Using Reprojections to Examine Mercury's Surface
June 2, 2009
- Date Acquired: October 6, 2008
- Image Mission Elapsed Time (MET): 131766501
- Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
- Resolution: 450 meters/pixel (0.28 miles/pixel)
- Scale: This crater is about 200 kilometers (124 miles) in diameter
- Spacecraft Altitude: 16,300 kilometers (10,100 miles)
Of Interest: The scarp cutting through this crater was imaged as MESSENGER approached the planet during the mission's second Mercury flyby. The full NAC image acquired by MDIS is shown in a previous release while the image shown here is a reprojected view. Compare the two images to see the differences.
By using very precise knowledge about the time that the image was taken and the location of the spacecraft at that time, the original image can be mapped onto a globe of Mercury. Once mapped onto a Mercury globe, that globe can be viewed in many different ways, including reprojections that create flat maps of Mercury's surface, as seen in this global map of Mercury. The reprojected image shown here is from a simple cylindrical map projection. Map projections are needed to measure accurately the extent of features on the surface. For example, from this reprojection it was determined that this scarp is about 1 kilometer (0.6 miles) high and over 160 kilometers (100 miles) in length. MESSENGER Science Team members recently published an image similar to this reprojection in Science magazine.
Topics: Disaster Accident, Environment, Discovery program, MESSENGER, Mercury spacecraft, 2008, Mercury, Spaceflight