4 students killed are memorialized in BU ceremonies

“This generation - your generation - is the first fully connected generation the world has ever known,’’ said the commencement speaker, Google executive chairman Eric E. Schmidt. “The fact that we are all connected now is a blessing, not a curse, and we can solve many problems in the world as a result. Not only is it an advantage you have; it’s a responsibility you carry.’’

Amid the celebration, the commencement on the sun-baked artificial turf at Nickerson Field carried grief and the raw memories of four deaths this semester.

BU was shaken when graduate student Kanagala Seshadri Rao was shot to death off campus on April 19. Then, two weeks ago, three BU undergrads studying abroad in New Zealand - Austin Brashears, Daniela Lekhno, and Roch Jauberty - died in a van crash.

In a brief memorial during the commencement, the faces of the four BU students killed this semester appeared on giant video screens, each looking as young and happy in their photograph as any graduate in the stadium.

“This is a time to celebrate today but also a time to reflect back,’’ graduating senior Gregory Marcellin of Everett, 21, who studied health sciences, said in an interview moments before the ceremony began. “We’ve been challenged this year, not only academically but socially. This semester we’ve been on the news a lot, for a lot of bad reasons.’’

Even before the New Zealand crash, the BU student body had been battered by painful events, including two cases of what appeared to be extreme hazing and the accusations of sexual assault against two members of the hockey team. Then, in an April Fool’s Day prank that received national attention, the student newspaper published a satire about frat-house rape.

Sarah Ballister of Lomita, Calif., said she played Quidditch - a sport based on the one in Harry Potter novels - with injured junior Stephen Houseman, who was driving the van that crashed in New Zealand. He faces charges of careless driving after he lost control of the van when it hit a patch of gravel.

Ballister, who graduated magna cum laude with a bachelor of arts in English, said the crash had a bigger impact on her life than the other events that marred the academic year.

“The biggest shock and sadness is the recent crash in New Zealand. They’ll be in all of our thoughts today,’’ she said. “But this is still a joyous occasion.’’

The other incidents “bothered me that it happened, but I think the university dealt with it well,’’ she said. “Those things happen all over the country, it just happens that BU got more press for them this year.’’

Ben Austin of Silver Spring, Md., who graduated magna cum laude with a bachelor of arts in international relations and religion, said he did not know anyone hurt or killed in New Zealand but has seen friends grieve. “People are taking the time during the celebration to remember,’’ he said. “It’s a weird combination, I guess. Joy and pain.’’

His parents, Ken and Lucia Austin, said they have been in Boston since Friday. They’ve made two or three trips a year to Massachusetts every year since their son enrolled, his mother said. “This won’t be the last hard thing they have to go through,’’ she said. Come fall, Austin will begin a master’s degree program at Trinity College in Dublin, where he will study philosophy, intercultural theology, and religious ethics.

Schmidt did not directly address the tragedies in his commencement address. But after extolling the world-changing possibilities of technology and the young people who have mastered it, the Internet generation rock star offered some advice: Turn off your gadgets for at least an hour a day.

“Take your eyes off the screen, and look into the eyes of that person you love,’’ said Schmidt, one of the world’s richest people with an estimated net worth of $6.9 billion. “Life is not lived in the glow of a monitor. . . . Life is about who you love, how you live, it’s about who you travel through the world with.’’

Another guest who received an honorary degree Sunday was Thomas G. Kelley, a retired Massachusetts secretary of veterans’ services, Vietnam veteran, and Medal of Honor recipient who was wounded in a combat explosion. After the ceremony, Kelly said young people tested by the violent death of a friend tend to grow up faster. “It shows the vulnerability of all of us,’’ said Kelly, who has never forgotten his friends killed in the war. He said he hopes BU students never forget about their friends who were lost so suddenly.

The university also awarded honorary degrees to Sandra L. Lynch, chief judge of the United States Court of Appeals for the First Circuit; Norman R. Augustine, retired chairman and chief executive of Lockheed Martin; and actor Leonard S. Nimoy, who has lived long and prospered as pointy-eared Mr. Spock, the half-bred, emotionally suppressed Vulcan in the Star Trek television and movie franchise.

Upon receiving his honorary doctorate, Nimoy, who did not speak at Sunday’s ceremony, spread his fingers and flashed the Vulcan salute with both hands, to enormous applause.

Gal Tziperman Lotan contributed to this report. Mark Arsenault can be reached at marsenault@globe.com and on Twitter @bostonglobemark.