A 23-year-old Santa Rosa man nearing graduation from UC Davis with an engineering degree was killed over the weekend when he was struck by a car on Interstate 80.

Authorities in Yolo County said it appears Joseph Goodwin, a graduate of Montgomery High School, was attempting to cross the highway on foot when he was hit in a westbound lane at about 1:30 a.m. Sunday.

The collision, which remains under investigation, happened just west of the Mace Boulevard overpass, several blocks east of the main UC Davis campus.

“It was not a hit-and-run,” said Officer Rodney Fitzhugh, a spokesman for California Highway Patrol’s Woodland office. The driver stopped, the weather was clear and dry, and passerbys witnessed the collision, he said.

Although it’s still early in the investigation, the death does not appear to be a suicide, Fitzhugh said.

A toxicology report will be ready in a few weeks, said Yolo County Chief Deputy Coroner Gina Moya.

Childhood friends of Goodwin remembered him this week as an intelligent, kind-hearted and happy individual. His parents declined to comment.

He attended Herbert Slater Middle School and Montgomery High, and studied engineering at Santa Rosa Junior College prior to enrolling at UC Davis in 2016.

Justin Vaughn, 24, and Cynthia Molina, 23, both met Goodwin as students at Slater.

“He was a nice, loving dude,” Vaughn said. “He could cheer you up instantly.”

Goodwin excelled at math and tutored others,Vaughn recalled. He was set to receive a bachelor’s degree in mechanical engineering in a commencement ceremony June 17.

He was a leader for a unit of the UC Davis Formula Racing team, where he worked on manufacturing and designing components of electric racing cars, according to his LinkedIn profile.

“He was one of the smartest kids I’ve ever met,” Molina said. “It’s not fair.”

Staff Writer Chris Smith contributed to this story.