The Rocky Worlds DDT Core Implementation Team (CIT) at STScI is pleased to announce that, following discussions and a recommendation from the Science Advisory Council (SAC), the exoplanet TOI-1452b has been added to the Rocky Worlds DDT sample, replacing TOI-406c. The CIT estimates that 12 secondary-eclipse observations of TOI-1452b with MIRI 15 μm photometry, together with HST ultraviolet observations of the host star, will be sufficient to achieve the program's science objectives for this target. This change was driven by detailed CIT analyses showing that TOI-406c, which lies deep into the "dry" side of the Cosmic Shoreline, would require about 14 secondary-eclipse observations to meaningfully constrain its atmosphere. This time investment was deemed too high by the SAC and CIT leads. In contrast, TOI-1452b lies just on the "wet" side of the Cosmic Shoreline, is a smaller investment of time, and complements the rest of the sample. For further details, see the corresponding JWST Observers News Article.

The Organizing Committee of the Rocky Worlds DDT Workshop is excited to announce that registration is now open. This workshop is a community gathering focused on the science enabled by the Rocky Worlds Director’s Discretionary Time (DDT) program, with particular emphasis on its JWST/MIRI observations. The workshop will serve as the culmination of the Rocky Worlds DDT Data Challenge, bringing participants together to compare analysis methods and discuss the results and their scientific implications. A key component will be the unveiling of the underlying data-generating process as well as a hackathon to enable a direct and meaningful comparison across approaches.

The Rocky Worlds Core Implementation Team (CIT) is excited to announce the Data Challenge is oficially open. For details on how to participate, visit the official Kaggle website of the Challenge. There was a virtual information and tutorial session on Tuesday, June 9th, 2026, at 11:00 a.m. U.S. Eastern Time (ET) that can be viewed in WebEx. This session introduces details about the Data Challenge as well.

The Rocky Worlds Core Implementation Team (CIT) will soon launch the Rocky Worlds DDT Data Challenge, aimed at engaging the community in the analysis and interpretation of JWST MIRI 15 μm time series observations of terrestrial exoplanets in eclipse. Researchers interested in participating or receiving updates on Rocky Worlds DDT–related news and announcements should sign up for the Rocky Worlds DDT News Mailing List Questions may be sent to RockyWorldsDDT

A new plot showing the JWST visibility windows for all the RW exoplanets has been added to the Status webpage. This plot will be updated regularly by the Core Implementation Team (CIT).

NASA has published a public-friendly overview of the Rocky Worlds program developed by STScI’s Office of Public Outreach. The article covers why we are interested in rocky planets orbiting M dwarfs; what scientific questions we are trying to answer; and how we are using Webb and Hubble to answer these questions. Eight graphics explaining the basic concepts are available for download, along with extended captions and alt text. All of the content is public domain, available for use in any presentation or publication.

The very first High Level Science Products (HLSPs) for the Rocky Worlds DDT have been published in MAST. These include the first JWST/MIRI 15 um light curve observations of GJ 3929 b, as well as the first HST/STIS stellar Lyman-alpha observations.

The Rocky Worlds DDT's Core Implementation Team (CIT) at STScI, along with the external Science Advisory Council (SAC), have made a few updates to the list of target candidates. Five new exoplanets will be added to the Rocky Worlds DDT sample :

• TOI-198 b
• TOI-406 c
• TOI-771 b
• HD 260655 c
• TOI-244 b

bringing the total of RW exoplanets to nine to be studied in detail in the next three years. Details will be posted in the scheduling webpage. Read the complete updates in the following document

• Download   PDF document with updates

The Rocky Worlds DDT's Core Implementation Team (CIT) at STScI, along with the external Science Advisory Council (SAC), have made a few updates to the list of target candidates. Two new exoplanets will be observed :

• LTT 1445 A b
• LHS 1140 b

Also, the first secondary eclipse time series observations of GJ 3929 b have been scheduled with JWST/MIRI, and the first observations of the host star GJ 3929 in the UV have been scheduled with HST/STIS. You may see the details in the scheduling webpage In addition, we have revised the observing strategy based on recommendations by the SAC. Read the full updates in the following document

• Download   PDF document with updates

The Rocky Worlds DDT scheduling webpage is now active with target GJ-3929 b program and eclipses information.
New targets will be included as their APT files become available and their JWST and/or HST observations are planned.

