• 00:00    |    
    Initial credits
  • 00:12    |    
    Exoplanet Detection Techniques: Part II
  • 00:30    |    
    Direct imaging technique
    • Requirements for direct imaging
    • Diffraction
    • Spatial resolution
    • Ground-based limitations
    • Direct imaged planet candidates
    • Direct imaged planet properties - Extrasolar Planets Encyclopedia
    • Inferring mass and size from a model
    • Pluto's mass and the problem of flux measurement
    • Planet-star flux ratios
  • 23:00    |    
    Microlensing technique
    • Microlensing animation
    • The concept of gravitational lensing
    • Microlensing basics
    • Planet-finding concepts
    • Microlensing planet light curves
    • Microlensing technique summary and relevance
  • 45:59    |    
    Astrometry technique
    • Astrometry definition and basics
    • Astrometry planet light curves
    • Astrometry technique summary
  • 56:08    |    
    Lecture II Summary
  • 58:53    |    
    Questions and comments section
    • Is microlensing the only technique that will help us find earth-mass planets?
    • What objects are causing microlensing?
    • Can the variability of a star be confused with microlensing?
    • Which part of the diagram does astrometry cover?
    • Which techniques are going to extend coverage of the diagram?
    • Will microlensing extend the bottom portion of the diagram?
    • Debris disks as a future technique to develop
  • 01:08:10    |    
    Final words
  • 01:08:18    |    
    Final credits

Exoplanet Detection: Techniques II

New Media  | 10 de diciembre de 2013  | Vistas: 3

In this video, Sara Seager continues her lecture on exoplanet detection techniques. Seager provides a description of the direct imaging technique, its specific requirements and ground-based limitations, and the importance of the concepts of diffraction and spatial resolution. In direct imaging, given a measurement of brightness, planet mass and size must be inferred from a model, often leading to inaccurate size representations - such is the case of Pluto. The technique remains useful nonetheless. Seager then overviews microlensing, an approach of important aesthetic value that requires tracking one-time lecture events and completing intricate mathematical calculations. Despite its complications, it remains the ideal means to find earth-mass planets. Microlensing may eventually cover an important section of the exoplanet occurrence diagram that is alien to other methods. Finally, astrometry is a technique that will be useful in completing the exoplanet discovery spectrum in the future, despite not having any formal planet detections yet. The final goal, Seager concludes, is to complete the occurrence plot as much as possible, and in the process, to discover distinct features that will allow scientists to better understand planet formation.

See: Exoplanet Detection: Techniques I, for the first half of this lecture.


Sara Seager is an astrophysicist and planetary scientist at the Massachusetts…


Nuestra misión es la enseñanza y difusión de los principios éticos, jurídicos y económicos de una sociedad de personas libres y responsables.

Universidad Francisco Marroquín