About this Article

Introduction

Our knowledge of galaxy formation and evolution has greatly expanded in recent decades thanks to large survey programs, including those carried out with the Hubble Space Telescope (HST). These programs led to numerous discoveries, deepening our understanding of the properties of high-redshift galaxies, the evolution of galaxy morphology over cosmic time, the physics of quenching and feedback mechanisms, populations of faint or optically obscured AGN, and enabling a new era of multi-wavelength photometric redshifts. But to significantly further advance in the future, we need to expand our observations to exploit wide-field capabilities beyond Hubble's relatively narrow sky coverage. In the next decade, this can be accomplished via surveys with upcoming facilities such as the James Webb Space Telescope, the Vera C. Rubin Observatory, the Euclid Mission, and the Nancy Grace Roman Space Telescope, formerly named the Wide Field Infrared Survey Telescope (WFIRST).

Specifically, the Roman Space Telescope, planned for launch in the mid-2020s, will provide Hubble-quality imaging over 0.28 sq. degrees (a field of view about a 100x larger than HST/ACS) at wavelengths between 0.5 microns and 2 microns. In addition to performing community surveys, the Roman Space Telescope will support a Guest Observer program and archival investigations of all Roman data, which will be open to the community with no proprietary period. Roman's large field of view will enable vastly larger galaxy surveys than possible with HST. The 2020 Roman Conference on Galaxy Formation and Evolution in the Era of the Nancy Grace Roman Space Telescope was held on 5–9 October, 2020, with the goal of engaging the extragalactic community in exploring how we can synergistically advance our knowledge of this exciting field.

Science Highlights

The conference featured 14 invited speakers, 36 contributed talks and 67 posters, addressing the topics of high-redshift galaxies, AGN, data science, star formation and dust, synergies with other missions, theory and simulations, galaxy properties, and connections to the dark matter field. The invited talks addressed the Roman mission, a review of the field, ways to advance inclusion through access, topical presentations from members of the community, and work done by the Science-Investigation Teams (competitively selected teams who assist on science requirements, mission design, and scientific performance for the mission).

A recurring theme throughout the week was that the impressive field of view and spatial resolution of the wide-field instrument will make the Roman Space Telescope ideal for finding and characterizing rare objects, though it manifested itself differently during each session. At the highest redshifts, Rebecca Bowler showed how a number of the most luminous galaxies constrain the properties of quenching and dust. Similarly, the large-area surveys with Roman are excellent pathfinders for the highest-mass supermassive black holes, which are excellent targets for subsequent detailed dynamical studies (see the presentation by Jonelle Walsh). Strong gravitational lenses represent important links between dark and luminous matter, and due to their scarcity, Tommaso Treu compared them to "Shamrocks: finding one is hard, but when you find it, it gives you unique information." This rare-source theme was present even in the Milky Way, where members of diffuse stellar streams (Sarah Pearson) and the Galactic halo (James Bullock) will be readily identified in the rich datasets of Roman.

This ability to find rare objects is not a birthright of Roman, but will require diligent care and preparation by the community. First, observations at additional wavelengths must be synergistically obtained with other facilities; the importance of optical data from the Vera Rubin Observatory and other ground-based facilities was reinforced throughout the week. Additionally, Euclid will pave the way for large-area surveys from space by surveying 15,000 square degrees to AB ~ 24 mag and somewhat bluer than Roman. Secondly, the massive volume of the joint datasets from Roman and additional observatories will demand we rethink analysis methods, strategies, and techniques. The use of machine and deep learning has emerged in the world of data science as the foremost tool for sifting through big data: Brant Robertson highlighted how the combination of computing strategies and algorithms can yield new image classification tools. Eric Gawiser showed that this sea change invites us to ask new questions or reframe old ones, such as the parametric formulation of complex star-formation histories and spectral energy distribution (SED) models.  

On the first Conference day, Monday, Dara Norman spoke about how the access to big data, like that generated by Roman, can advance inclusion but will demand investments in resources, such as deliberate efforts to ensure the various resource allocation committees and advisory roles are composed of a spectrum of scientists spanning various axes of diversity. Additionally, the community must commit to curating and refining policies such as the dual-anonymous selection protocols, with the intent of establishing an ethos that research inclusion is valued as part of the scientific merit and process.

All of the materials generated by and for the conference (such as schedule, slides, videos, posters, transcripts, and summaries) will be posted as e-proceedings on Zenodo. This not only provides a DOI for the authors, but also preserves the content for posterity. Figure‑1 shows the compact schedule, but full details (including talk titles) can be found at the conference homepage. All presentations were recorded and the videos are available on the STScI panopto server. 

