Ceres Dawn FC2 HAMO Global DTM 137m

Primary Authors

German Aerospace Center (DLR)

Originators

Dawn Team

Publisher

USGS Astrogeology Science Center

Publication Date

2016-08-19

Abstract

Product Information: This digital terrain model (DTM) of Ceres based on the Dawn High Altitude Mapping Orbit (HAMO) Framing Camera 2 (FC2) images and derived by using the stereo photogrammetry (SPG) method. The HAMO DTM covers approximately 98% of Ceres surface (few permanently shadowed areas near the poles required interpolation). The DTM has a lateral spacing of ~136.7 meters per pixel (m) (60 pixel/degree) and a vertical accuracy of about 10 m. A global DTM is provided in an equidistant cylindrical projection and hemispheric DTMs are provided for both polar regions as stereographic projections. The DTMs are formatted as images where the DN values give the height in meters above a reference sphere of 470000.0m (Preusker et al., 2016). Mission and Instrument Information: The Dawn spacecraft launched on September 25, 2007 onboard a Delta II-Heavy Rocket. The instrument payload consisted of two identical framing cameras (FC1 & FC2), a visible and infrared mapping spectrometer (VIR, and a gamma ray and neutron detector (GRaND). DAWN is a National Aeronautics and Space Administration (NASA) Discovery Program mission managed by the Jet Propulsion Laboratory (JPL), with the principal investigator and science operations center located at the University of California, Los Angeles. The framing cameras were built by the Max Planck Institute for Solar System Research, with significant contributions by the German Aerospace Center, Institute of Planetary Research (DLR) and in coordination with the Institute of Computer and Communication Network Engineering (Polansky et al., 2016). Dawn spacecraft orbited Ceres in a series of science orbits designed to gradually increase the resolution and quality of science measurements as the mission at each target (Vesta & Ceres) progressed. The four science orbits are: rotation characteristic (RC) at 14,000 km, survey at 4,900 km, high altitude mapping orbit (HAMO) 1,950 km, and low altitude mapping orbit (LAMO) 850 km. HAMO provided the opportunity to collect data for the global topography model by collecting six complete clear-image maps: two at nadir and four at of nadir attitudes (Polansky et al., 2016). References: Polanskey, C., Joy, S., & Raymond, C. (2016). Dawn Ceres Mission: Science Operations Performance. Paper presented at the SpaceOps Conference, Daejeon, Korea. https://arc.aiaa.org/doi/abs/10.2514/6.2016-2442 Preusker, F., Scholten, F., Matz, K. D., Elgner, S., Jaumann, R., Roatsch, T., Joy, S. P., Polanskey, C. A., Raymond, C. A., & Russell, C. T. (2016). Dawn at Ceres - Shape model and rotational state. Paper presented at the 47th Lunar and Planetary Science Conference, Lunar and Planetary Institute, Houston, TX. http://www.hou.usra.edu/meetings/lpsc2016/pdf/1954.pdf Raymond, C. A., Jaumann, R., Nathues, A., Sierks, H., Roatsch, R., Preusker, F., Scholten, F., et al. (2011). The Dawn Topography Investigation. In Russell, C. & Raymond, C. (Eds.), The Dawn Mission to Minor Planets 4 Vesta and 1 Ceres (pp. 487-510). New York, NY: Springer. https://doi.org/10.1007/978-1-4614-4903-4_16 Roatsch, T., Kersten, E., Matz, K.-D., Preusker, F., Scholten, F., Jaumann, R., Raymond, C. A., & Russell, C. T. (2016). High-resolution Ceres High Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images. Planetary and Space Sciences, 125, 103-107. https://doi.org/10.1016/j.pss.2016.05.011

Purpose

Part of the PDS release of Ceres higher level data (Level 2). Ceres Digital Terrain Model - Certified and released with minor liens as of October 11, 2016. Dawn mission is equipped with two identical framing cameras (FC1 & FC2) 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 DTM of the illuminated part of Ceres [Preusker 2016]. Dawn orbited Ceres during in 6 cycles between August 16 and October 23, 2015 at the HAMO altitude of ~1475 km. A cycle is a single complete mapping of surface at a fixed attitude (nadir or off-nadir). The framing camera acquired about 2350 clear filter images [Preusker 2016] during the HAMO phase. The images were taken with different viewing angles and similar illumination conditions by slewing the spacecraft to various off-nadir attitudes. These images are analyzed by using the SPG method [Preusker 2016] to produce the Ceres HAMO DTM.

Contact and Distribution

Format

Digital Elevation Model, Grey Scale, Raster Data, Topographic Map

Access Constraints

None

Access Scope

PDS

Use Constraints

Please cite authors

Series Id

DWNCHSPG_2

Edition

1.0

Edition Name

DAWN-A-FC2-5-CERESHAMODTMSPG-V1.0

Supplemental Information

http://dawndata.igpp.ucla.edu/, http://www.sciencedirect.com/science/article/pii/S0032063312002589

Native Data Set Environment

ISIS v3

Astrogeology Theme

Asteroids

Mission Names

Dawn

Online Package Link

https://astrogeology.usgs.gov/search/map/ceres_dawn_fc2_hamo_global_dtm_137m

External File Size

446 MB

Online File Link

https://planetarymaps.usgs.gov/mosaic/Ceres_Dawn_FC_HAMO_DTM_DLR_Global_60ppd_Oct2016.tif

Contact Address

2255 N. Gemini Drive

Contact City

Flagstaff

Contact State

AZ

Contact Postal Code

86001

Contact Email

astroweb@usgs.gov

Data Status and Quality

Time Period of Content (start)

2014-12-26

Time Period of Content (stop)

2016-04-21

Currentness Reference

Ground condition

Progress

In Work

Update Frequency

As needed

Logical Consistency

The DTMs are formatted as images where the DN values give the height in meters above a reference sphere of 470000.0m. The conversion from Digital Number to PLANETARY_RADIUS in meters is: PLANETARY_RADIUS = pixel_DN + 470000.0m

Completeness Report

There were a few permanently shadowed areas near the poles required interpolation.

Process Description

The framing camera acquired about 2350 clear filter images [Preusker 2016] during the HAMO phase. The images were taken with different viewing angles and similar illumination conditions by slewing the spacecraft to various off-nadir attitudes. These images are analyzed by using the SPG method [Preusker 2016] to produce the Ceres HAMO DTM.

Lineage

Process Date

2016-08-16

Source Title

Dawn at Ceres - Framing Camera

Source Online Linkage

{https://sbn.psi.edu/pds/resource/dawn/dwncfcmosaics.html,https://sbn.psi.edu/pds/archive/maps.html}

Source PDS Archive

Dawn

PDS Status

PDS 3 Archived

Vertical Positional Accuracy Report

Best Effort

Geospatial Information

Target

Ceres

System

Small Bodies

Minimum Latitude

-90

Maximum Latitude

90

Minimum Longitude

0

Maximum Longitude

360

Direct Spatial Reference Method

Raster

Object Type

Grid Cell

Raster Row Count (lines)

10800

Raster Column Count (samples)

21600

Bit Type (8, 16, 32)

16

Quad Name

Radius A

470000

Radius C

470000

Bands

1

Pixel Resolution (meters/pixel)

136.7174581

Scale (pixels/degree)

60

Vertical Coordinate System Units

Meters

Map Projection Name

Equirectangular

Latitude Type

Planetocentric

Longitude Direction

Positive East

Longitude Domain

0 to 360