# Professor Navigates On High Seas Without GPS

June 23, 2017

Without GPS, Professor Bob Dugan recently navigated a 36 foot sloop-a sailboat with one mast and fore-and-aft rigging-in a competitive ocean race from Marion, Massachusetts to Bermuda.

For 645 nautical miles, Dugan just used a sextant and the heavens, better known as celestial navigation, to guide the sloop on the six-day voyage.

Using a sextant, according to WGBH, "is a complex and involved process that involves a fair amount of calculating, correcting, referring to tables, knowledge of the heavens and the Earth, as well as a lot of common sense."

Given this was the first time Dugan had used a sextant on a long distant voyage, he did remarkably well. When he turned on the GPS at the end of the race, his celestial plot was off by just 1.5 nautical miles! Moreover, the boat placed second in its class of 13 boats, second in celestial out of 11 boats, and second overall out of 50 boats.

## Problem Solving

Operating on the high seas without GPS obliged Dugan to use the problem solving skills he teaches in computer science classes at Stonehill and he intends to share that lesson with his students when school begins in late August.

## Having Backup

"I want to let students know that the skill of debugging a problem in a program is a form of computational thinking that translates to debugging all kinds of problems in real life. I will stress the importance of not always relying on the computer for your answer. For example, the U.S. Navy has started teaching celestial navigation again because hackers can spoof GPS signals to take ships off course. It's always good to have a backup," he said.

While Dugan was the navigator, he is quick to make it clear that the voyage was a team effort, crediting a crew of six hard working sailors and a well-found boat to do so well in the race.

"The captain, John Ring, picked the crew, outfitted the boat and was my celestial navigation coach. The watch captains Jeff Benagh and Brian Duncan did a fine job of keeping the boat speeding towards Bermuda in all types of wind and waves. And the helmsmen Steve Becker and Trinh Nguyen steered the boat day and night. It was a collective endeavor indeed."