Hot Topic: Dust and biomarkers from impacts on exoplanets
by
MrGianni Cataldi(Department of Astronomy, Stockholm University)
→
Europe/Stockholm
C61
C61
Description
We present preliminary results from our investigation of the
possibility of detecting dust generated in an impact event on an
exoplanet. Dust originating from an exoplanetary surface could
potentially give information on its composition, habitability or even
hint to the presence of life. Indeed, certain minerals or rocks (e.g.
granite) have been suggested as biomarkers. The direct detection of
microbial life ejected during the impact is also considered. We aim to
investigate whether any biomarkers could be detected within the debris
using spectroscopic observations.
We first estimate the amount of escaping mass for different impact
parameters (size and density of the impactor, size of the exoplanet,
etc.). We then assess the collisional evolution of the resulting
circumstellar debris belt with a simplified analytical model. Although
an exoplanetary atmosphere would prevent dust from escaping, dust can be
produced subsequently from mutual collisions of the larger debris. The
timescale for the belt to attain its brightest state as well as the
overall lifetime of the belt are estimated. The fractional luminosity of
the belt is calculated and compared to background noise such as
exozodiacal dust.