HAWAII MR1
Encyclopedia
The HAWAII MR1 is a seafloor imaging system developed by the Hawaii Mapping Research Group (HMRG) in 1991. HAWAII MR1 is short for HIGP (Hawaii Institute of Geophysics and Planetology) Acoustic Wide Angle Imaging Instrument, Mapping Researcher 1. This system is the first to use all-digital signal processing. It has been used in the discovery of several objects and locations of note, examples being the USS Yorktown
and the HMRG Deep
.
The HAWAII MR1 also has the capability to measure and collect bathymetric and backscatter
data simultaneously, and record raw acoustic data
independently of human supervision. After collecting data, the data can be processed with software available from HMRG.
The width of a scan produced by the system varies, depending upon whether it is producing a bathymetry swath or a sidescan swath; the swath while recording bathymetry data is 3.4 times the water depth and the swath while recording sidescan data is 7.5 times the water depth.
, the person who discovered the RMS Titanic. The goal of the expedition was to find the USS Yorktown, which they did successfully. Ballard said of the sonar, "It was the [University of Hawaii mapping team's sonar] that enabled us to find it." Bruce Appelgate, at the time director of field operations at HMRG, noted that they were fortunate in finding the ship, as it was at the very edge of the MR1's resolution. The ship was 17,000 feet (5.2 km) underwater.
The mapping system was also used in the discovery of the HMRG Deep, the second deepest spot in the world (after the Challenger Deep
).
USS Yorktown (CV-5)
was an aircraft carrier commissioned in the United States Navy from 1937 until she was sunk at the Battle of Midway in June 1942. She was named after the Battle of Yorktown in 1781 and the lead ship of the Yorktown class which was designed after lessons learned from operations with the large...
and the HMRG Deep
HMRG Deep
The HMRG Deep was discovered in 1997 by a team of scientists from Hawaii. Its depth is thought to be second or third only to the Challenger Deep and possibly Horizon Deep, currently the deepest known places in the ocean...
.
Description
The MR1 system is relatively small and stable, and is towed at a depth of 80 to 100 meters. Because it is not hull-mounted, this data collection system has the ability to withstand rough conditions.The HAWAII MR1 also has the capability to measure and collect bathymetric and backscatter
Backscatter
In physics, backscatter is the reflection of waves, particles, or signals back to the direction they came from. It is a diffuse reflection due to scattering, as opposed to specular reflection like a mirror...
data simultaneously, and record raw acoustic data
independently of human supervision. After collecting data, the data can be processed with software available from HMRG.
The width of a scan produced by the system varies, depending upon whether it is producing a bathymetry swath or a sidescan swath; the swath while recording bathymetry data is 3.4 times the water depth and the swath while recording sidescan data is 7.5 times the water depth.
Discoveries
The HAWAII MR1 was chosen to be used on an expedition headed by Robert BallardRobert Ballard
Robert Duane Ballard is a former United States Navy officer and a professor of oceanography at the University of Rhode Island who is most noted for his work in underwater archaeology. He is most famous for the discoveries of the wrecks of the RMS Titanic in 1985, the battleship Bismarck in 1989,...
, the person who discovered the RMS Titanic. The goal of the expedition was to find the USS Yorktown, which they did successfully. Ballard said of the sonar, "It was the [University of Hawaii mapping team's sonar] that enabled us to find it." Bruce Appelgate, at the time director of field operations at HMRG, noted that they were fortunate in finding the ship, as it was at the very edge of the MR1's resolution. The ship was 17,000 feet (5.2 km) underwater.
The mapping system was also used in the discovery of the HMRG Deep, the second deepest spot in the world (after the Challenger Deep
Challenger Deep
The Challenger Deep is the deepest known point in the oceans, with a depth of to by direct measurement from submersibles, and slightly more by sonar bathymetry . It is located at the southern end of the Mariana Trench near the Mariana Islands group...
).