NASA and exploratory research vessel Nautilus announced this week their mission may have discovered some meteorite fragments in the National Oceanic and Atmospheric Administration’s Olympic Coast National Marine Sanctuary, about 15 miles (25 kilometers) off the coast of Washington state. The remains are believed to be from the fall of a bright meteorite, called a bolide, that took place on March 7, 2018.
☄So...did we find meteorites in the ocean?☄— E/V Nautilus (@EVNautilus) 4 July 2018
After 7 hours exploring @OlympicCoast seafloor, we brought back several samples. @NASA_Johnson Cosmic Dust Curator Dr. Marc Fries conducted a visual analysis of these possible spacerocks--preliminary findings: https://t.co/hMCodJlZUR pic.twitter.com/iRUwud44Ud
NASA Cosmic Dust Curator Dr. Marc Fries had estimated that the fall was approximately 2 tonnes of meteorites, the largest ever observed in 21 years of radar data. The curator is now on board the expedition and has revealed some preliminary findings on the collected samples.
After an initial visual analysis, Fries deducted that the samples contained "two small fragments of fusion crust--meteorite exterior that melted and flowed like glaze on pottery as it entered the atmosphere." The coming weeks will see more research undertaken to determine if they originated from the massive meteorite fall.
The project is a cooperation of the Ocean Exploration Trust, the Olympic Coast National Marine Sanctuary, NASA, and the University of Washington. If the discoveries do end up being from the bolide fall, the mission will be the first known recovery of a meteorite from the ocean.
ROVs in use
The expedition was planned in June and, luckily, the Nautilus happened to be operating in the suspected crash area. The ship uses remotely operated vehicles called ROVs that can scan the seabed with cameras and special sensing instruments including a magnetic rod to detect metallic material.
The first ROV dive took place on July 2, 2018, and was broadcast live in real-time on Nautilus Live. The ship's ROVs, named Hercules and Argus, conducted a 7-hour visual survey of the suspected impact site's seafloor while the Nautilus team collected sediment samples.
It then took the team about six hours of sifting and processing in the ship’s wet lab to find the potential meteorite fragments. If confirmed to indeed be meteorite particles, the bits will be sent to the Smithsonian Institution in Washington, D.C. and incorporated in their research collections.
The Meteoritical Society, a non-profit scholarly organization founded in 1933 to promote the study of extraterrestrial materials, will then be in charge of determining whether there’s enough material in the samples to qualify as a meteorite. The organization records all known meteorites in its Meteoritical Bulletin.
The expedition will now continue to transit from Astoria to Sidney, BC using the ship's multibeam echosounder to perform high resolution mapping. The purpose of the mission will be for general bathymetric data collection and seafloor characterization through backscatter.
Via: Nautilus Live