A Data Science Platform to Enable Time-domain Astronomy

Abstract

SkyPortal is an open-source software package designed to discover interesting transients efficiently, manage follow-up, perform characterization, and visualize the results. By enabling fast access to archival and catalog data, crossmatching heterogeneous data streams, and the triggering and monitoring of on-demand observations for further characterization, a SkyPortal-based platform has been operating at scale for >2 yr for the Zwicky Transient Facility Phase II community, with hundreds of users, containing tens of millions of time-domain sources, interacting with dozens of telescopes, and enabling community reporting. While SkyPortal emphasizes rich user experiences across common front-end workflows, recognizing that scientific inquiry is increasingly performed programmatically, SkyPortal also surfaces an extensive and well-documented application programming interface system. From back-end and front-end software to data science analysis tools and visualization frameworks, the SkyPortal design emphasizes the reuse and leveraging of best-in-class approaches, with a strong extensibility ethos. For instance, SkyPortal now leverages ChatGPT large language models to generate and surface source-level human-readable summaries automatically. With the imminent restart of the next generation of gravitational-wave detectors, SkyPortal now also includes dedicated multimessenger features addressing the requirements of rapid multimessenger follow-up: multitelescope management, team/group organizing interfaces, and crossmatching of multimessenger data streams with time-domain optical surveys, with interfaces sufficiently intuitive for newcomers to the field. This paper focuses on the detailed implementations, capabilities, and early science results that establish SkyPortal as a community software package ready to take on the data science challenges and opportunities presented by this next chapter in the multimessenger era.

Characterizing the Ordinary Broad-line Type Ic SN 2023pel from the Energetic GRB 230812B

“…We ingested the GBM localization map (Goldstein et al 2022) into Fritz (van der Walt et al 2019), the ZTF instance of SkyPortal (van der Walt et al 2019;Coughlin et al 2023), an interactive tool designed to plan and schedule target-ofopportunity observations for ZTF. The observing plan was generated using gwemopt (Coughlin et al 2019) by taking the healpix Fermi-GBM localization map, slicing the sky map into predefined tiles of the size and shape of the ZTF field of view, determining which fields have the highest enclosed probability, and optimizing observations based on air mass and visibility windows.…”

SAGUARO: Time-domain Infrastructure for the Fourth Gravitational-wave Observing Run and Beyond

“…The complexity of our observing program and the necessity of responding in real time to alerts and incoming data require that we centralize all of our tools for planning observations, monitoring data, vetting targets, and reporting results in a single location that is accessible to all team members at all times. Current transient surveys and large follow-up programs use similar systems, including the Asteroid Terrestrial-impact Last Alert System (ATLAS) Transient Science Server (Smith et al 2020), the Global Rapid Advanced Network Devoted to the Multi-messenger Addicts' Interface and Communication for Addicts of the Rapid follow-up in multi-messenger Era (Antier et al 2020a), the Global Relay of Observatories Watching Transients Happen Marshal (Kasliwal et al 2019), the Global Supernova Project's Supernova Exchange (Howell & Global Supernova Project 2017), the Public ESO Spectroscopic Survey of Transient Objects Marshall (Smartt et al 2015), the Young Supernova Experiment's YSE-PZ (Coulter et al 2023), and the Zwicky Transient Facility's Fritz (based on SkyPortal; Coughlin et al 2023).…”

An Optically Discovered Outburst from XTE J1859+226

“…We also triggered Swift target-of-opportunity observations and confirmed that the X-ray flux had increased by three orders of magnitude relative to the quiescent level (Bellm 2021b). We used a customized Skyportal (van der Walt et al 2019;Coughlin et al 2023) instance ("Fritz") for managing follow-up data.…”