 |
| Titel |
Airbursts as a viable source of seismic and acoustic energy for the 2016 InSight geophysical lander mission to Mars: analysis using terrestrial analogues |
| VerfasserIn |
Jennifer Taylor, James Wookey, Nick Teanby |
| Konferenz |
EGU General Assembly 2014
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250089442
|
| Publikation (Nr.) |
 EGU/EGU2014-3644.pdf |
|
|
|
|
|
| Zusammenfassung |
| The explosion of a bolide as a terminal airburst, before impact into a planetary surface, is a
well-documented source of both seismic and acoustic energy[1]. Here we aim to define some
diagnostic properties of a recorded airburst time-series and determine detectability
criteria for such events for a single station seismo-acoustic station on the Martian
surface.
In 2016 NASA will launch the InSight geophysical monitoring system. This lander will
carry in its SEIS payload two 3-component seismic instruments – the Short Period (SP) and
Very Broadband (VBB) seismometers, as well as a micro-barometer for measurement of
atmospheric pressure fluctuations. The SEIS and MB packages aboard InSight could
potentially be used together for seismo-acoustic detection of impact or airburst
events.
In past studies, this technique has been used to analyse and model the Washington State
Bolide[2] and, more recently, the Chelyabinsk fireball in 2013[3]. Using a multi-station array,
it is possible to estimate total kinetic energy of a bolide, its line-of-sight direction and the
approximate time of its terminal burst[4]. However, with only a single station, as would be the
case on Mars, more creative methods must be employed to extract information from the
event.
We explore the diagnostic waveform properties of an airburst, including various
arrivals from the event. We also show how dominant frequency changes with distance
from the event, altitude and yield. Several terrestrial events are analysed, including
the 2013 Chelyabinsk fireball. We present theoretical calculations of the likely
proportion of bolide terminal bursts on Mars relative to impacts, based on differences in
the structure and composition of the Martian atmosphere. We go on to predict the
seismic arrivals that may be observed by InSight from the coupling of the acoustic
blast into the Martian crust. It is hoped that these diagnostic tools will be useful to
identify and quantify bolide terminal bursts on Mars over the course of the InSight
mission.
[1] - Edwards, Wayne N., Peter G. Brown, and David W. Eaton. "Frequency-Dependent
Acoustic–Seismic Coupling of Meteor Shock Waves."Bulletin of the Seismological Society
of America99.5 (2009): 3055-3066.
[2] - Arrowsmith, Stephen J., et al. "A joint seismic and acoustic study of the Washington
State bolide: Observations and modeling."Journal of Geophysical Research: Atmospheres
(1984–2012)112.D9 (2007).
[3] - Tauzin, Benoit, et al. "Seismo-acoustic coupling induced by the breakup of the 15
Feb 2013 Chelyabinsk Meteor."Geophysical Research Letters(2013).
[4] - Brown, Peter G., et al. "An entry model for the Tagish Lake fireball using seismic,
satellite and infrasound records."Meteoritics & Planetary Science37.5 (2002): 661-675. |
|
|
|
|
|
|