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| Titel |
EU-FP7-iMars: Analysis of Mars Multi-Resolution Images using Auto-Coregistration, Data Mining and Crowd Source Techniques: an overview and a request for scientific inputs. |
| VerfasserIn |
Jan-Peter Muller, Klaus Gwinner, Stephan van Gasselt, Anton Ivanov, Jeremy Morley, Robert Houghton, Steven Bamford, Vladimir Yershov, Panagiotis Sidirpoulos, Jungrack Kim |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250098103
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| Publikation (Nr.) |
 EGU/EGU2014-13744.pdf |
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| Zusammenfassung |
| Understanding the role of different planetary surface formation processes within our Solar
System is one of the fundamental goals of planetary science research. There has been a
revolution in planetary surface observations over the last 7 years, especially in 3D imaging of
surface shape (down to resolutions of 10cm) and subsequent terrain correction of imagery
from orbiting spacecraft. This has led to the ability to be able to overlay different epochs back
to the mid-1970s, examine time-varying changes (such as the recent discovery
of boulder movement [Orloff et al., 2011] or the sublimation of sub-surface ice
revealed by meteoritic impact [Byrne et al., 2009] as well as examine geophysical
phenomena, such as surface roughness on different length scales. Consequently
we are seeing a dramatic improvement in our understanding of surface formation
processes.
Since January 2004 the ESA Mars Express has been acquiring global data, especially
HRSC stereo (12.5-25m nadir images) with 87% coverage with images -¤25m and more than
65% useful for stereo mapping (e.g. atmosphere sufficiently clear). It has been demonstrated
[Gwinner et al., 2010] that HRSC has the highest possible planimetric accuracy of -¤25m and
is well co-registered with MOLA, which represents the global 3D reference frame. HRSC 3D
and terrain-corrected image products therefore represent the best available 3D reference data
for Mars.
NASA began imaging the surface of Mars, initially from flybys in the 1960s with the first
orbiter with images -¤100m in the late 1970s from Viking Orbiter. The most recent orbiter to
begin imaging in November 2006 is the NASA MRO which has acquired surface imagery of
around 1% of the Martian surface from HiRISE (at -20cm) and -5% from CTX (-6m) in
stereo. Unfortunately, for most of these NASA images, especially MGS, MO, VO and
HiRISE their accuracy of georeferencing is often worse than the quality of Mars
reference data from HRSC. This reduces their value for analysing changes in time
series.
Within the iMars project (http://i-Mars.eu), a fully automated large-scale processing (“Big
Data”) solution is being developed to generate the best possible multi-resolution DTM of
Mars co-registered to HRSC (50-100m grid) products generated at DLR from CTX (6-20m
grid, loc.cit.) and HiRISE (1-3m grids) on a large-scale linux cluster based at MSSL with 224
cores and 0.25 Pb of storage. The HRSC products are employed to provide a geographic
reference for all current, future and historical NASA products using automated co-registration
based on feature points and initial results will be shown. The metadata already available for
all orbital imagery acquired to date, with poor georeferencing information, has been
employed to determine the “sweet spots” which have long time series of measurements
with different spatial resolution ranges over the last -50 years of observations
and these will be shown. In 2015, as much of the entire NASA and ESA record of
orbital images will be co-registered and the updated georeferencing information
employed to generate a time series of terrain relief corrected orthorectified images
(ORIs) back to 1977. Web-GIS using OGC protocols will be employed to allow
exploration visually of changes of the surface. Data mining processing chains are being
developed to search for changes in the Martian surface from 1971-2015 and the output
of this data mining will be compared against the results from citizen scientists’
measurements in a specialised Zooniverse implementation. Final co-registered data
sets will be distributed through both European and US channels in a manner to be
decided towards the end of the project. The resultant co-registered image datasets will
represent the best possible capture of changes and evolutions in the Martian surface. A
workshop is planned to be held during the EGU time period to try to capture scientific
input on the relative priorities of different types of changes based on these “sweet
spots”.
Acknowledgements: The research leading to these results has received funding from the
European Union’s Seventh Framework Programme (FP7/2007-2013) under iMars grant
agreement n° 607379.
References: [1] Orloff et al. (2011) Boulder movement at high northern latitudes of Mars.
J Geophys Res-Planet, 116: E11006-1-12; [2] Byrne et al. (2009) Distribution of mid-latitude
ground ice on Mars from new impact craters. Science, 325: 1674-1676; [3] Gwinner, K., F. et
al. (2010) Topography of Mars from global mapping by HRSC high-resolution
digital terrain models and orthoimages: characteristics and performance. Earth and
Planetary Science Letters 294, 506-519, doi:10.1016/j.epsl.2009.11.007, 2010. |
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