Researchers on a seafloor mapping mission discovered a new seamount near the Johnson Atoll in the Pacific Ocean.

The researchers were working aboard the the R/V Kilo Moana, which is an oceanographic research ship owned by the U.S. Navy and operated by the University of Hawaii, the University of New Hampshire reported. 

The researchers were using multibeam echosounder technology to make a map of the seafloor in the late hours of the night when the giant seamount appeared "out of the blue." The researchers then proceeded to map the entire conical seamount. 

The seamount is yet to be named and is located about 190 miles southeast of the uninhabited Jarvis Island. This region has rarely been explored, so the researchers were not particularly surprised to stumble upon and unexpected geographical figure. 

"These seamounts are very common, but we don't know about them because most of the places that we go out and map have never been mapped before," he says. Only low-resolution satellite data exists for the majority of the Earth's seafloor, and seamounts of this size are  often not picked up in the satellite data but advanced multibeam echosounder missions like this one can discover them. "Satellites just can't see these features and we can," said James Gardner, research professor in the UNH-NOAA Center for Coastal and Ocean Mapping/Joint Hydrographic Center. 

The impacts of the seamount are yet to be determined. It's summit is about 13,100 feet below the surface of the ocean, which is too deep to be a hazard to ships or to be a home for diverse fish populations. 

"It's probably 100 million years old," Gardner said, "and it might have something in it we may be interested in 100 years from now."