th on AJ’s most read list. Among the lessons learned in publishing AstroImageJ are to specify how your code is licensed and how it should be cited, make the source code easily accessible, and provide easy way to install and update the software.
ons for the software used in the research. Muench mentioned that he uses ten keywords in his scripts to identify software, and ends up with a surprising number of articles that do not mention code at all. He stated that part of a data editor's role to improve software and data citation is educating authors.
ADS has an interest in enabling linking so users can easily and uniquely identify the software that was used. Accomazzi covered how ADS ingestion works; for content to be considered for inclusion in ADS, it must be scholarly, related to astronomy, and published formally -- not just on a website, but following an explicit editorial process. He also discussed how citations are tracked and what ADS needs to count a citation, going through several examples of what does and does not work for citation. The bottom line for software is to cite it by using a formal citation and a unique identifier; a URL to a website or a DOI in a footnote are not captured as citations. ASCL, JOSS, and Zenodo are ways software can get a persistent identifier to use in a formal citation, and these citations can be tracked by ADS. Accomazzi also discussed how software may have several records in ADS, and that in the future, these records will be crosslinked, as will different versions of a software package so that eventually, ADS can provide cumulative metrics for all different versions of that software product, and like all citation data, this information will become publicly available through an API.Discussion
After the presentations, Teuben commented that he thought journals could do a better job in instructing referees about software, to identify when code is involved in research and insist on citations to it. He hoped the discussion would touch on this, and then opened the floor to all.
Discussion was lively and may be covered in more depth in a future post, but some of the major points were:
Teuben brought the discussion to an end and turned the floor over to Robert Nemiroff (Michigan Technological University), who briefly summarized the presentations and discussion and closed the session.
My thanks to David W. Hogg and Peter Teuben for work on developing the session, to Peter for his excellent moderating, to Robert for closing the session, and for PW Ryan for serving as scribe. My thanks to Matteo, Chris, Leslie, Ramon, Arfon, Karen, Gus, and Alberto for their excellent presentations and participation, to the Astronomical Data Group at the Flatiron Institute for partnering with the ASCL, and to the Heidelberg Institute for Theoretical Studies, the University of Maryland College Park, and Michigan Technological University for supporting the ASCL.
THURSDAY, 11 JANUARY 2018
Special Session: Astronomy Software Publishing: Community Roles and Services
10:00 am – 11:30 am
National Harbor 2
The Astrophysics Source Code Library (ASCL) and Astronomical Data Group at the Flatiron Institute organized a Special Session at the 231st AAS meeting in National Harbor, MD on Astronomy Software Publishing: Community Roles and Services. Click on a talk's title to download its slides.
Matteo Cantiello (Flatiron Institute), The Evolution of Software Publication in Astronomy
Chris Lintott (AAS Journals), Software papers and citation in the AAS Journals
Leslie J. Sage (Nature), Software policies and guidelines at Nature
Ramon Khanna (Springer), SpringerNature data and software policies for astrophysics journals
Arfon M. Smith (STScI/JOSS), Journal of Open Source Software (JOSS): Design and first-year review
Karen Collins (Center for Astrophysics), Lessons Learned through the Development and Publication of AstroImageJ
August Muench (AAS Journals), The roles of the AAS Journals' Data Editors
Alberto Accomazzi (NASA Astrophysics Data System), The role of the ADS in software discovery and citation
Alice Allen (ASCL/UMD), The Astrophysics Source Code Library: Supporting software publication and citation

Astronomers use software for their research, but how many of the codes they use are available as source code? We examined a sample of 166 papers from 2015 for clearly identified software use, then searched for source code for the software packages mentioned in these research papers. We categorized the software to indicate whether source code is available for download and whether there are restrictions to accessing it, and if source code was not available, whether some other form of the software, such as a binary, was. Over 40% of the source code for the software used in our sample was not available for download.
As URLs have often been used as proxy citations for software, we also 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 still accessible in September and October, 2017.
P. Wesley Ryan, Astrophysics Source Code Library
Alice Allen, Astrophysics Source Code Library/University of Maryland
Peter Teuben, University of Maryland

