Scientists possess a greater understanding of the surface of the **moon**, situated 240,000 miles away, compared to the depths of Earth’s **oceans**.
Throughout the years, spacecraft equipped with cameras and sensors have successfully mapped the lunar surface. In contrast, charting the ocean floor has proven to be significantly more difficult. The tremendous pressure in the deep sea is capable of damaging most equipment, while the expansive bodies of water absorb light, rendering direct observations nearly unattainable.
Currently, a groundbreaking initiative utilizing data from a **NASA-led** satellite is facilitating progress in this area. The **SWOT** satellite (Surface Water and Ocean Topography), a partnership between NASA and the French space agency **Centre National d’Études Spatiales**, has generated one of the most detailed ocean floor maps ever produced.
>”This satellite represents a monumental advancement in our capability to map the seafloor,” remarked David Sandwell, a geophysicist at Scripps Institution of Oceanography, in a **statement**.
### A New Method for Mapping the Ocean Floor
Launched in December 2022, **SWOT** was initially intended to measure water levels across Earth’s oceans, lakes, and rivers. Nevertheless, scientists have found that its cutting-edge technology can also aid in estimating the dimensions and shapes of underwater formations with extraordinary accuracy.
Grasping the layout of the ocean floor is vital for numerous reasons. These maps aid ships in safe navigation, support engineers in laying underwater communication cables, and enhance studies on deep-sea currents, tides, and **tectonic plate movements**—the massive segments of Earth’s crust that shift over extensive periods.
Historically, scientists have relied on **sonar technology** to map the seafloor, which entails sending sound waves from ships and gauging how they rebound off the ocean bottom. However, this approach is slow, as vessels can only cover limited areas at a time, leaving much of the ocean unmapped.
Due to this slow advancement, researchers may struggle to achieve their objective of completing a **full seabed map by 2030**.
### How SWOT is Transforming Ocean Mapping
Many satellites in **low-Earth orbit** do not possess the required resolution for thorough seafloor mapping. However, the data from SWOT is approximately **twice as detailed** as earlier satellite maps, uncovering previously unseen features. In December 2023, a new **SWOT-based seafloor map** was published in the journal *Science*.
NASA also unveiled an **animation** displaying some of the newly found underwater features, including areas near the coasts of **Mexico, South America, and the Antarctic Peninsula**. The map indicates deep-sea zones in **purple** and elevated underwater areas in **green**.
One of SWOT’s key contributions is its capacity to identify **seamounts**—underwater mountains—smaller than those previously mapped. This could potentially raise the count of recognized seamounts from **44,000 to 100,000**. These formations affect ocean currents and establish nutrient-rich environments that draw marine life.
>”Completing the full ship-based mapping by 2030 is unlikely,” Sandwell stated. “But SWOT will assist us in filling in the gaps.”
### How SWOT Identifies Underwater Features
SWOT functions by measuring minuscule alterations in **water height**. Unlike a flawlessly smooth surface, the ocean is irregular. Underwater mountains and other geological formations create slight gravitational fluctuations, resulting in minor elevations in the water. The instruments on SWOT can identify these fluctuations, allowing researchers to infer what is beneath the surface.
The satellite completes an orbit around Earth every **21 days**, covering **90% of the planet**. In just one year, SWOT has amassed more detailed information than **30 years’ worth** of previous satellite missions. The new map boasts a resolution of approximately **5 miles**, enabling scientists to spot features that were once undetectable.
A significant discovery includes the identification of **abyssal hills**—long ridges produced by gradual tectonic movements. These features are the most prevalent topographical characteristics on Earth, encompassing **70% of the ocean floor**. However, due to their smaller size compared to seamounts, earlier satellites faced difficulties in detecting them.
### The Future of Ocean Exploration
The enhanced maps could pave the way for revolutionary geological discoveries, such as identifying **active underwater volcanoes**, previously unrecognized **fault lines**, and even **lost ancient lands** that were once above sea level.
Astrobiologists are equally intrigued by SWOT’s findings. Many researchers speculate that **life on Earth** may have begun at **mid-ocean ridges**, where tectonic plates diverge and create **hydrothermal vents**—superheated, mineral-rich habitats. SWOT data could assist in locating new underwater hot springs, offering valuable insights into the origins of life on Earth and potentially on other celestial bodies.