Bennu OSIRIS-REx OCAMS Global PAN Mosaic 5cm
- Primary Authors
- Lunar and Planetary Laboratory, University of Arizona
- Originators
- C.A. Bennett, D.N.DellaGiustina, K.J.Becker, T.L.Becker, K.L.Edmundson, D.R. Golish, et. al.
- Publisher
- USGS Astrogeology Science Center
- Publication Date
- 2020-02-26
- Abstract
-
In early 2019, NASA's OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and SecurityRegolith Explorer) mission surveyed asteroid (101955) Bennu with a collection of instruments, including the OSIRIS-REx Camera Suite (OCAMS) PolyCam imager. Using PolyCam panchromatic images, we constructed a globally controlled basemap of Bennu at an approximate ground sample distance of 5cm (5cm/pixel) with a mean spatial accuracy of ~30 cm. The basemap was photometrically normalized using a Minneart phase angle correction. New mapping methods were developed to combine images of Bennu's irregular shape and extremely rough surface into a nearly seamless mosaic. For more see Bennett (2020).
Highlights:
- We produced a global basemap of asteroid Bennu at a ground sample distance of 5 cm.
- New methods were developed to deal with Bennu's rough surface and irregular shape.
- Images were rectified to a 3D digital terrain model with a mean facet size of 80 cm.
- Images were photometrically normalized to 30° phase angle using a Minneart model.
- Overlaps were masked along natural feature boundaries for a nearly seamless result.
- PAN_mosaic_reflectance_32bit - this mosaic in 32bit floating point I/F (reflectance).
- BodyFixedXYZ - 3 images containing X,Y,Z in a body-fixed system per pixel in the original mosaic.
- EmisAngle_IncAngle_PixelRes - 3 images showing emission and incidence angles, and original pixel resolution.
- SunIlluminationMask - A simple image showing masked pixel map.
- Purpose
- As OSIRIS-REx is a sample return mission, a basemap is needed to identify a safe and sampleable location for the spacecraft's sample acquisition maneuver (Berry et al., 2013; Williams et al., 2018; Lauretta et al., 2017). Therefore, the global basemap must have sufficient resolution to clearly show geologic features including craters, ridges, boulders, and any other potentially hazardous objects.
Contact and Distribution
- Format
- Global Mosaic
- Access Constraints
- please cite authors
- Access Scope
- PDS
- Use Constraints
- public domain
- Edition
- FB34_FB56_ShapeV28_PAN
- Edition Name
- version:
- Supplemental Information
- https://www.sciencedirect.com/science/article/pii/S0019103520300816, https://sbn.psi.edu/pds/resource/orex/ocams.html, https://www.asteroidmission.org/
- Native Data Set Environment
- GDAL, ISIS v3
- Astrogeology Theme
- Asteroids, Cartography, Image Processing, Photogrammetry, Remote Sensing, Sampling and analysis
- Mission Names
- OSIRIS-REx
- Instrument Names
- OCAMS
- Online Package Link
- https://astrogeology.usgs.gov/search/map/bennu_osiris_rex_ocams_global_pan_mosaic_5cm
- External File Size
- 471 MB
- Online File Link
- https://planetarymaps.usgs.gov/mosaic/Bennu/Bennu_global_FB34_FB56_ShapeV28_GndControl_MinnaertPhase30_PAN_8bit.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)
- 2019-03-21
- Time Period of Content (stop)
- 2019-04-11
- Currentness Reference
- Ground condition
- Progress
- Complete
- Update Frequency
- As needed
- Logical Consistency
- This is a visual 8bit version of the original 32bit floating point version in I/F (reflectance). The mapping used to convert to 8bit was a linear stretch from 0.0 - 0.044 to 1 - 254, maintaining 0 as NoDATA.
- Completeness Report
- Most images that contribute to the global panchromatic basemap were acquired during Flybys 3, 4A, and 4B. Select data from Flybys 5A and 6A were also incorporated to provide better coverage in high-latitude regions that were poorly illuminated in the earlier flybys.
- Process Description
- OCAMS images were photogrammetrically controlled to correct for spacecraft position and camera pointing uncertainties in reconstructed SPICE kernels. This process improved the registration between the images and the DTM ("image-to-ground") and between the images themselves ("image-to-image"). Image features were manually registered to the DTM to create ground control points (GCPs). see the reference Bennett 2020 above.
- Source Title
- OSIRIS-REx PDS archive
- Source Online Linkage
- https://sbn.psi.edu/pds/resource/orex/
- PDS Status
- PDS 3 Compatible
- Attribute Accuracy Report
- Best Effort
- Horizontal Positional Accuracy Report
- Accurate to Control Net
Geospatial Information
- Target
- Bennu
- 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)
- 15709
- Raster Column Count (samples)
- 31417
- Bit Type (8, 16, 32)
- 8
- Quad Name
- Radius A
- 250
- Radius C
- 250
- Control Net
- ShapeV28
- Bands
- 1
- Pixel Resolution (meters/pixel)
- 0.05
- Scale (pixels/degree)
- 87.266
- Map Projection Name
- Equirectangular
- Latitude Type
- Planetocentric
- Longitude Direction
- Positive East
- Longitude Domain
- 0 to 360
