Twenty-five codes were added to the ASCL in August:

AMOEBA: Automated Gaussian decomposition
AUM: A Unified Modeling scheme for galaxy abundance, galaxy clustering and galaxy-galaxy lensing
AutoProf: Automatic Isophotal solutions for galaxy images
BOSS-Without-Windows: Window-free analysis of the BOSS DR12 power spectrum and bispectrum
caesar-rest: Web service for the caesar source extractor

CatBoost: High performance gradient boosting on decision trees library
catwoman: Transit modeling Python package for asymmetric light curves
Chemulator: Thermochemical emulator for hydrodynamical modeling
CMC-COSMIC: Cluster Monte Carlo code
Cosmic-CoNN: Cosmic ray detection toolkit

COSMIC: Compact Object Synthesis and Monte Carlo Investigation Code
DBSP_DRP: DBSP Data Reduction Pipeline
ELISa: Eclipsing binaries Learning Interactive System
ExoPlaSim: Exoplanet climate simulator
FIREFLY: Chi-squared minimization full spectral fitting code

HRK: HII Region Kinematics
iminuit: Jupyter-friendly Python interface for C++ MINUIT2
MAPS: Multi-frequency Angular Power Spectrum estimator
millennium-tap-query: Python tool to query the Millennium Simulation UWS/TAP client
NRDD_constraints: Dark Matter interaction with the Standard Model exclusion plot calculator

PIPS: Period detection and Identification Pipeline Suite
SORA: Stellar Occultation Reduction Analysis
StelNet: Stellar mass and age predictor
viper: Velocity and IP EstimatoR
WaldoInSky: Anomaly detection algorithms for time-domain astronomy

Thirty codes were added to the ASCL in July:

AlignBandColors: Inter-color-band image alignment tool
ART: A Reconstruction Tool
Balrog: Astronomical image simulation
Chem-I-Calc: Chemical Information Calculator
cosmic_variance: Cosmic variance calculator

FoF-Halo-finder: Halo location and size
GUBAS: General Use Binary Asteroid Simulator
HERMES: High-Energy Radiative MESsengers
K2-CPM: Causal Pixel Model for K2 data
K2mosaic: Mosaic Kepler pixel data

Kd-match: Correspondences of objects between two catalogs through pattern matching
KeplerPORTS: Kepler Planet Occurrence Rate Tools
light-curve: Light curve analysis toolbox
MCPM: Modified CPM method
nimbus: A Bayesian inference framework to constrain kilonova models

PHL: Persistent_Homology_LSS
PlaSim: Planet Simulator
PMN-body: Particle Mesh N-body code
PyCactus: Post-processing tools for Cactus computational toolkit simulation data
PyROA: Modeling quasar light curves

ReionYuga: Epoch of Reionization neutral Hydrogen field generator
RePrimAnd: Recovery of Primitives And EOS framework
ROA: Running Optimal Average
shapelens: Astronomical image analysis and shape estimation framework
shear-stacking: Stacked shear profiles and tests based upon them

Skylens++: Simulation package for optical astronomical observations
Skymapper: Mapping astronomical survey data on the sky
snmachine: Photometric supernova classification
SpArcFiRe: SPiral ARC FInder and REporter
TRINITY: Dark matter halos, galaxies and supermassive black holes empirical model

Forty codes were added to the ASCL in June:

ATES: ATmospheric EScape
atmos: Coupled climate–photochemistry model
aztekas: GRHD numerical code
baofit: Fit cosmological data to measure baryon acoustic oscillations
BiFFT: Fast estimation of the bispectrum

BiHalofit: Fitting formula of non-linear matter bispectrum
CalPriorSNIa: Effective calibration prior on the absolute magnitude of Type Ia supernovae
CoMover: Bayesian probability of co-moving stars
crowdsource: Crowded field photometry pipeline
DarkSirensStat: Measuring modified GW propagation and the Hubble parameter

DM_statistics: Statistics of the cosmological dispersion measure (DM)
dopmap: Fast Doppler mapping program
ehtplot: Plotting functions for the Event Horizon Telescope
EMBERS: Experimental Measurement of BEam Responses with Satellites
FRBSTATS: A web-based platform for visualization of fast radio burst properties

GLEMuR: GPU-based Lagrangian mimEtic Magnetic Relaxation
IRAGNSEP: Spectral energy distribution fitting code
Kadath: Spectral solver
Katu: Interaction of particles in plasma simulator
KOBE: Kepler Observes Bern Exoplanets

