About this Article

The Nancy Grace Roman Space Telescope’s Wide Field Instrument will provide Hubble-like resolution and sensitivity combined with a field of view ~200 times that of Hubble in the near infrared, with both imaging and slitless spectroscopy capabilities. Combined with impressive slew and settle times, the Roman Space Telescope will yield survey speeds more than 1,000 times faster than that achievable with Hubble. Roman’s resulting survey datasets will be transformational for a broad range of astrophysics. Roman is being prepared for launch as soon as October 2026, and no later than May 2027.

Roman is in large part a community-defined mission. The majority of Roman’s observing time for the first five years of the mission will be devoted to surveys that are being defined by the science community. This includes Roman’s Core Community Surveys, which will serve to meet Roman’s mission-level science requirements for investigating the nature of dark energy and the fate of the universe, and the demographics of exoplanets. It also includes a recently accepted recommendation for an early definition of a Galactic Plane General Astrophysics Survey. The primary goal for the definition of each of these surveys is to maximize the science performed with Roman’s infrared surveys.

There will also be opportunities to propose for Principal Investigator-led General Astrophysics Surveys, with the first opportunity opening approximately one year before launch. A minimum of 25% of Roman’s observing time will be reserved in the first five years for General Astrophysics Surveys, which will primarily be selected via traditional peer-reviewed calls for proposals. All Roman data will be public immediately, and Roman calls for proposals will also provide the opportunity to apply for funding to analyze and perform scientific investigations on all existing or to-be-acquired Roman data, including the Core Community Surveys and approved General Astrophysics Surveys.

Progress Towards Defining Roman’s Core Community Surveys

The process of the community definition of Roman’s three Core Community Surveys kicked off in early 2023 with a series of open calls to the science community. In the winter of 2023, the Roman mission released a call for input in the form of short science pitches describing investigations the science community wanted enabled by the surveys. This was followed by a request in the spring of 2023 for white papers, describing in more detail science investigations that could be enabled by the surveys, the observational strategies that would enable the investigations, and metrics or figures of merit that could be used to assess the impact of trades in observational strategy on the described science investigation. Finally, in the summer of 2023, a call was released for self-nominations for serving on the committees being formed to define the Core Community Surveys.  

A strong response was received from all three calls, covering a broad range of scientific expertise. The science pitch responses were summarized in a previous STScI newsletter article. View the individual science pitch submissions. The 74 white paper responses were similarly broad, covering topics ranging from solar system science to cosmology and the large scale structure of the universe.  

Guided by the content of the science pitch and white paper submissions, a survey definition committee has been formed for each of the three Roman Core Community Surveys. The committee membership was selected to ensure that the breadth of interests of the scientific community in using Roman’s Core Community Surveys was well represented. The committees’ charter charges them with assessing community input, investigating various observational strategies to maximize the science return of the survey, and producing a recommendation for multiple survey options (such as a minimal, nominal, and optimal survey definition). The committees are expected to deliver a report summarizing the recommended survey options, including a discussion of the scientific tradeoffs, the time required, and the observational constraints of each option to the Roman Project by November 1, 2024 for dissemination to the Roman Observations Time Allocation Committee (ROTAC). The ROTAC will review the input of the committees and make a recommendation to the Roman Project at NASA Goddard by January 2025 on the implementation of the surveys and the amount of time to be dedicated to each survey. See the full charter of the Core Community Survey Definition Committees.

The committees are currently finalizing their review of community input and prioritizing the most compelling scientific investigations for driving the survey design. They will shortly move into discussing potential survey strategies and assessing their impact on the overall science return of the survey. Members of the science community with additional ideas for science investigations they would like to see enabled by Roman’s Core Community Surveys are encouraged to use the science pitch submission form to communicate those ideas to the committees. However, time is of the essence: given the current status of the survey definition work, additional ideas should be submitted as soon as possible. Ideas submitted while the committees are still finalizing review of community input and prioritizing science investigations will have the most impact on the definition process.  

