DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Unsupervised classification of Mercury’s Visible Near-Infrared MASCS/MESSENGER reflectance spectra for automated surface mapping

D'Amore, Mario and Helbert, Jörn and Maturilli, Alessandro and Varatharajan, Indhu (2021) Unsupervised classification of Mercury’s Visible Near-Infrared MASCS/MESSENGER reflectance spectra for automated surface mapping. EGU General Assembly 2021, 19–30 April 2021, Virtual. doi: 10.5194/egusphere-egu21-2661.

[img] PDF

Official URL: https://meetingorganizer.copernicus.org/EGU21/EGU21-2661.html


surface of Mercury has been mapped in the 400–1145 nm wavelength range by the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) instrument during orbital observations by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Under the hypothesis that surface compositional information can be efficiently derived from spectral reflectance measurements with the use of machine learning techniques, we have conducted unsupervised hierarchical clustering analyses to identify and characterize spectral units from MASCS observations. We apply our analysis on the latest MESENGER data delivery to PDS including the new spectral photometric correction , finding result consistent with our previous analysis based on our custom photometric effect removal. The input is a global hyperspectral data cube image of normalized MASCS visible (VIS) detector spectra, from the first Earth year of the orbital mission. Data coverage varies from region to region, but global maps at 1 degree/pixel can be obtained with a high signal-to-noise ratio (SNR). The resultant hyperspectral map was then visually inspected to search for anomalies that originated mainly in regions of low coverage or from high levels of spectral variation within a single pixel. Our approach consist of several steps: 1. Data cleaning step: remove data artifact. 2. Independent Component Analysis (ICA): features compression and undelyng signal demixing. 3. Manifold learning : embedding of data in a low dimensional space via UMAP. 4. Hierarchical clustering : creation of spectrally similar partition and projection on the surface with comparison to existing human generated classifications. We found the existence of two large and spectrally distinct regions, which we call the polar spectral unit (PSU) and the equatorial spectral unit (ESU). The spatial extent of the polar unit in the northern hemisphere generally correlates well with that of the northern volcanic plains. Further analysis indicates the presence of smaller sub-units that lie near the boundaries of these large regions and may be transitional areas of intermediate spectral characters.

Item URL in elib:https://elib.dlr.de/141965/
Document Type:Conference or Workshop Item (Speech)
Title:Unsupervised classification of Mercury’s Visible Near-Infrared MASCS/MESSENGER reflectance spectra for automated surface mapping
AuthorsInstitution or Email of AuthorsAuthor's ORCID iD
D'Amore, MarioMario.DAmore (at) dlr.dehttps://orcid.org/0000-0001-9325-6889
Helbert, JörnJoern.Helbert (at) dlr.dehttps://orcid.org/0000-0001-5346-9505
Maturilli, AlessandroAlessandro.Maturilli (at) dlr.dehttps://orcid.org/0000-0003-4613-9799
Varatharajan, IndhuIndhu.Varatharajan (at) dlr.deUNSPECIFIED
Date:April 2021
Refereed publication:No
Open Access:Yes
Gold Open Access:No
In ISI Web of Science:No
DOI :10.5194/egusphere-egu21-2661
Keywords:Unsupervised, classification,fMercury, Near-Infrared, MASCS,MESSENGER reflectance, spectra, automated , surface mapping
Event Title:EGU General Assembly 2021
Event Location:Virtual
Event Type:international Conference
Event Dates:19–30 April 2021
Organizer:EGU european geosciences union
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Exploration
DLR - Research area:Raumfahrt
DLR - Program:R EW - Space Exploration
DLR - Research theme (Project):R - Project BepiColombo - MERTIS and BELA
Location: Berlin-Adlershof
Institutes and Institutions:Institute of Planetary Research > Planetary Laboratories
Deposited By: Amore, Dr. Mario
Deposited On:26 May 2021 11:42
Last Modified:26 May 2021 11:42

Repository Staff Only: item control page

Help & Contact
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.