FROM DEAD to HABITABLE EXOPLANETS at ARECIBO the Science and Outreach of the PHL @ UPR Arecibo

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FROM DEAD TO HABITABLE EXOPLANETS AT ARECIBO The Science and Outreach of the PHL @ UPR Arecibo Abel Méndez Planetary Habitability Laboratory University of Puerto Rico at Arecibo Four Types of Exoplanets Dead Habitable Living Intelligent Planets Planets Planets Planets ARECIBO OBSERVATORY ARECIBO OBSERVATORY University of Puerto Rico at Arecibo A virtual laboratory of the habitable universe Credit: PHL @ UPR Arecibo What is an Habitable Exoplanet? Credit: NASA/Wikimedia Commons/Nickelodeon What is a PotenRally Habitable Exoplanet? Right Orbit (within the HZ) Right Size (0.5 — 2.0 RE) F Superterran 1.18 — 2.84 AU SuperEarth-size 1.25 — 2.0 R E G 0.75 — 1.84 AU Terran Earth-size 0.8 — 1.25 RE K 0.48 — 1.23 AU Subterran Mars-size M 0.5 — 0.8 RE 0.09 — 0.24 AU Credit: PHL @ UPR Arecibo StasRcal DistribuRon of Habitable Exoplanets ηEarth αEarth δEarth Frequency Diversity Distance Credit: PHL @ UPR Arecibo Habitability Metrics for Exoplanets ESI HZD SPH 0 0.5 1.0 -1 0 +1 0 0.5 1.0 Habitable Zone Earth Similarity Index Habitable Zone Distance Standard Primary Habitability (stellar flux, mass/radius of planet) (HZ size, orbit of planet) (many parameters) Credit: PHL @ UPR Arecibo Prototype Habitable Exoplanets Earth- Earth= Earth+ [Barely habitable] [As habitable as Earth] [More habitable than Earth] Credit: PHL @ UPR Arecibo Planetary Classificaon Planetary bodies are classified based on their star, orbit, and size Example Earth G Warm Terran Star Type Size Type Orbit Type Jovian • Neptunian O • B • A• F • G • K • M Hot • Warm ‘HZ’ • Cold Superterran • Terran • Subterran L • T • WD • PSR Mercurian • Asteroidan CREDIT: PHL @ UPR Arecibo, NASA Hubble Over 1,000 Confirmed Exoplanets Terrestrial Gas Giants Mercurian Subterran Terran Superterran Neptunian Mercury-Size Mars-Size Earth-Size SuperEarth-Size Neptune-Size Jovian PotenGally habitable depending on orbit and size. Jupiter-Size Number of discovered confirmed exoplanets in red. Those sGll unconfirmed from the NASA Kepler Mission in green. Credit: PHL @ UPR Arecibo An Earth-like Exoplanet for Astronomers PHL @ UPR Arecibo phl.upr.edu A virtual laboratory studying the habitability of Earth, the Solar System, and Exoplanets Exoplanet Science • Habitability Metrics. • DefiniRon and Classificaon of Habitable Exoplanets. • Search for Habitable Exoplanets. Outreach • Educaonal Content and Workshops • Visualizaons .

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A Comparative Analysis of the Cobb-Douglas Habitability Score (CDHS) with the Earth Similarity Index (ESI)
A Comparative Analysis of the Cobb-Douglas Habitability Score (CDHS) with the Earth Similarity Index (ESI) Surbhi Agrawal1, Suryoday Basak1, Snehanshu Saha1, Kakoli Bora2 and Jayant Murthy3 I. Introduction and Methods is 1.27 EU, the radius is R = M 0.5 ≡ 1.12 EU1. Accordingly, the escape velocity was calculated by V = p2GM/R ≡ 1.065 (EU), and the density by A sequence of recent explorations by Saha et al. [4] e the usual D = 3M/4πR3 ≡ 0.904 (EU) formula. expanding previous work by Bora et al. [1] on using The manuscript, [4] consists of three related Machine Learning algorithm to construct and test analyses: (i) computation and comparison of ESI planetary habitability functions with exoplanet data and CDHS habitability scores for Proxima-b and raises important questions. The 2018 paper analyzed the Trappist-1 system, (ii) some considerations the elasticity of their Cobb-Douglas Habitability on the computational methods for computing the Score (CDHS) and compared its performance with CDHS score, and (iii) a machine learning exercise other machine learning algorithms. They demon- to estimate temperature-based habitability classes. strated the robustness of their methods to identify The analysis is carefully conducted in each case, potentially habitable planets from exoplanet dataset. and the depth of the contribution to the literature Given our little knowledge on exoplanets and habit- helped unfold the diﬀerences and approaches to ability, these results and methods provide one impor- CDHS and ESI. tant step toward automatically identifying objects of interest from large datasets by future ground and Several important characteristics were introduced space observatories.
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