Definition of Roman’s Galactic Plane Survey

The Roman Project previously released a Request for Information to the science community in order to solicit comments on (a) whether to select an Early-Definition General Astrophysics Survey, and (b) to outline and submit survey concepts that would demonstrably benefit from selection as an Early-Definition General Astrophysics Survey. Twenty complete submissions were received with over 340 unique authors. Review of these submissions has been completed by an Early-Definition Astrophysics Survey Assessment Committee. The committee found that there was sufficient justification to define an Early-Definition General Astrophysics Survey through a community-led process. The top ranked concept was a survey of the Galactic plane. View the committee's final report.

Accordingly, a community-defined Roman Galactic Plane General Astrophysics Survey, of up to approximately 700 hours, will be defined prior to the first Roman call for proposals by a committee of community members utilizing community input in an analogous method to the definition of Roman's Core Community Surveys by the Core Community Survey definition committees. There are no mission-level science requirements on a Roman Galactic Plane Survey, leaving the full parameter space available to define the observational strategies (filters, depth, cadence, etc.) in a way that will enable a broad range of astrophysical investigations with Roman data of the Galactic Plane.

The definition of Roman’s Galactic Plane Survey will follow a similar community-oriented approach as that used for defining the Core Community Surveys, albeit with a shorter timeline for compiling community input. A single request has been made for input in the form of either short science pitches or longer, more technical white papers, as well as for self-nominations to be on the definition committee for the Galactic Plane Survey. Responses are requested by May 20, 2024.

How to Contribute

For those wishing to contribute to the scientific conversation about Roman’s community-defined surveys, there are additional avenues beyond responding to formal requests for input.  

Notably, members of the science community who wish to be involved in collaborative work and discussion resulting in direct input to the Roman project and survey definition committees should explore joining a working group. These working groups are meant to give the community a voice in aspects of Roman’s operations that will impact the ability of the science community to undertake various science investigations (e.g., calibration, software, simulations, survey definition). Two working groups are currently active (calibration, software), one is in the start-up process (simulations), and others are in the process of being formed. Members of the science community can indicate their interest in joining current or forming working groups.  

A Roman science collaboration, anticipated to be formed later in 2024, will provide opportunities to join in conversations with a community of scientists interested in Roman, and to work collaboratively on Roman science topics with other scientists interested in exploring the scientific capabilities of, and preparing to analyze, Roman datasets.  

A series of Roman science conferences, held approximately each year, also provides an opportunity to learn about, and communicate work on, Roman’s scientific capabilities. The next conference, “Challenging Theory with Roman: From Planet Formation to Cosmology,” is being held July 9-12, 2024 in Pasadena, CA, with a registration deadline of June 24. In addition to the scientific program, this conference will provide an opportunity to interact with members of the Core Community Survey definition committees. 

How to Stay Informed

Roman is being developed and operated under a distributed model, with multiple project partners. These include the Project Science Office at NASA Goddard, the Science Operations Center at STScI, and the Science Support Center at IPAC, as well as industry and academic partners. To receive periodic updates, announcements of Roman events, and future requests for community input, sign up to one or more of the Roman mailing lists maintained by NASA Goddard, STScI, and IPAC. Major community announcements are made and general Roman news is included across all three lists, while more focused updates specific to each institution are generally sent to that institution’s mailing list.  

STScI publishes a Roman newsletter that highlights major Roman milestones and updates on STScI’s Science Operations Center for Roman; it can be subscribed to by checking "Roman Updates" in your myST account preferences (the preferred method), or by sending a blank email to roman_soc_news-subscribe-request@maillist.stsci.edu. The Roman Science Support Center at IPAC similarly publishes regular updates on their work and activities, including a monthly virtual lecture series. See information on subscribing to the Science Support Center Roman mailing list. The Roman Project Science Office at Goddard Space Flight Center announces major project updates, as well as a regular virtual Roman Community Forum meeting providing updates on Roman mission status and plans, through its Roman mailing list; it can be subscribed to by sending an e-mail to roman-news-join@lists.nasa.gov. Including a subject in the email helps prevent an issue where a subscription submission could be quietly deleted. More informal and frequent updates on Roman activities can be obtained by following the Roman Forum Confluence site.