WASHINGTON, April 6 (Xinhua) -- A 52-km cable was put in place along the sea floor of California's Monterey Bay, marking an important step in the construction of a deep-sea observatory off the United State's continent.

    The cable will power scientific instruments, video cameras and robots 3,000 feet (900 meters) below the ocean surface. It will also relay data to land, which will be shared by scientists and engineers around the world, said the National Science Foundation (NSF) on Friday.

    The Monterey Accelerated Research System (MARS) observatory, when completed later this year, could allow scientists to monitor and control instruments 24 hours a day and have an unprecedented view of how environmental conditions in the deep sea change over time.

    Almost all the oceanographic instruments in the deep sea rely currently on batteries for power and the data stored in their hard disks or memory chips can be acquired only after they are brought back to land. With a continuous and uninterrupted power supply, instruments attached to the MARS observatory could remain on the sea floor for months or years.

    "MARS represents the first step in a long-planned process to transform the way the oceans are studied," said Julie Morris, director of NSF's Division of Ocean Sciences. "Marine scientists will no longer be required to go out to the ocean for their studies. The ocean is about to come into their offices."

    The cable, most of which is buried about 3 feet (about 0.9 meter) below the sea floor, will not be disturbed by boat anchors or fishing gears.

    "After five years of hard work, we are thrilled to bring the age of the Internet to the deep ocean, so we can understand, appreciate and protect the two-thirds of our planet that lies under the sea," said Marcia McNutt, director of Monterey Bay Aquarium Research Institute.

    The MARS project, initiated in 2002, receives a fund of 8 million U.S. dollars from NSF and 1.75 million dollars from the David and Lucille Packard Foundation.