Bibcode
Doyle, Laurance R.; Dunham, Edward T.; Deeg, H. J.; Blue, J. Ellen; Jenkins, Jon M.
Referencia bibliográfica
Journal of Geophysical Research, Volume 101, Issue E6, p. 14823-14830
Fecha de publicación:
1996
Número de citas
13
Número de citas referidas
10
Descripción
The detection of terrestrial-sized extrasolar planets from the ground
has been thought to be virtually impossible due to atmospheric
scintillation limits. However, we show that this is not the case for
specially selected (but nevertheless main sequence) stars, namely small
eclipsing binaries. For the smallest of these systems, CM Draconis,
several months to a few years of photometric observations with 1-m-class
telescopes will be sufficient to detect the transits of any short-period
planets of sizes >=1.5 Earth radii (RE), using
cross-correlation analysis with moderately good photometry. Somewhat
larger telescopes will be needed to extend this detectability to
terrestrial planets in larger eclipsing binary systems. (We arbitrarily
define ``terrestrial planets'' herein as those whose disc areas are
closer to that of Earth's than Neptune's i.e., less than about 2.78
RE.) As a ``spin-off'' of such observations, we will also be
able to detect the presence of Jovian-mass planets without transits
using the timing of the eclipse minima. Eclipse minima will drift in
time as the binary system is offset by a sufficiently massive planet
(i.e., one Jupiter mass) about the binary/giant-planet barycenter,
causing a periodic variation in the light travel time to the observer.
We present here an outline of present observations taking place at the
University of California Lick Observatory using the Crossley 0.9-m
telescope in collaboration with other observatories (in South Korea,
Crete, France, Canary Islands, and New York) to detect or constrain the
existence of terrestrial planets around main sequence eclipsing binary
star systems, starting with CM Draconis. We demonstrate the
applicability of photometric data to the general detection of gas giant
planets via eclipse minima timings in many other small-mass eclipsing
binary systems as well.