Planetary Spectroscopy and Imaging

Wesley A. Traub (Smithsonian Astrophysical Observatory)

Abstract:

In a few years we will be able to expand the search for planets around nearby stars to include not only the currently-detectable gas giants but also the potentially-detectable class of terrestrial planets. Our primary means of characterizing these planets will be optical and infrared spectroscopy. We can potentially learn about the surface temperature and pressure, atmospheric constituent gases, the presence of water or dust clouds, the surface composition, the presence of biomarkers, and the possibility of the existence of life on the planet. Once all of this is known, there will be a natural desire to obtain images of the planets, to inform us about the appearance of land masses, oceans, clouds, winds, seasons, and ice caps. In this talk I will discuss the means of making and interpreting these types of observations.

Realaudio of lecture.
Viewgraphs (4.4MB PDF)

Reading List:

• The Terrestrial Planet Finder (TPF): A NASA Origins Program to Search for Habitable Planets,
  Beichman, C.A.; Woolf, N.J.; Lindensmith, C.A., editors, JPL Publication 99-3, 1999, (this is the basic reference for the TPF mission; also available at http://tpf.jpl.nasa.gov).

• Exo-Earth Imager for Exoplanet Snapshots with Resolved Detail,
  Labeyrie, A., ASP Conference Series, 194, pp. 350-358, 1999, (shows how breaking the "golden rule" of separated telescopes can yield improved angular resolution at the expense of field of view; see also many other papers of interest in this volume).

• Theoretical Transmission Spectra during Extrasolar Giant Planet Transits,
  Seager, S.; Sasselov, D.D., ApJ, 537, pp. 916-92, 2000, (an example of planetary spectrum calculation).

• Albedo and Reflection Spectra of Extrasolar Giant Planets
  Sudarsky, David; Burrows, Adam; Pinto, Philip, ApJ, 538, pp. 885-903, 2000, (another example of planetary spectrum calculation).

• The Search for Extra-Solar Terrestrial Planets: Techniques and Technology,
  Shull, J. Michael; Thronson, Harley A.; Stern, S. Alan, editors, Kluwer Academic Publishers, 156 pp., 1997, (also available in Astrophysics and Space Science, 241, 1996).

• Combining Beams from Separated Telescopes,
  Traub, W.A., Applied Optics, 25, pp. 528-532, 1986, (delineates the "golden rule" of separated telescopes).

• Photochemistry of Planetary Atmospheres,
  Yung, Y.L.; DeMore, Wiliam B., Oxford University Press, 456 pp., 1999, (a basic text on planetary atmospheres).