It is not every day you can announce the discovery of thousands of new mountains on Earth, but that is what a US-European research team has done.
What is more, these peaks are all at least 1.5km high.
The reason they have gone unrecognised until now is because they are at the bottom of the ocean.
Dave Sandwell and colleagues used radar satellites to discern the mountains’ presence under water and report their findings in Science Magazine.
“In the previous radar dataset we could see everything taller than 2km, and there were 5,000 seamounts,” Prof Sandwell told BBC News.
“With our new dataset – and we haven’t fully done the work yet – I’m guessing we can see things that are 1.5km tall.
“That might not sound like a huge improvement but the number of seamounts goes up exponentially with decreasing size.
“So, we may be able to detect another 25,000 on top of the 5,000 already known,” the Scripps Institution of Oceanography researcher explained.
The roughness of the seafloor is important also as it steers currents and promotes mixing - behaviours that are critical to understanding how the oceans transport heat and influence the climate.
Satellite observations are an indirect method that uses satellites fitted with radar altimeters.
These spacecraft can infer the shape of the ocean bottom from the shape of the water surface above.
Because water follows gravity, it is pulled into highs above the mass of tall seamounts, and slumps into depressions over deep trenches.
Most of the maps of the gross outlines of mountains on the seafloor have relied on this approach.
Key advances were made using US Navy and European Space Agency satellites in the 80s and 90s.
Now, Sandwell and his team have gathered new, improved datasets from more recent spacecraft - Jason 1, which was recently taken out of service, and CryoSat, which continues to orbit the Earth today.