Lemon: Linear integral Equations’ Monte carlo solver based On the Neumann solution
MakeCloud: Turbulent GMC initial conditions for GIZMO
Maneage: Managing data lineage
Marvin: Data access and visualization for MaNGA
ModeChord: Primordial scalar and tensor power spectra solver

MultiModeCode: Numerical exploration of multifield inflation models
picca: Package for Igm Cosmological-Correlations Analyses
PORTA: POlarized Radiative TrAnsfer
PyDoppler: Wrapper for Doppler tomography software
Pyshellspec: Binary systems with circumstellar matter

QuasarNET: CNN for redshifting and classification of astrophysical spectra
RedPipe: Reduction Pipeline
redvsblue: Quasar and emission line redshift fitting
simple_reg_dem: Differential Emission Measures in the solar corona
simqso: Simulated quasar spectra generator

so_noise_models: Simons Observatory N(ell) noise models
StarcNet: Convolutional neural network for classifying galaxy images into morphological classes
STaRS: Sejong Radiative Transfer through Raman and Rayleigh Scattering with atomic hydrogen
ztf-viewer: SNAD ZTF data releases object viewer
ZWAD: ZTF anomaly detection

Twenty-two codes were added to the ASCL in May:

ATARRI: A TESS Archive RR Lyrae Classifier
BHPToolkit: Black Hole Perturbation Toolkit
BlackBOX: BlackGEM and MeerLICHT image reduction software
ClaRAN: Classifying Radio sources Automatically with Neural networks
COMPAS: Rapid binary population synthesis code

CUDAHM: MCMC sampling of hierarchical models with GPUs
encore: Efficient isotropic 2-, 3-, 4-, 5- and 6-point correlation functions
Kepler’s Goat Herd: Solving Kepler’s equation via contour integration
MCALF: Velocity information from spectral imaging observations
MeerCRAB: Transient classifier using a deep learning model

orvara: Orbits from Radial Velocity, Absolute, and/or Relative Astrometry
PAP: PHANGS-ALMA pipeline
PDM2: Phase Dispersion Minimization
PFITS: Spectra data reduction
Pyrat Bay: Python Radiative Transfer in a Bayesian framework

PyTorchDIA: Difference Image Analysis tool
RandomQuintessence: Integrate the Klein-Gordon and Friedmann equations with random initial conditions
SISPO: Imaging simulator for small solar system body missions
SpheCow: Galaxy and dark matter halo dynamical properties
TesseRACt: Tessellation-based Recovery of Amorphous halo Concentrations

The Sequencer: Detect one-dimensional sequences in complex datasets
ZOGY: Python implementation of proper image subtraction

Thirty-one codes were added to the ASCL in April:

Bagpipes: Bayesian Analysis of Galaxies for Physical Inference and Parameter EStimation
cmblensplus: Cosmic microwave background tools
CTR: Coronal Temperature Reconstruction
dense_basis: Dense Basis SED fitting

EPIC5: Lindblad orbits in ovally perturbed potentials
Freeture: Free software to capTure meteors
GAMMA: Relativistic hydro and local cooling on a moving mesh
GGchem: Fast thermo-chemical equilibrium code

globalemu: Global (sky-averaged) 21-cm signal emulation
hera_opm: The HERA Online Processing Module
Hilal-Obs: Authentication agorithm for new moon visibility report
LaFuLi: NASA Langley Fu-Liou radiative transfer code

LAPACK: Linear Algebra PACKage
Librarian: The HERA Librarian
linemake: Line list generator
lofti_gaiaDR2: Orbit fitting with Gaia astrometry

Mo’Astro: MongoDB framework for observational astronomy
OpacityTool: Dust opacities for disk modeling
OpTool: Command-line driven tool for creating complex dust opacities
pfits: PSRFITS-format data file processor

Posidonius: N-Body simulator for planetary and/or binary systems
PyBird: Python code for biased tracers in redshift space
RadioFisher: Fisher forecasting for 21cm intensity mapping and spectroscopic galaxy surveys
RJObject: Reversible Jump Objects

Skye: Equation of state for fully ionized matter
Skyoffset: Sky offset optimization and mosaicing toolkit
SpaceHub: High precision few-body and large scale N-body simulations
Spectractor: Spectrum extraction tool for slitless spectrophotometry

