PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM ^TEXT = "AAREADME.TXT" OBJECT = TEXT PUBLICATION_DATE = 2017-06-22 NOTE = "AAREADME.TXT describes this volume." END_OBJECT = TEXT END Volume DWNCLCFC2_2 Version 2 Dawn FC2 Ceres Encounter LAMO Clear Filter Mosaics Data Set DAWN-A-FC2-5-CERESMOSAIC-V1.0 ============================================================================== Brief Disk Description ============================================================================== This volume is one of three volumes that contain Ceres image mosaics. It includes various Ceres global and quadrangle mosaics derived from clear images acquired by the Framing Camera 2 (FC2) on the NASA Dawn spacecraft during the low altitude mapping orbits (LAMO). Global mosaics are provided in equidistant cylindrical and stereographic projections. Mercator and Lambert conformal projections are used for the equatorial and mid-latitude quadrangle mosaics respectively. The other volumes contain the remainder of the data set (HAMO color global mosaics and HAMO clear global mosaics, quadrangles, and atlas). This is the 2nd release of this volume (version 2). This version includes a 62 tile LAMO atlas (DOCUMENT/LAMO_ATLAS_62/*.PDF) that was not available at the time of the initial release. Dawn mission is equipped with two identical framing cameras (FC1 & FC2) [SIERKSETAL2011] which have one clear filter and seven band pass filters. At Ceres, only the FC2 was used to acquire science images while the FC1 was held in reserve. Clear filter images which were taken during HAMO were used to produce a global mosaic of the illuminated part of Ceres with a resolution of ~140 m/pixel [ROATSCHETAL2016]. Dawn orbited Ceres in 6 cycles between the middle of August and the middle November, 2015. A cycle is a single complete mapping of surface at a fixed attitude. The framing camera took about 2490 clear filter images with a the HAMO mapping phase. The images were taken with different viewing angles and different illumination conditions in order to provide input to the stereo-photogrametric [PREUSKERETAL2016] and stereo-photoclinometric analysis of the Ceres topography. All 386 images from the first cycle, plus a few from the second cycle to fill gaps, were used to to produce a global mosaic of Ceres with a resolution of 140 m/pixel, along with a 15-tile atlas at a scale of 1:750,000. In LAMO (low altitude mapping orbit), only clear filter images were acquired for the the first ~4 nadir mapping cycles. Later in LAMO, clear filter images were acquired at various off-nadir angles. Color imaging was limited to a few selected targets during off-nadir cycles because of data storage, downlink, and image smear limitations. At low Ceres altitude the combination of long exposures times and rapid Dawn motion relative to Ceres made smearing a significant concern for the various color filters while the clear filter smear was sub-pixel. No global or quadrangle mosaics can be created from the limited number of LAMO color images. NOTE: Reading the Science Plan (DOCUMENTS/SCIENCE_PLAN/DAWN_SCIPLAN_V5_4.PDF) is critical to the understanding of the planned Ceres observations and science objectives. The calibration procedure and files are identical to those applied to the Vesta data. There are several key publications that describe the data processing and image mosaicking. These include: ROATSCHETAL2016 Roatsch,T., E. Kersten,K.-D. Matz,F. Preusker, F. Scholten, R. Jaumann,C.A. Raymond, C.T.Russell, High-resolution Ceres High Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images, Planetary and Space Sciences, in press, 2016. PREUSKERETAL2016 Preusker,F., F. Scholten, K.-D Matz, S. Elgner, R.Jaumann, T. Roatsch, S.P. Joy, C.A. Polanskey, C.A. Raymond, and C.T. Russell, Dawn at Ceres - Shape model and Rotational State, Planetary and Space Sciences, in press, 2016. SCHROEDERETAL2013A Schroeder, S. E., T. Maue, P.Gutierrez-Marques, S. Mottola, K.M. Aye, H. Sierks, H.U. Keller, A. Nathues, A. In-fight Calibration of the Dawn Framing Camera. Icarus 226, p1304-1317, 2013. SCHROEDERETAL2013B Schroeder, S.E., S. Mottola, H.U. Keller, C.A. Raymond, C.T. Russell, Resolved photometry of Vesta reveals physical properties of crater regolith, Planetary and Space Sciences, 85, 198-213, 2013. SCHROEDERETAL2014 Schroeder, S.E., S. Mottola, K.