Update: Recent MARS node installation and HV connector failure.
On Tuesday Feb 26th, the MARS node was installed into the Trawl Resistant Frame out on Smooth Ridge 32 kilometers (20 miles) from Moss Landing in 900 meters water depth (the TRF is attached to the shore cable that was installed in March 2007.) The ROV pilots and ships crew did an outstanding job launching the node, flying the node down to the TRF, lowering the node into the TRF, and connecting the node to the TRF/cable with the fiber and power connectors. This part of the operation went flawlessly. The system was then powered up to 7.25kV and the node booted up as expected. Then, 20 minutes after powering up the system, we experienced a failure of the high voltage (HV) connector between the MARS Cable Termination Assembly (CTA) and the HV power housing in the node. The cause of the HV connector failure is unknown at this time, although it may well be associated with the connector being underwater at pressure since the cable was laid approximately 12 months ago.
Because of this problem, the node was recovered on Thursday Feb 28th and the failed connectors removed and returned to the supplier for inspection and failure mode evaluation.
This is a unfortunate and disappointing setback to the MARS project and, of course, to all of the scientists planning on using MARS this year.
At minimum, the repair will involve replacing the failed CTA with a new CTA fitted with connectors that will not exhibit the same failure mode. As for how long this will take, it will depend on both how long it will take the connector supplier to determine the cause of the connector failure and manufacture replacements connectors, and on the availability of a suitable repair vessel.
As we understand more, we will post this information to this web site.
Providing electrical power and data connections for new research instruments in the deep-sea. That's the vision behind the Monterey Accelerated Research System (MARS). The system, currently under construction, consists of a 52-km (32-mile) undersea cable that carries data and power to a "science node" 891 meters (2,923 feet) below the surface of Monterey Bay. More than eight different science experiments can be attached to this main hub with eight nodes. Additional experiments can be daisy-chained to each node.
A new way of doing oceanography.
Most oceanographic instruments on the seafloor have no connections with the surface, so they have to run on batteries and store their own data. A cabled observatory like MARS removes those restrictions, allowing scientists to design new types of oceanographic equipment and study the ocean in new ways.
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| The MARS observatory will place advanced science instruments in deep water near the rim of the Monterey undersea canyon. Scientists on land will have constant access to their equipment through a seafloor cable (purple line) that carries both electrical power and data. |
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| The main "science node" of the MARS observatory (shown in orange) has eight "ports," each of which can supply data and power connections for a variety of scientific instruments. Five test experiments are presently planned. Scientists from around the world are encouraged to develop additional experiments for testing on MARS. |
A science and engineering testbed
The MARS undersea observatory testbed will allow scientists and engineers to:
Realizing a dream
The MARS project marks a major step toward realizing a long-held dream in ocean science. Because radio waves barely penetrate water, it is easier to get data from an interplanetary probe than from an instrument in the deep sea. Cabled undersea observatories are beginning to change this, linking seafloor instruments directly to scientists' desktops.
MBARI and its partners installed the MARS cable and main science node in early 2007. The first science instruments will be hooked up to the science node later. For more details on the MARS ocean observatory testbed, see the links at left.
An invitation to researchers
The MARS ocean observatory is intended as a testbed for the use of scientists and engineers who want to design and test instruments that will be used on other ocean observatories. We invite ocean scientists to consider deploying instruments on the MARS ocean observatory testbed. The MARS facilities will allow researchers to develop the tools and protocols necessary to take advantage of a seafloor power supply, real-time, high-bandwidth data transfer, and real-time control of experiments. The MARS system is designed so that tools and protocols developed here will be readily transferable to other cabled observatories as they come on line.
For additional information, contact MARS Operations and Management at marsoandm@mbari.org