SpectRes: Simple spectral resampling
SSSpaNG: Stellar Spectra as Sparse Non-Gaussian Processes
TES: Terrestrial Exoplanet Simulator

Thirty-one codes were added to the ASCL in March:

21cmDeepLearning: Matter density map extractor
ARTIS: 3D Monte Carlo radiative transfer code for supernovae
Astro-Fix: Correcting astronomical bad pixels in Python
AstroNet-Triage: Neural network for TESS light curve triage

AstroNet-Vetting: Neural network for TESS light curve vetting
Carsus: Atomic database for astronomy
CARTA: Cube Analysis and Rendering Tool for Astronomy
CRIME: Cosmological Realizations for Intensity Mapping Experiments

DarkEmulator: Cosmological emulation code for halo clustering statistics
DIAPHANE: Library for radiation and neutrino transport in hydrodynamical simulations
DRAKE: Relic density in concrete models prediction
GalacticDNSMass: Bayesian inference determination of mass distribution of Galactic double neutron stars

GalLenspy: Reconstruction of mass profile in disc-like galaxies from the gravitational lensing effect
ggm: Gaussian gradient magnitude filtering of astronomical images
hfs_fit: Atomic emission spectral line hyperfine structure fitting
LPF: Real-time detection of transient sources in radio data streams

nestle: Nested sampling algorithms for evaluating Bayesian evidence
PION: Computational fluid-dynamics package for astrophysics
Pyedra: Python implementation for asteroid phase curve fitting
PyPion: Post-processing code for PION simulation data

QuickCBC: Rapid and reliable inference for binary mergers
RAiSERed: Analytic AGN model based code for radio-frequency redshifts
redshifts: Spectroscopic redshifts search tool
satcand: Orbital stability and tidal migration constraints for KOI exomoon candidates

schNell: Fast calculation of N_ell for GW anisotropies
Silo: Saving scientific data to binary disk files
spalipy: Detection-based astronomical image registration
SparseBLS: Box-Fitting Least Squares implementation for sparse data

SUPERNU: Radiative transfer code for explosive outflows using Monte Carlo methods
TFF: Template Fourier Fitting
TransitFit: Exoplanet transit fitting package for multi-telescope datasets

Thirty codes were added to the ASCL in February:

BALRoGO: Bayesian Astrometric Likelihood Recovery of Galactic Objects
binaryoffset: Detecting and correcting the binary offset effect in CCDs
CMasher: Scientific colormaps for making accessible, informative plots
DaMaSCUS-SUN: Dark Matter Simulation Code for Underground Scatterings – Sun Edition
EqTide: Equilibrium Tide calculations

extinction: Dust extinction laws
ForwardDiff: Forward mode automatic differentiation for Julia
GalRotpy: Parametrize the rotation curve and gravitational potential of disk-like galaxies
GLEAM: Galaxy Line Emission and Absorption Modeling
hardCORE: Exoplanet core radius fractions calculator

HUAYNO: Hierarchically split-Up AstrophYsical N-body sOlver N-body code
lensingGW: Lensing of gravitational waves
Lightbeam: Simulate light through weakly-guiding waveguides
mirkwood: SED modeling using machine learning
MOSAIC: Multipole operator generator for Fast Multipole Method operators

MST: Minimum Spanning Tree algorithm for identifying large-scale filaments
Multi_CLASS: Cross-tracer angular power spectra of number counts using CLASS
MUSE-PSFR: PSF reconstruction for MUSE WFM-AO mode
nway: Bayesian cross-matching of astronomical catalogs
OPUS: Interoperable access to analysis and simulation codes

Piff: PSFs In the Full FOV
Pixell: Rectangular pixel map manipulation and harmonic analysis library
polgraw-allsky: All-sky almost-monochromatic gravitational-wave pipeline
PyAutoFit: Classy probabilistic programming
PyFstat: Continuous gravitational-wave data analysis

RASSINE: Normalizing 1D stellar spectra
spinOS: SPectroscopic and INterferometric Orbital Solution finder
ThumbStack: Map and profile stacking pipeline
viscm: Analyzing colormaps and creating new colormaps
X-PSI: X-ray Pulse Simulation and Inference

Eighteen codes were added to the ASCL in January:

