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Ocean observation system that involves multiple underwater vehicles and seafloor nodes plays an important role in better learning the ocean, where underwater wireless communication is mandatory for massive data interaction. Optical communication that has wide bandwidth and comprehensive working distance is the preferred method compared to acoustic and other methods. However, the presence of directionality makes the optical method difficult to use especially when the transceiver is equipped on a motive vehicle. In this study, an underwater free-space optical communication method of transmitting information is proposed. Characteristics of underwater optical transmission, as well as the photoelectric signal processing and modulation and demodulation algorithms, are studied and modeled. New approach for realizing underwater free-space optical communication is proposed and simulated. A prototype including a free-space optical transmitter and a receiver is developed; tests in different scenarios were carried out, and the results were observed: (1) by using the minimum number of LEDs, the effect of uniform lighting in space is achieved, and the transmitter coverage reaches 160°. (2) When the power of the transmitter is 10 W and the communication rate is 1 Mbps, the maximum communication distance reaches 13 m.

Pirate vessel tracking satellites to be launched aboard Space X's upcoming historic mission.

NOAA Cautions Boaters to Give Right Whales Space.

China conducts first sea-based space rocket launch.

Meet the SpaceX ships that will never go to space.

NASA's James WEBB Space Telescope successfully arrived in French Guiana Tuesday, after a 16-day journey at sea. The 5,800-mile voyage took WEBB from California through the Panama Canal to Port de Pariacabo on the Kourou River in French Guiana, on the northeastern coast of South America.

The Port of Cherbourg is making 100ha of quay space available to the renewable sector, due to be completed during Q2 2016.

The Port of Cherbourg is making 100ha of quay space available to the renewable sector, due to be completed during Q2 2016.

So many cruise ships, so little space: Sydney Harbour wears out its welcome.

For the first time, scientists, using data from the Copernicus Sentinel-5P satellite, are now able to detect nitrogen dioxide plumes from individual ships from space.

Scientists from the U.S. Naval Research Laboratory Marine Geosciences Division are assisting NASA, the US Army Cold Regions Research and Engineering Laboratory (CRREL) and the European Space Agency (ESA) in developing more accurate monitoring and sustainable forecasting of Arctic sea ice.

A new paper from WCS (Wildlife Conservation Society), in partnership with researchers and practitioners from National Oceanic and Atmospheric Administration, U.S. Coast Guard, Space Quest, Google, and SkyTruth, reviews the use of a maritime vessel communication and navigational safety system that is not only effective in protecting people, but wildlife such as whales, walruses, and other wildlife species as well. With improvements, say the authors, the system will ultimately result in greater engagement by vessel companies and operators in the conservation of marine resources.

A new analysis done to support the investigation into the 2015 sinking of the El Faro cargo ship has calculated the likelihood of a massive rogue wave during Hurricane Joaquin in October of that year - and demonstrated a new technique for evaluating the probability of rogue waves over space and time.

Researchers from the Finnish Geospatial Research Institute and Aalto University will team up with Fleetrange Ltd. and Tallink Grupp as part of a research project carried out under a programme of, and funded by, the European Space Agency (ESA). The goal is to develop techniques for autonomous navigation for ships with focus on safety, using a combination of different sensors, machine learning and artificial intelligence.

Vessel traffic management systems can be employed for environmental management where vessel activity may be of concern. One such location is in San Francisco Bay where a variety of vessel types transit a highly developed urban estuary. We analyzed vessel presence and speed across space and time using vessel data from the Marine Monitor, a vessel tracking system that integrates data from the Automatic Identification System and a marine-radar sensor linked to a high-definition camera. In doing so, we provide data that can inform collision risk to cetaceans who show an increased presence in the Bay and evaluation of the value in incorporating data from multiple sources when observing vessel traffic. We found that ferries traveled the greatest distance of any vessel type. Ferries and other commercial vessels (e.g., cargo and tanker ships and tug boats) traveled consistently in distinct paths while recreational traffic (e.g., motorized recreational craft and sailing vessels) was more dispersed. Large shipping vessels often traveled at speeds greater than 10 kn when transiting the study area, and ferries traveled at speeds greater than 30 kn. We found that distance traveled and speed varied by season for tugs, motorized recreational and sailing vessels. Distance traveled varied across day and night for cargo ships, tugs, and ferries while speed varied between day and night only for ferries. Between weekdays and weekends, distance traveled varied for cargo ships, ferries, and sailing vessels, while speed varied for ferries, motorized recreational craft, and sailing vessels. Radar-detected vessel traffic accounted for 33.9% of the total track distance observed, highlighting the need to include data from multiple vessel tracking systems to fully assess and manage vessel traffic in a densely populated urban estuary.

During winter months, humpback whales (Megaptera novaeangliae) frequent the coastal waters of Virginia near the mouth of the Chesapeake Bay. Located within the Bay is Naval Station Norfolk, the world's largest naval military installation, and the Port of Virginia, the sixth busiest container port in the United States. These large seaports, combined with the presence of recreational boaters, commercial fishing vessels, and sport-fishing boats, result in a constant heavy flow of vessel traffic through the mouth of the Chesapeake Bay and adjacent areas. From December 2015 to February 2017, 35 satellite tags were deployed on humpback whales to gain a better understanding on the occurrence, movements, site-fidelity, and overall behavior of this species within this high-traffic region. The tags transmitted data for an average of 13.7 days (range 2.7-43.8 days). Location data showed that at some point during tag deployment, nearly all whales occurred within, or in close proximity to, the shipping channels located in the study area. Approximately one quarter of all filtered and modeled locations occurred within the shipping channels. Hierarchical state-space modeling results suggest that humpback whales spend considerable time (82.0%) engaged in foraging behavior at or near the mouth of the Chesapeake Bay. Of the 106 humpback whales photo-identified during this research, nine individuals (8.5%) had evidence of propeller strikes. One whale that had previously been tagged and tracked within shipping channels, was found dead on a local beach; a fatality resulting from a vessel strike. The findings from this study demonstrate that a substantial number of humpback whales frequent high-traffic areas near the mouth of the Chesapeake Bay, increasing the likelihood of injurious vessel interactions that can result in mortalities.

Free space optical system could provide alternative to traditional radio frequency system