The Astrophysics Source Code Library (ASCL, ascl.net) was founded in 1999 by Robert Nemiroff and John Wallin. ASCL editors seek both new and old peer-reviewed papers that describe methods or experiments that involve the development or use of source code, and add entries for the found codes to the library. Software authors can submit their codes to the ASCL as well. This ensures a comprehensive listing covering a significant number of the astrophysics source codes used in peer-reviewed studies. The ASCL is indexed by both NASA’s Astrophysics Data System (ADS) and Web of Science, making software used in research more discoverable. This presentation covers the growth in the ASCL’s number of entries, the number of citations to its entries, and in which journals those citations appear.
Alice Allen, Astrophysics Source Code Library/University of Maryland
G. Bruce Berriman, Caltech/IPAC-NExScI
Kimberly DuPrie, Space Telescope Science Institute/Astrophysics Source Code Library
Jessica Mink, Smithsonian Astrophysical Observatory
Robert Nemiroff, Michigan Technological University
P.W. Ryan, Astrophysics Source Code Library
Judy Schmidt, Astrophysics Source Code Library
Lior Shamir, Lawrence Technological University
Keith Shortridge, Knave and Varlet
Peter Teuben, University of Maryland
John Wallin, Middle Tennessee State University
Rein H. Warmels, European Southern Observatory
It's AAS meeting time, and that means a busy busy week! There are some of the ASCL's activities at this meeting; we hope to see you at our posters and in the Special Session!
Poster 150.10: The Astrophysics Source Code Library by the numbers
Tuesday, January 09, Prince Georges Exhibit Hall
Abstract: The Astrophysics Source Code Library (ASCL, ascl.net) was founded in 1999 by Robert Nemiroff and John Wallin. ASCL editors seek both new and old peer-reviewed papers that describe methods or experiments that involve the development or use of source code, and add entries for the found codes to the library. Software authors can submit their codes to the ASCL as well. This ensures a comprehensive listing covering a significant number of the astrophysics source codes used in peer-reviewed studies. The ASCL is indexed by both NASA’s Astrophysics Data System (ADS) and Web of Science, making software used in research more discoverable. This presentation covers the growth in the ASCL’s number of entries, the number of citations to its entries, and in which journals those citations appear. It also discusses what changes have been made to the ASCL recently, and what its plans are for the future.
Poster 150.28: Schroedinger’s code: Source code availability and transparency in astrophysics
Tuesday, January 09, Prince Georges Exhibit Hall
Abstract: Astronomers use software for their research, but how many of the codes they use are available as source code? We examined a sample of 166 papers from 2015 for clearly identified software use, then searched for source code for the software packages mentioned in these research papers. We categorized the software to indicate whether source code is available for download and whether there are restrictions to accessing it, and if source code was not available, whether some other form of the software, such as a binary, was. Over 40% of the source code for the software used in our sample was not available for download.
As URLs have often been used as proxy citations for software, we also 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 still accessible in September and October, 2017.
Special Session: Astronomy Software Publishing: Community Roles and Services
Thursday, January 11, 10:00 AM - 11:30 AM; National Harbor 2
Organizers: Astrophysics Source Code Library (ASCL)/Astronomical Data Group at the Flatiron Institute
The importance of software to astronomy research is well-established, and excellent arguments to reveal these computational methods to support the research record have been advanced and much discussed in recent years. But what avenues are open to software authors to publish their codes, and what roles and services exist in the community to support their efforts? This session, organized by the Astrophysics Source Code Library (ASCL) and Astronomical Data Group at the Flatiron Institute, answers that question. It builds on previous AAS special sessions and brings together a panel of experts to present on the various avenues for publishing codes and the pros and cons of these avenues, the roles of authors, data editors, and publication indexers in software publication, the benefits of publication to authors and the discipline, and efforts of related community projects to improve aspects of software publication. After the presentations, the floor will be open for discussion and questions.
The topics and panelists are:
Introductory remarks, Peter Teuben (University of Maryland)
The evolution of software publication in astronomy, Matteo Cantiello (Flatiron Institute, Center for Computational Astrophysics/Princeton University)
Software papers and citation in the AAS journals, Chris Lintott (AAS Journals/University of Oxford)
Software policies and guidelines at Nature, Leslie J. Sage (Physical Sciences, Nature)
SpringerNature data and software policies for astrophysics journals, Ramon Khanna (Astronomy, Springer)
Journal of Open Source Software (JOSS): design and first-year review, Arfon M. Smith (Space Telescope Science Institute)
Lessons learned through the development and publication of AstroImageJ, Karen Collins (Harvard-Smithsonian Center for Astrophysics)
The roles of the AAS Journals' Data Editors, August Muench (Journals Division, AAS)
The role of the ADS in software discovery and citation, Alberto Accomazzi (Smithsonian Astrophysical Observatory)
The Astrophysics Source Code Library: Supporting software publication and citation, Alice Allen (ASCL/University of Maryland)
Open discussion and Q&A, Moderated by Peter Teuben (University of Maryland)
Summary and closing remarks, Robert J. Nemiroff (Michigan Technological University)
If you are going to the AAS meeting in National Harbor next month, you might consider taking some time to visit the National Gallery of Art for a rare opportunity to view two paintings well-known to Astronomy Picture of the Day (APOD) fans: Vermeer's luminous The Astronomer and The Geographer. These paintings, owned by the Louvre and the Städelsches Kunstinstitut respectively, are part of the wonderful Vermeer and the Masters of Genre Painting: Inspiration and Rivalry exhibit which runs through January 21, 2018 in the West building of the Gallery.
Why are these two paintings well-known to APOD fans? A mashup of these two paintings appeared on APOD's first birthday on June 16, 1996; note the introduction of a Hubble image for the painting on the wall:

On APOD's 5th birthday, a new composite of these paintings appeared:

Apparently, a tradition was born, and APOD fans started contributing their own takes on these famous images, as seen below in the 10th birthday image, created by Richard Taillet (Univ. de Savoie, LAPTH, LPNHE) and including a few objects that Vermeer's astronomer never had the opportunity to view.

The next landmark APOD birthdays featured the image that appeared for the 10th birthday, but with a twist: it was pixelated by APOD fan Rob Stevenson using APOD thumbnail images. The image below does not do this justice, so please click through to the larger image housed on the APOD site to see whether you can find your favorite APOD amongst the ones making up this image.

To get back to the art exhibit, Vermeer is not the only painter featured in Genre Painting show, nor is his the only astronomer there. The Geographer and The Astronomer appear on one wall with Gerrit Dou's Astronomer by Candlelight, owned by the Getty Museum, between them. Paintings by other Dutch artists, including Gerard ter Borch, Caspar Netscher, Pieter de Hooch, and Jan Steen, are also on display. So many Dutch treats! It's a lovely exhibit and well worth finding your way to the National Gallery.
You will not have to go to the National Gallery of Art to see the APOD editors, however! Jerry Bonnell and Robert Nemiroff are giving a public talk at the AAS meeting at National Harbor; The Year's Best Astronomy Images will be held on Tuesday, January 9 starting at 7:00 pm in the Gaylord's Maryland Ballroom D.