Finding Targets for Habitable Worlds Observer: Extremely Precise Radial Velocity Surveys and the Hunt for Earth Analogs

Value of the Information & Strength of the Argument

The talk provides valuable insights into the current state of EPRV surveys and the challenges posed by stellar activity. Ford effectively argues that the transition from photon-limited to activity-limited observations requires a paradigm shift in data analysis, moving towards data-driven models that must be carefully validated. He supports his arguments with concrete examples, such as the EXPRES solar signals project where different groups disagreed on the sign of a signal, illustrating the need for robust validation methods. The discussion of Sun-as-a-star observations is particularly compelling, as it offers a unique opportunity to test models against known truth. The argumentation is logical and well-structured, though it is more of a synthesis of ongoing work rather than a presentation of a single breakthrough.

Scientific Rigor, Source Quality, Title Accuracy

Ford demonstrates scientific rigor by referencing multiple collaborative efforts and recent publications, including the NASA-NSF EPRV Working Group report and studies by Bryson and Fernandez. He also mentions specific instruments and projects, such as NEID, EXPRES, and HARPS-N, which adds credibility. The title accurately reflects the content, and the talk stays on topic throughout. The presentation is well-organized and the technical level is appropriate for a specialized audience. The sources cited are relevant and appear to be reliable, though the talk does not provide a formal reference list, relying instead on verbal mentions.

The title accurately reflects the content, which focuses on the search for Earth analogs via radial velocity surveys and their relevance to the Habitable Worlds Observatory.

8/10

The talk is given by a distinguished professor with extensive experience in exoplanet research, and it synthesizes results from multiple collaborative efforts, including NASA-NSF working groups and recent publications. The content is technically rigorous and well-referenced, though it is primarily a review and forward-looking perspective rather than a presentation of new original data.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 02:00Introduction: Why radial velocity is important for exoplanet community and the goal of characterizing 25 potentially habitable planets.
• 08:00Discussion of occurrence rates of Earth-sized planets from Kepler data and the uncertainty in eta_Earth.
• 15:00Presentation of the NASA-NSF EPRV Working Group roadmap and various telescope architectures considered.
• 25:00Transition to stellar activity as the dominant noise source and the need for data-driven models.
• 35:00Introduction of Sun-as-a-star observations and the NEID Solar Telescope at WIYN Observatory.
• 45:00Comparison of multiple solar telescopes and the short-term variability at the meter-per-second level.
• 55:00Discussion of the need for validation of data-driven models and the challenges of trusting them for mission decisions.
• 1:05:00Conclusion: Urgency of making progress to inform HWO mission design and the potential of a targeted survey.

• NASA-NSF EPRV Working Group Report — Cited as the 2019 roadmap for EPRV surveys.
• Bryson et al. (2021) — Mentioned as a recent review on occurrence rates of potentially habitable planets.
• Fernandez et al. (2021) — Mentioned as a recent review on occurrence rates and biases.
• Criss et al. (2021) — Referenced for baseline mission yield estimates for HWO.

• NASA Exoplanet Archive — Provides data on exoplanet occurrence rates and properties.
• NEID Solar Telescope — Instrument discussed in the talk for solar observations.