Transcript Imaging Mercury surface

Imaging Mercury surface
The SIMBIO-SYS Experiment for
the BepiColombo Mission
Enrico Flamini – Roma 27-2-07
IAS
orsay
SIMBIO-SYS
• SIMBIO-SYS is an integrated
package for the imaging and
spectroscopic investigation of the
Hermean surface selected by ESA
as part of the European mission to
Mercury BepiColombo .
SCIENCE: Geology and Geomorphology
– Geomorphological characterization
of the highly cratered units (3D)
– Origin, limit and areal extension of
intracrater, hummocky and smooth
plains;
– Stratigraphic relationships between
highlands and plains (3D)
– Presence of layered units (HR)
– Characterization of polar deposits;
– Identification of aeolian deposits;
– Impact crater morphologies and
degradation level (3D)
– Ejecta distribution and modification
100 km
15 km
Upper crust evolution and surface processes
SCIENCE: Volcanism Styles and
Deposits
– Origin of the smooth plain materials (volcanic or
lobate crater ejecta?); (3D + HR + IR)
– Identification of volcanic edifices; (3D)
– Identification of volcanic deposits (i.e. lava flow vs.
ejecta blanket); (3D + HR + IR)
– Definition of the type of volcanism (i.e. fissural,
explosive)
Interior dynamics and crustal differentiation processes
Discovery Scarp
Tectonics Evolution
–
Morphological characterization of mercurian
large lobate scarps; (3D)
– Identification and classification of smaller
tectonic features; (3D)
– Observation of cross-cutting relationships to
infer the relative age of tectonic events; (HR)
– Mapping the distribution of tectonic features
Crustal dynamics
40 km
Surface Age
– Observation of impact craters with diameter > 0.5 km;
– Mapping the different crater distribution;
– Comparison between age and the main geological units of highlands
and plains
– This would led to the definition of the impact flux in the inner Solar
System
Temporal occurrence
of geologic processes
30 km
Surface Composition and
Weathering
–
–
–
–
–
–
Characterization of the bulk surface composition;
Measure the FeO and TiO2 abundances;
Identification of recent volcanic deposits
Different composition of hermean plains respect to highlands
Identification of weathering products
Effect of surface weathering as function of the surface exposure (age)
Interior differentiation, alteration processes
Characterisation of Polar
deposits
–
Characterization of the polar deposits composition;
– Search for similar deposits in permanently shadowed
areas of large impact crater.
Radar bright spots
Water in coldest sites
SIMBIO-SYS Science
Summary
-
Surface geology: stratigraphy, geomorphology
– Volcanism: lava plain emplacement, volcanoes identification
-
Global tectonics: structural geology, mechanical properties of
lithosphere
-
Surface age: crater population and morphometry, degradation
processes
-
Surface composition: maturity and crustal differentiation,
weathering, rock forming minerals abundance determination
-
Geophysics: libration measurements, internal planet dynamics
SIMBIO-SYS Configuration
HRIC
STC
VIHI
SYMBIO-SYS, realised for the Italian
Space Agency by Galileo Avionica with
the partnership of France and Suisse,
incorporates capabilities to perform:
• medium space resolution global
mapping in stereo and colour
imaging using two pan-chromatic
and 3 broad-band filters Stereo
Channel STC;
• high spatial resolution imaging in
a pan-chromatic and 3 broad-band
filters High Resolution Imaging
Channel HRIC;
• imaging spectroscopy in the
spectral range 400  2000 nm
Visible Infrared Hyperspectral
Imager VIHI.
High spatial Resolution Imaging Channel
(HRIC)
Main Objectives
•
to provide images at ground pixel size of 5 m /pxl @ 400 km*
•
to provide high spatial coverage if about 20% Mercury surface
•
to provide high spatial resolution images in up to 4 different bands
Type of Optics
Catadioptric: Ritchey-Chretien with corrector
Type of Camera
Matrix Scanner
FOV
1.47 degrees
IFOV
12.5 rad
Spectral range
400 – 900 nm
Spectral Channels
Panchromatic(650) + 550, 700, 880 nm
Sensor type
APS 2048x2048
*The proposed thermal design of interfaces with the S/C could lead to the reduction
of the optics aperture and to a resolution of 10 m @ 400 km.
Saptial resolution: HRIC
20.0
18.0
16.0
ground resolution (m)
14.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0
-90
-70
-50
-30
-10
10
latitude (deg)
30
50
70
90
Ground track and Coverage: HRIC Peri-Herm
Ground track and coverage
100
80
60
40
latitude (deg)
20
0
-3
-3
-2
-2
-1
-1
0
1
1
2
-20
-40
-60
-80
-100
Longitude (deg)
HRIC FOV tracks for two consecutive (red and blue) orbits of the spacecraft. Peri-herm side
(adjacent tracks do not overlap at equator).
2
Ground track and Coverage: HRIC Apo-Herm
Ground track and coverage
100
80
60
40
latitude (deg)
20
0
177
178
178
179
179
180
180
181
181
182
182
-20
-40
-60
-80
-100
Longitude (deg)
HRIC FOV tracks for two consecutive (red and blue) orbits of the spacecraft. Apo-herm side
(adjacent tracks overlap).
Stereo Channel
(STC)
Main Objectives
1. Global mapping in stereo mode at spatial resolution of < 110 m
2. Global mapping in three colours at spatial resolution of < 110 m
Type of Optics
Petzval Design
Type of Camera
Matrix Scanner
FOV
4º (32mrad)
IFOV
23arcsec (111 rad)
Spectral range
500 – 900 nm
Spectral Channels
2xPanchromatic(650) + 550, 700, 880 nm
Sensor type
APS 2048x2048
Visible Infrared Hyperspectral Imager
channel (VIHI)
Main Objectives
1. To produce global mineralogical mapping at spatial resolution <400 m
2. To identify mineralogical species at a 5-10% confidence level
3. To correlate surface composition and surface features at a scale of
400m globally and up to 100m in selected places (> 5% surface
coverage)
Type of Optics
Schmidt Telescope; Littrow spectrometer
Type of Camera
Pushbroom spectrometer
FOV
3.7º (64mrad)
IFOV
50arcsec (250 rad)
Spectral range
400 – 2000 nm
Spectral
sampling
6.25 nm
Sensor type
HgCdTe with HgCdZn substrate removal;
256x256 CMOS ROIC; 30m pixel pitch
Optics Thermoelastic stability
Still under study: optomechanical tollerances not yet fixed. The
following values present have to be considered as reference.
APE Absolute Pointing
error;
Resource
Requirements: Pointing & Alignment
Parameter
IFOV
AME
HRIC
2.6
10
APE
RPE
6 (1.5*)
0.25 / 3.5
(jitter)
17 (short term)
RPE
*:
**:
***:
STC
23
6**
(¼ of a STC
pixel)
41 - 62
6/5
VIHI
52
12.5***
(¼ of a VIHI
pixel)
3
12.5 / 10
optimised for data volume
goal value, minimum requirement is 10 arcsec
goal value, minimum requirement is 20 arcsec
(units)
arcsec
arcsec
arcmin
arcsec / ms
arcsec / s
is driving STC+VIHI
AME
The in flight calibration it is of paramount importance for the removal
of thermomechanical biases!