A Path to an All-Sky Survey with Roman

TL;DR

This paper proposes a detailed plan for a space-based, near-infrared all-sky survey using the Nancy Grace Roman Space Telescope, aiming to provide foundational astronomical data and enable diverse scientific investigations.

Contribution

It presents a feasible, step-by-step approach to conduct the first-epoch high-resolution all-sky survey with Roman, including scheduling, early science goals, and community engagement strategies.

Findings

Cycle 1 will reach H~25.5 AB mag with 0.1'' resolution.

Survey will enhance synergies with LSST and Gaia.

Early data products will include catalogs of rare astronomical objects.

Abstract

A deep, space-based, all-sky near-infrared survey carried out with the Nancy Grace Roman Space Telescope would constitute a foundational astronomical infrastructure for decades to come. In this white paper, we present a concrete and feasible path to imaging the entire sky at $\sim0.1''$ resolution, beginning with high-impact fields in Cycle 1 and scaling to ultra-wide coverage within the nominal mission. This first-epoch survey will reach $\mathrm{H}\sim25.5$ AB mag (5$\sigma$) and maximize synergies with contemporaneous observatories, while preserving substantial time for other ambitious Roman programs. We outline representative scheduling scenarios and an example Cycle 1 program that triples early Roman-LSST overlap and delivers high-value community data products such as LSST forced photometry, joint \textit{Gaia}-Roman astrometry, and catalogs of Galactic substructure, stong lenses, and other rare systems. The Cycle 1 program will lay the foundation for an eventual all-sky survey, while also delivering high-impact early science. We invite broad community participation in shaping and carrying out both the initial program and the long-term vision of an all-sky Roman survey.