The Rocky Worlds DDT website became live on April 10th 2025.

The recording of the Rocky Worlds DDT's second information session, held on January 21st, 2025, has been uploaded as well as the meeting slides. The deadline to submit feedback was April 4th, 2025.

• Watch the meeting video
• Download   the meeting slides
• Submit feedback to the TUC    Deadline was April 4th, 2025

The Rocky Worlds DDT Program will use JWST to search for atmospheres around a dozen nearby M-dwarf exoplanets while using HST to characterize activity in the host stars. Over the past month, community members have provided feedback on a provisional set of targets — the Targets Under Consideration (TUC) list. Based on that feedback, the Science Advisory Council (SAC), together with the Leads of the Core Implementation Team (CIT), have identified an initial set of targets for JWST MIRI 15 µm photometry:

• LTT 1445 A c (11 eclipses)
• GJ 3929 b (15 eclipses)

Further targets will be selected after the results of the JWST Cycle 4 Call for Proposals are published in March 2025. Proposers may not apply for Cycle 4 Archival Research programs to analyze these data, as STScI cannot guarantee that all data will be in the archive when Cycle 4 begins. However, the SAC and CIT leads would like to encourage the community to consider JWST Cycle 4 proposals for complementary and supplementary observations of these targets or Theory programs. The standard JWST Duplication Policies apply. Additional exoplanet targets will be selected after the results from the Cycle 4 Telescope Allocation Committee are known. The DD program will be structured to avoid duplicating Cycle 4 General Observers programs.

A new 500-hour Director's Discretionary Time (DDT) program will use JWST observations to search for atmospheres in more than a dozen nearby exoplanet systems. In tandem, around 250 orbits of ultraviolet observations with the Hubble Space Telescope will be devoted to characterize the activity of the host stars. While the implementation of this program will be led by an STScI Core Implementation Team, a Science Advisory Committee (SAC) has also been defined. The membership of this body is drawn from the broader exoplanet community. They will provide advice on all aspects of the program, including target selection, data verification, and equitable community interactions. An open call to join this Council was circulated in early August 2024 and received over 70 nominations from all around the world. A group of 3 previously appointed Council members performed the selection of 9 new Council members out of all the applications, using a varied range of selection criteria including the nominee's scientific and technical expertise, demonstrated collaborative and organizational experience, and commitment to represent the broader community. The full list of Science Advisory Council members is:

• Rory Barnes (University of Washington, USA)
• Natasha Batalha (NASA/Ames, USA)
• Bjorn Benneke (Université de Montréal, Canada)
• Adina Feinstein (Michigan State University, USA)
• Kevin France (University of Colorado, USA)
• Aishwarya Iyer (NASA/GSFC, USA)
• Daniel Koll (Peking University, China)
• Laura Kreidberg (MPIA, Germany)
• Rafael Luque (University of Chicago, USA)
• Megan Weiner-Mansfield (ASU/Maryland, USA)
• Kevin Stevenson (JHU/APL, USA)
• Allison Youngblood (NASA/GSFC, USA)

The first Information Session and Q&A on the Rocky Worlds project took place on August 16th, 2024 and the meeting video is available in the link below.

• Watch the meeting video

The STScI Director, Dr. Jennifer Lotz, has accepted the primary recommendation of the Working Group on Strategic Exoplanet Initiatives, and has decided to proceed with a large-scale survey of rocky M-dwarf exoplanets. The program will use around 500 hours of Director’s Discretionary Time on the James Webb Space Telescope to search for atmospheres in more than a dozen nearby systems. Approximately 250 orbits of ultraviolet observations with the Hubble Space Telescope will be used to characterize the activity of the host stars. The observations will be executed by an STScI Core Implementation Team led by Dr. Nestor Espinoza, supported by Dr. Hannah Diamond-Lowe as the team Deputy. STScI is also recruiting an external Science Advisory Committee (SAC) to provide advice on all aspects of the program, including target selection, data verification, and equitable community interactions. The SAC membership will be representative of the broader exoplanet community, spanning a wide range of institutional affiliations and career stages. STScI will shortly announce an opportunity to submit nominations, including self-nominations. Community input will be solicited on the target list; observing plans will be published well in advance of the JWST Cycle 4 deadline.