Virtual Attendance

Due to the COVID-19 pandemic, the conference was conducted entirely online for five hours each day—four hours for talks and one hour for posters. Approximately 300 people registered for the conference, with an average daily attendance of 250 from 22 countries. Almost 130 abstracts were submitted, of which 36 were selected for contributed talks using a double-blind process. See the accompanying article in this newsletter on Conference Diversity Statistics [URL]; Figure 2 shows the daily attendance. Registered users were invited to watch presentations through the BlueJeans Events App and ask questions of the speakers in a companion Slack workspace (see Fig. 3), where each session was assigned a separate channel and its constituent talks a separate thread. Live captioning was provided by CaptionMax for every talk, and transcripts will be published as a part of the e-proceedings. Additionally, each iPoster had its own channel, which allowed for static and/or complex multimedia content to be viewed. This combination of software allows for synchronous and asynchronous participation, which was vitally critical as participants were scattered throughout numerous time zones. For the Science Organizing Committee, there was a Slack channel to communicate with participants, which relieved the traffic on the BlueJeans channel and allowed everyone to concentrate on the talks in that window. We also created a backdoor SOC channel for coordination, troubleshooting, and general mutual support.

The entire conference was simultaneously live-streamed on Facebook (as seen in Fig. 4), where it reached an additional ~200 people and garnered ~100 page likes throughout the week. The talk videos are also archived on Facebook, and each has already been viewed hundreds of times.  

Concurrent Events

STScI Public Lecture: STScI conducts a monthly public lecture, and during the week of the conference it featured two prominent figures in the space-based astronomy community: Jennifer Wiseman (Senior Project Scientist for the Hubble Space Telescope) and Julie McEnery (Project Scientist for the Roman Space Telescope), who spoke about the visionary scientist, Nancy Grace Roman, and the legacy that the telescope named in her honor is sure to leave. Nancy Grace Roman was NASA's first chief astronomer in 1960, the first woman to ever hold an executive position at NASA, and is widely considered to be the "Mother of the Hubble Space Telescope" for her pivotal role in creating the field of space-based astronomy. Now we honor her with a space telescope that will provide imaging quality similar to that of the Hubble Space Telescope, but will be ~400 times more efficient due to the field of view and orbit. The archived lecture is available on YouTube.

The Science Writers' Workshop: On the opening day of the conference, STScI's Office of Public Outreach held a workshop for approximately 30 science writers to brief them on the Roman Space Telescope and some key science areas that this mission will address. The invited speakers and their topics were:

• Olivia Lupie (NASA/GSFC) – About Nancy Grace Roman
• Julie McEnery (NASA/GSFC) – Roman Space Telescope and Wide Field Instrument
• Jason Rhodes (NASA/JPL) – Coronagraph Instrument
• Adam Riess (STScI/JHU) – Dark Energy
• Rachel Somerville (Flatiron Institute/Rutgers University) – Galaxy Evolution
• Harry Ferguson (STScI) – Synergies with Other Observatories

The resulting video was archived on YouTube.

Summary

With the Nancy Grace Roman Space Telescope, we honor the pioneering scientist whose vision laid the foundation for the space-based observatories that have revolutionized every aspect of modern astrophysics. The Roman Space Telescope will launch in the mid 2020s, and due to its unmatched field of view and excellent angular resolution, will proverbially rewrite the galaxy-evolution text books. Throughout the week we saw how the Roman Space Telescope reinvigorates topics from ultrafaint nearby galaxies and stellar streams in the Milky Way halo to cosmic reionization and high-redshift AGN, and everything in between. Furthermore, the unfettered access to the entire canon of data is a major step forward in advancing inclusion, but we must be mindful of the many more steps to be taken. 

The participation of approximately 300 astronomers, and the almost 120#nbsp##talks and posters presented by the extragalactic research community during this virtual conference underscores the vitality of the field. Among the contributed talks and posters, the representation of graduate students (33%) and early-career scientists (38%) is high. The double-blind selection of abstracts for contributed talks (described in the Conference Diversity Article in this Newsletter [LINK]) led to 44% of these talks being given by women.

Additional Reference Materials

Can Big Data Lead an Inclusion Revolution? by Dara Norman

The Roman Space Telescope at STScI

The Roman Space Telescope at NASA/Goddard

The Roman Space Telescope at IPAC

Review article on Astrobites blog

The conference webpage at STScI