3LPT-init: Initial conditions with third-order Lagrangian perturbation for cosmological N-body simulations
apogee: Tools for APOGEE data
Avocado: Photometric classification of astronomical transients and variables with biased spectroscopic samples
BAYES-LOSVD: Bayesian framework for non-parametric extraction of the LOSVD
cFS: core Flight System

Curvit: Create light curves from UVIT data
DarpanX: X-ray reflectivity of multilayer mirrors
Eigentools: Tools for studying linear eigenvalue problems
EphemMatch: Ephemeris matching of DR25 TCEs, KOIs, and EBs for false positive identification
Mask galaxy: Machine learning pipeline for morphological segmentation of galaxies

Nigraha: Find and evaluate planet candidates from TESS light curves
Octo-Tiger: HPX parallelized 3-D hydrodynamic code for stellar mergers
ptemcee: A parallel-tempered version of emcee
pyUPMASK: Unsupervised clustering method for stellar clusters
PyXspec: Python interface to XSPEC spectral-fitting program

radiowinds: Radio Emission from Stellar Winds
stratsi: Stratified streaming instability
whereistheplanet: Predicting positions of directly imaged companions

Twenty-six codes were added to the ASCL in December:

BinaryStarSolver: Orbital elements of binary stars solver
BlackHawk: Black hole evaporation calculator
dolphin: Automated pipeline for lens modeling
DRAGraces: Reduction pipeline for GRACES spectra

EinsteinPy: General Relativity and gravitational physics problems solver
EOS: Equation of State for planetary impacts
getsf: Multi-scale, multi-wavelength sources and filaments extraction
HCGrid: Mapping non-uniform radio astronomy data onto a uniformly distributed grid

HydroCode1D: 1D finite volume code
LALSuite: LIGO Scientific Collaboration Algorithm Library Suite
LIFELINE: LIne proFiles in massivE coLliding wInd biNariEs
MADLens: Differentiable lensing simulator

Magritte: 3D radiative transfer library
MLC_ELGs: Machine Learning Classifiers for intermediate redshift Emission Line Galaxies
NSCG: NOIRLab Source Catalog Generator
Pomegranate: Probabilistic model builder

PyXel: Astronomical X-ray imaging data modeling
Robovetter: Automatic vetting of Threshold Crossing Events (TCEs)
seaborn: Statistical data visualization
sedop: Optimize discrete versions of common SEDs

Sengi: Interactive viewer for spectral outputs from stellar population synthesis models
SimCADO: Observations simulator for infrared telescopes and instruments
Skye: Excess clustering of transit times detection
SLIT: Sparse Lens Inversion Technique

SWIGLAL: Access LALSuite libraries with Python and Octave scripts
TRAN_K2: Planetary transit search

Thirty codes were added to the ASCL in November 2020:

ACStools: Python tools for Hubble Space Telescope Advanced Camera for Surveys data
AdaMet: Adaptive Metropolis for Bayesian analysis
ARES: Accelerated Reionization Era Simulations
CAPTURE: Interferometric pipeline for image creation from GMRT data
Clustering: Code for clustering single pulse events

CWITools: Tools for Cosmic Web Imager data
DarkBit: Dark matter constraints calculator
DarkCapPy: Dark Matter Capture and Annihilation
DDCalc: Dark matter direct detection phenomenology package
DeepShadows: Finding low-surface-brightness galaxies in survey images

DYNAMITE: DYnamics, Age and Metallicity Indicators Tracing Evolution
EvapMass: Minimum mass of planets predictor
frbcat: Fast Radio Burst CATalog querying package
GoFish: Molecular line detections in protoplanetary disks
GOTHIC : Double nuclei galaxy detector

GPCAL: Instrumental polarization calibration in VLBI data
HaloGen: Modular halo model code
HSTCosmicrays: Analyzing cosmic rays in HST calibration data
Kalkayotl: Inferring distances to stellar clusters from Gaia parallaxes
kīauhōkū: Stellar model grid interpolation

MCMCDiagnostics: Markov Chain Monte Carlo convergence diagnostics
PNICER: Extinction estimater
REBOUNDx: Adding effects in REBOUND N-body integrations
reproject: Python-based astronomical image reprojection
RRATtrap: Rotating Radio Transient identifier

Scintools: Pulsar scintillation data tools
SEDkit: Spectral energy distribution construction and analysis tools
TLC: Tidally Locked Coordinates
tlpipe: Data processing pipeline for the Tianlai experiment
wobble: Time-series spectra analyzer