Exoplanets

• Shirtsleeve twin - my idea, where we could survive without spacesuits
  • 1 Earth size
  • 2 "Habitable" zone
  • 3 low eccentricity
  • 4 a large moon
  • 5 a large Jupiter to deflect impactors
  • 6 approximately 50% ocean
  • 7 plate tectonics
  • 8 plants are implied for oxygen atmosphere

Exoplanets, 2010, Sara Seager

• p4 http://exoplanet.eu Fig. 1: graph of known exoplanets in July 2010

  • this graph does not include eccentricity
• Radial Velocity - Lovis and Fischer
  • p38 1993 ELODIE 7m/s (Observatorie de Haute-Provence France), 2003 CORALIE3-5 m/s at La Silla, 2006 SOPHIE 3m/s (OHP France)
  • p38 2003 High Accuracy Radial velocity Planet Searcher, HARPS, 0.5 to 0.2 m/s, European Southern Observatory 3.6 meter telescope at La Silla Chile
• Astrometry (wobble of star) - Quirrenbach
  • No results as of 2010
• Timing - Wolszczan and Kuchner
  • pulsars or stable oscillation stars
• Gravitational Microlensing - Gaudi
• Transits - Winn
• Direct Imaging - Traub and Oppenheimer

Exoplanets, Michael Summers and James Trefil

Hillsboro, 523.24 Summers 2017

Index skimmed ... not interesting, not much new, some errors. No explicit references or citations.

For example, page 6 mentions "Styrofoam worlds -- planets so light that we cannot figure out why they don't collapse under their own gravity" That is the last indexed mention. News reports about Kepler 7b (an early discovery) are titled "Styrofoam world", about a Jupiter-sized (but 10% as dense) exoplanet, hence a density around 0.13 g/cm³. Foamed polystyrene is 0.05 g/cm³ (and solid polystyrene is about 1 g/cm³). "we cannot figure out" may mean the authors can't choose among many proffered explanations, including experimental error, or simply a Saturn mass gas giant so hot that its outer layers are very large. Without reading the entire book, the index and the table of contents provide no clues.

Better to spend my limited time looking at primary literature.