Mount Jackson Loses Spot as UK's Tallest Mountain After Satellite Reveals Measurement Error

Geography textbook writers, take note: The British Antarctic Survey (BAS) has just made a major correction to its old data. As Independent reports, satellite imagery reveals that Mount Hope in the British Atlantic Territory is 1236 feet taller than previously believed, unseating Mount Jackson as the UK’s tallest peak.

BAS realized the old height was incorrect after surveying mountains in Britain’s Antarctic territory using satellite technology. Inaccurate measurements pose a threat to planes flying over the mountains, and with the mapping project BAS intended to make the route safer for aircraft.

Prior to the survey, Mount Jackson was thought to be the tallest mountain in the British Atlantic Territory and the greater UK at 10,446 feet, the BBC reports. But after reviewing the new elevation data, BAS found that Mount Hope bests it by just 180 feet. Reaching 10,627 feet at its summit, Mount Hope is officially Britain’s tallest mountain.

Historically, mountains were measured on the ground using basic math equations. By measuring the distance between two points at the base of a mountain and calculating the angle between the top of the mountain and each point, researchers could estimate its height. But this method leaves a lot of room for error, and today surveyors use satellites circling the globe to come up with more precise numbers.

Because they’re both located in Antarctica, neither of the two tallest mountains in the UK is a popular climbing destination. British thrill-seekers usually choose Ben Nevis, the highest mountain in the British Isles, as their bucket-list mountain of choice—but at just 4413 at its highest point, climbing it would be a breeze compared to conquering Mount Hope.