In the coming decades, the
search for life beyond our Solar System will use astronomical
telescopes that are designed to obtain disk-averaged spectra of
terrestrial planets around other stars. The Virtual
Planetary Laboratory (VPL) is a suite of interdisciplinary computer
models developed to explore the environments and spectral appearance of
plausible terrestrial planets beyond our Solar System. This
presentation will focus on highlights of spectroscopic results to date
for terrestrial planet models from the VPL team. This includes studies
of disk-averaged modern-day Earth, the effect of different stellar
energy distributions on Earth-like planets, high-CO2 early atmospheres,
and the change in the spectroscopic appearance of the Earth over its
4.6Gy history. Using the model spectra, we will explore what
could be learned about extrasolar terrestrial planet habitability, or
the presence of life, using remote-sensing techniques. This
presentation will also describe how the synergistic combination of
information from several wavelength regions could be used to provide a
more robust determination of habitability and the presence of life.