Vision and Voyages for Planetary Science in the - Solar System ...

essential to planetary astronomical observations, both in support of active space missions and in
studies independent of (or as follow up to) such missions. Their continued support is critical to
the advancement of planetary science.
Large Synoptic Survey Telescope
One of the future NSF-funded facilities most important to planetary science is the Large
Synoptic Survey Telescope (LSST), a 6.5m wide-field survey telescope that will image the entire sky
visible from its observing site in Chile in six wavebands some 1000 times in a period of 10 years.
LSST will discover many small bodies in the solar system, some of which will require follow-up
observations for the study of their physical properties. Some of these bodies are likely to be attractive
candidates for future spacecraft missions. The potential for finding new populations of small bodies
that are presently unknown but which will further illuminate the dynamical history of the solar system
is especially exciting. The LSST will play a potentially critical role in completing the George E.
Brown survey of all near-Earth asteroids down to a diameter of 140 m (mandated by the Congress),
especially in the absence of a space-based infrared survey telescope optimized for this purpose. The
nominal schedule for the LSST calls for a two-year commissioning phase starting in mid-2016, and
the beginning of the 10-year operational phase in mid-2018. The committee encourages the timely
completion of LSST, and stresses the importance of its contributions to planetary science, as
well as astrophysics, once telescope operations begin.
Extremely Large Telescopes
With apertures of 30 meters and larger, ELTs will play a significant future role in planetary
science. Among the advantages of such telescopes is improved spatial resolution at mid-infrared and
longer wavelengths where planetary observations are impaired by the diffraction limit; even 8- to 10meter
telescopes have difficulty with the small angular sizes of Uranus and Neptune. Observations
using a 30-meter telescope could, for example, resolve thermal emission from Neptune with about the
same resolution as the 3-meter IRTF can for Saturn at the same wavelength, and give compositional
information on a large number of trans-Neptune objects. International efforts for ELT development
are proceeding rapidly, with at least three such telescopes in planning stages: the Giant Magellan
Telescope (GMT); the Thirty-Meter Telescope (TMT), and the European Extremely Large Telescope.
The committee does not provide specific guidance to NSF on this issue. It endorses the
recommendations and support for these facilities made by the 2010 Astronomy Decadal Survey
and encourages NSF to continue to invest in the development of ELTs, and to seek partnerships
to ensure that at least one such facility comes to fruition with some public access. The
committee believes that it is essential that the design of ELTs accommodate the requirements of
planetary science to acquire and observe targets that are moving, extended, and/or bright, and
that the needs of planetary mission planning be considered in awarding and scheduling public
time for ELTs. The earliest possible date NSF can seek approval from the National Science Board to
provide partial support to either the GMT or TMT project is 2014.
Small Telescopes
Small telescopes are also very useful for some solar system problems; amateurs with their
personal telescopes are playing an increasing role in laying groundwork for professionals. The 2009
and 2010 Jupiter impacts were discovered by amateurs who alerted the professional community, and
within hours of each event, observatory telescopes around the world were being mobilized for follow-
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