-D. Matz, T. Roatsch, In-flight calibration of the Dawn Framing Camera II: Flat fields and stray light correction, Icarus, 234, 99-108. POLANSKEYETAL2016 Polanskey, C., S. Joy, and C. Raymond, "Dawn Ceres Mission: Science Operations Performance", SpaceOps 2016 Conference, SpaceOps Conferences, (in press). POLANSKEYETAL2012 Polanskey, C., S. Joy, and C. Raymond, "Efficacy of the Dawn Vesta Science Plan", SpaceOps 2012 Conference, SpaceOps Conferences, http://dx.doi.org/10.2514/6.2012-1275915. All data are stored in the 'DATA' branch of the directory tree. In addition to the data files, ancillary information is stored in an attached PDS label. Additional copies of the data in TIFF (Tagged Image File Format)format can be found in the EXTRAS directory of this volume. Some users may find this format easier to work with in some software packages such as ArcGIS. Users of these data are encouraged to acknowledge both the PDS and the principal investigators of the instruments whose data is used in analysis in all publications. ============================================================================== File Naming Conventions ============================================================================== Data and browse images on this volume conform to the following naming convention: CE_PHASE_T_LAT_LONG_PROJ_TYPE.EXT where: CE is literal for Ceres PHASE is either HAMO or LAMO T is either Q (quadrangle) or G (global) LAT is the center latitude of the image LONG is the center longitude of the image PROJ is the map projection type (CYL=cylindrical, STE=stereographic, LAM=Lambert, MER-Mercator) TYPE is the image type (CLR = clear filter 1, FILTx, X=1-8 is a single filter color mosaic) example: CE_LAMO_Q_00N_108E_MER_CLR.IMG Ceres LAMO quadrangle centered at 0N latitude, 108E longitude using a Mercator projection in the clear filter. ============================================================================== Volume Set Information ============================================================================== This volume is part of the FC2 high level data volume set. This volume set includes the following volumes: Volume ID Description ------------------------------------------------------------ DWNVFC2_2 Dawn FC2 L2/3 Vesta Encounter mosaics DWNVSPG_2 Dawn FC2 L2/L3 Vesta stereo-photogrammetric DTM DWNVSPC_2 Dawn FC2 L2/L3 Vesta stereo-photoclinometric DTM DWNCHCFC2_2 Dawn FC2 L2/3 Ceres HAMO clear mosaics DWNCHFFC2_2 Dawn FC2 L2/3 Ceres HAMO color filter mosaics ==> DWNCLCFC2_2 Dawn FC2 L2/3 Ceres LAMO clear mosaics DWNCHSPG_2 Dawn FC2 L2/L3 Ceres HAMO stereo-photogrammetric DTM DWNCHSPC_2 Dawn FC2 L2/L3 Ceres HAMO stereo-photoclinometric DTM DWNCLSPG_2 Dawn FC2 L2/L3 Ceres LAMO stereo-photogrammetric DTM DWNCLSPC_2 Dawn FC2 L2/L3 Ceres LAMO stereo-photoclinometric DTM ============================================================================== Mission Facts ============================================================================== The 'Dawn Ceres Science Phases' table below provides a list Dawn Ceres Encounter mission phase start dates. ------------------------------------------------------------------------------ Dawn Ceres Science Phases ------------------------------------------------------------------------------ start date (DOY) Phase Name (ID) ------------------------------------------------------------------------------ 2014-12-26 (360) CERES SCIENCE APPROACH (CSA) 2015-04-24 (114) CERES SCIENCE ROTATIONAL CHARACTERIZATION 3 (CSR) 2015-05-09 (129) CERES TRANSFER TO SURVEY (CTS) 2015-06-04 (155) CERES SCIENCE SURVEY (CSS) 2015-07-01 (182) CERES TRANSFER TO HAMO (CTH) 2015-08-17 (228) CERES SCIENCE HAMO (CSH) 2015-10-23 (296) CERES TRANSFER TO LAMO (CTL) 2015-12-16 (350) CERES SCIENCE LAMO (CSL) 2016-06-19 (171) End of prime mission ------------------------------------------------------------------------------ ============================================================================== File Formats ============================================================================== The data files on this volume are formatted as PDS images (.IMG, binary) with attached PDS3 labels. The PDS label contains information describing spacecraft, target, and data record format. Even though the PDS labels are attached to the files, they can be viewed in a text editor. A data set description, instrument description, and other PDS documents are in .CAT files in the /CATALOG directory. Additional