PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM ^TEXT = "AAREADME.TXT" OBJECT = TEXT PUBLICATION_DATE = 2019-04-25 NOTE = "AAREADME.TXT describes this volume." END_OBJECT = TEXT END Volume DWNC7FC1_1A Dawn Framing Camera 1 Raw Level-1A Ceres XM07 Archive ============================================================================== Brief Disk Description ============================================================================== This volume contains raw level-1A (EDR) Framing Camera 1 images from Dawn Ceres eXtended Mission 2 Orbit 7 (XMO7) or Ceres Extended 2 Elliptical (C2E) phase (2019-06-09 to 2018-10-31). NOTE: Reading the Science Plan (located in the /DOCUMENTS/SCIENCE_PLAN directory) is critical to the understanding of the Ceres observations and science objectives. Other critical documentation in the DOCUMENT directory include the volume SIS and calibration procedure. This EDR dataset is the primary record of image data as it was received on Earth. The images in this dataset have not been processed in any way other than by decompressing, extracting header information, and generating and attaching PDS labels. All images are stored in the 'DATA' branch of the directory tree. The data are provided in both PDS Image (IMG) and FITS formats. Anciliary information is stored within the image headers for the IMG, and in detached PDS labels for the FITS files. EDR image files (.IMG) contain as many as 5 PDS IMAGE objects, one of which describes the illuminated portion of the CCD and others that describe the pre/post scan and other dark elements (See SIS for details). The FITS files that are provided here only include a single image, that being the illuminated portion of the CCD. This volume includes individual dark and calibration lamp images. These images are the inputs to the composite calibration files which are needed for further processing of the raw images. The composite calibration files are archived as part of the DAWN-CAL-FC1-2-EDR-CALIB-IMAGES-V1.0 data set. Please refer to the calibration data set catalog for a discussion of which files should be used for each activity. More information describing the image and volume format is contained in the Software Interface Specification (SIS). A copy of the SIS is provided in the /DOCUMENT/SIS directory of this volume. SPICE kernels are archived by the NAIF Node of the PDS. 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. ============================================================================== Image File Naming Convention ============================================================================== Convention: FCxllimageid_yydddhhmmssFnz.IMG Example: FC11A0003923_11223174143F1A.IMG Where: FCx indicates the instrument (FC1) ll indicates the data processing level (1A) IMAGEID image id (7 characters, zero-padded - 0003923) yyddd indicates the image acquisition year/doy (11223) hhmmss indicates the image acquisition SCET (UTC - 174143) Fn n indicates the filter number used in capturing the image (F1) z indicates the data file version (A-Z - A) Note that in instances (like spacecraft safings, etc.) where the Framing Camera powered off without being able to store the last image number used, images were generated with duplicate image numbers. In order to eliminate the duplication 3,000,000 was added to the image number in the ground processing (e.g. a duplicate image number 0014325 would become image number 3014325). As a result consecutive images may not always have consecutive image numbers. ============================================================================== Volume Set Information ============================================================================== This volume is part of the Framing Camera 1 raw level-1A EDR images volume set. This volume set includes the following volumes: Volume ID Description ------------------------------------------------------- DWNXFC1_1A Dawn FC1 L1-A EDR cruise images DWNCFC1_1A Dawn FC1 L1-A EDR Ceres extended mission 1 images DWNC6FC1_1A Dawn FC1 L1-A EDR Ceres extended mission 2 XMO6 images DWNCF7C1_1A Dawn FC1 L1-A EDR Ceres extended mission 2 XMO7 images DWNCALFC1 Dawn FC1 calibration images ============================================================================== Mission Facts ============================================================================== The 'Dawn Science Observations' table below provides a list of scientific observations made by the Dawn instruments. It includes the observation start date, the ID of the phase in which it occurred, the activity name, and a brief description. Footnotes describing the availability or organization of specific data from specific observations are located at the end of this table and are indicated in the Activity Description by numbers in square brackets. For all of the prime mission and the early extended mission at Ceres, there were no science observation made with FC1. This instrument was designated as redundant hardware for a critical flight component. However, when the Ceres opposition (zero phase) observation was being planned it was clear that Dawn would only get one chance to acquire these images. In order to protect against a FC2 instrument reset or other failure, it was decided to operate both cameras simultaneously. Since this had never been done in flight, dual operation was initially tested at the end of CXG (Cycle 3) during RC4_NORTH_002. During the second extended mission at Ceres, FC1 was used to acquire images during the XMO6 and early part of the XMO7 orbits as a contingency against a loss of FC2 images that could result from a reset. The FC1 images were offset in time by a fixed amount from the FC2 images to avoid commanding collisions and to provide additional coverage when the downlink allowed images from both cameras to be returned. In general, less than half of of the images acquired could be returned in the available downlink. ============================================================================== Extended Mission 1 Science Observations with FC1 ------------------------------------------------------------------------------ Start Mission Activity Activity Date Phase Name Description ------------------------------------------------------------------------------ 16-12-14 CXG XMO3 Ceres Extended GRaND Phase (range ~8000-9500 km) ------------------------------------------------------------------------------ 17-02-19 CXG CYCLE3 307 FC2~nadir clear+color (1 orbit) 107 FC1~nadir clear+color ------------------------------------------------------------------------------ 17-04-28 CXO XMO4 Ceres Extended Opposition Phase (range 14-55 E3 km) ------------------------------------------------------------------------------ 17-04-29 CXO Opposition 205 FC2~nadir clear+color (range ~20,000 km) 199* FC1~nadir clear+color ============================================================================== Extended Mission 2 Science Observations with FC1 ------------------------------------------------------------------------------ 17-07-01 CX2 XMO5 Ceres Extended Mission 2 Phase (range ~15000 km) ------------------------------------------------------------------------------ 18-01-13 Checkout 65 of 65 non-pointed clear and color ------------------------------------------------------------------------------ 18-04-15 CTI TRANSFER_ Ceres Transfer to Intermediate Orbit TO_INTERMEDIATE ------------------------------------------------------------------------------ No FC science observations in this phase ------------------------------------------------------------------------------ 18-05-15 C2I XMO6 Ceres Extended 2 Intermediate (range ~1950 km) ------------------------------------------------------------------------------ 18-05-15 C2I XMO6 512 of 1349 nadir clear+color (3+ of 10 orbits) ------------------------------------------------------------------------------ 18-05-31 CTE TRANSFER_ Ceres Transfer to Elliptical Phase TO_ELLIPTICAL ------------------------------------------------------------------------------ No FC science observations in this phase ------------------------------------------------------------------------------ 18-06-09 C2E XMO7** Ceres Extended 2 Elliptical (peri altitude ~35 km) ------------------------------------------------------------------------------ 18-06-09 C2E da942 498 of 913 nadir clear only (5 orbits) 18-06-15 C2E da942 629 of 906 nadir clear only (5 orbits) 18-06-21 C2E da942 553 of 553 nadir Cerelia at Periapsis (3 orbits) 18-09-29 C2E Star Cal 128 of 128 images ------------------------------------------------------------------------------ * FC1 clear images were interleaved with the FC2 clear images by acquiring them at the same cadence (5 minutes) but offset in time 2.5 minutes later. FC1 color images were acquired inbound to minimum phase and FC2 images were acquired on the outbound leg providing functional redundancy while maximizing science return. ** FC1 images were interleaved with the FC2 images by images by acquiring them at the same cadence (5 minutes) but offset in time by 3 seconds. The image cadence at periapsis is 7 seconds. ============================================================================== File Formats ============================================================================== The image files on this volume are binary images. IMG files have an attached ASCII header (PDS label). The FITS versions have a detached PDS label. The PDS label contains information describing spacecraft, target, and imaging parameters characterizing the attached image. A data set description, instrument description, and other PDS documents are in .CAT files in the /CATALOG directory. 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. In Windows Explorer, open the 'Tools' menu and select 'Folder Options'. Select the 'File Types' tab and select 'CAT' from the list. Press 'Change...' and then choose your prefered text editor or viewer. We do not know of any harmful effects this might have on the operating system or other programs, but do not guarantee it will be entirely safe to make this change. If problems occur, the change can be undone in the same 'File Types' window by changing the default application back to 'crypto shell extension'. Additional documentation is generally located in the DOCUMENT directory. ============================================================================== Errata ============================================================================== Every effort has been made to assure 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. DWNC7FC1_1A (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. | | |- [CATALOG] PDS catalog files containing information describing the | data, instrument, instrument personnel, relevant references, | the spacecraft, and mission. | |- [BROWSE] JPG thumbnail versions of the images provided in DATA area. | |- [DATA] Contains the images in both PDS IMG, and FITS format. The | images are divided up into separate subdirectories by | observation activity, and date. | |- [DOCUMENT] Contains documents describing the instrument, and use of the | images | |- [INDEX] Contains a table of contents for all files located on this | volume, and the volume set to date. | |- [GEOMETRY] Contains a SPICE metakernel created by the Framing Camera Team to describe the time-varying instrument alignment. This is not a NAIF product. ============================================================================ Contacts ============================================================================ This volume was produced for the Planetary Data System (PDS) at the Small Bodies node. The images, and associated metadata were supplied by Pablo Gutierrez-Marques, and Joachim Ripken at the Max-Planck Institute for Solar System Research (MPS). The volume was assembled at the Dawn Science Center (DSC), by Joseph N. Mafi. For questions or problems regarding the volume, please contact Dr. 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 Pablo Gutierrez-Marques at MPS: Email gutierrez@mps.mpg.de Telephone +49 (0) 5556 979 313 Mail Max Planck Institute for Solar System Research Justus-von-Liebig-Weg 3, 37077 Gottingen, 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.