documentation is generally located in the DOCUMENT directory. Note for Windows users: In more recent versions of the Microsoft Windows operating system the .CAT by default is reserved as 'Security Catalog.' The .CAT files contained in this volume are ASCII text files, and can be read by any form of text editor. To make Windows open files with this name extension as text files, do the following. To make Windows open files with this name extension as text files right click the .CAT file, select with and choose a text editor to open the file. ============================================================================== Errata ============================================================================== Every effort has been made to insure that the data and documentation are of the best possible quality. However, mistakes are inevitable. There is a file called ERRATA.TXT found at the root level of this volume which contains a list of known deficiencies or caveats associated with data on this volume at the time this volume was produced. ============================================================================== Volume Contents and Structure ============================================================================== This section describes the volume structure and naming conventions. Below is a tree diagram of the volume, followed by a description of the directory function and key files in each directory. DWNCLCFC2_2 (root directory) | |- AAREADME.TXT Describes volume contents, and organization (this file) | |- ERRATA.TXT Describes known deficiencies or caveats in the data or | on this volume. | |- VOLDESC.CAT High level description of volume contents. | |- [BROWSE] Contains a JPG images of the data located in the DATA branch | of this volume. More information on the contents of this | directory is provided in the file /BROWSE/BROWINFO.TXT. | |- [CATALOG] PDS catalog files containing information describing the | data, instrument, instrument personnel, relevant references, | the spacecraft, and mission. More information on the contents | of this directory is provided in the file | /CATALOG/CATINFO.TXT. | |- [DATA] Contains the data files. | |- [DOCUMENT] Contains documents describing the instrument, and data | acquisition, processing, and usage. More information on the | contents of this directory is provided in the file | /DOCUMENT/DOCINFO.TXT. | |- [EXTRAS] Contains files which facilitate the use of the data on the | disk, but which are not actually required for the use or | understanding of those data. A more detailed description of | the contents of this directory is provided in the file | /EXTRAS/EXTRINFO.TXT. | |- [INDEX] Contains a table of contents for all files located on this | volume, and the volume set to date. A more detailed | description of the contents of this directory is provided in | the file /INDEX/INDXINFO.TXT. ============================================================================ Contacts ============================================================================ This volume was produced for the Planetary Data System (PDS) at the Small Bodies node. The data, and associated metadata were supplied by Dr. Thomas Roatsch, DLR Berlin-Adlershof. The volume was assembled at the Dawn Science Center (DSC), by Joseph N. Mafi. For questions or problems regarding the volume, please contact Carol Neese at the PDS Small Bodies Node: Email neese@psi.edu Telephone 520-622-6300 Mail Carol Neese Planetary Science Institute 1700 E. Ft. Lowell, Ste. 106 Tuscon, AZ 85719-2395 USA For question regarding the data, please contact Dr. Thomas Roatsch of DLR: Email thomas.roatsch@dlr.de Telephone +49 30 67055-0 Mail DLR Berlin-Adlershof RutherfordstraBe 2 12489 Berlin Germany For questions regarding PDS Standards or other archives available from the PDS, please contact PDS Operator at the PDS Engineering Node (at JPL): Email pds_operator@jpl.nasa.gov Telephone 818-354-4321 Mail Planetary Data System, PDS Operator Jet Propulsion Laboratory Mail Stop 202-101 4800 Oak Grove Dr. Pasadena, CA 91109-8099 USA The PDS assumes no legal liability for errors on this disk. All users are encouraged to verify the correctness of the data prior to submitting any publications or other work based on these data. Please report errors on this disk to the Small Bodies Node of the PDS through the ERRATA reporting procedures described above.