DAYTONA BEACH, Fla. -- Fans gathered in a semicircle and held candles while they prayed as a day of mourning melted into a nighttime vigil outside the racetrack where Dale Earnhardt died.

Written on white posterboard were thousands of heartfelt messages for The Intimidator, arguably the greatest auto racer in American history, who was killed when he slammed into the wall on the last lap of the Daytona 500 on Sunday.

One salute spotted Monday, from a couple in Texas, was as straightforward and fitting as they come: "The Master. You Will Be Missed By All."

Now that the seven-time Winston Cup champion is gone at age 49, there's a massive void to fill, and many questions to answer.

The HANS device is designed to prevent the type of injuries that killed Dale Earnhardt. (AP)

Some answers were easy. No matter the circumstances, NASCAR has always felt the show must go on. So there will be no postponement of this weekend's race in Rockingham, N.C., and no immediate decision on whether to retire Earnhardt's famous No. 3 Chevrolet.

Other answers won't come so quickly. Most of those concern safety and how NASCAR will react after watching its pre-eminent driver die of head trauma when his car careened out of control at stock car racing's most famous track.

"We're not going to accelerate, we're not going to slow down," NASCAR president Mike Helton said. "It's a work in progress all the time."

That philosophy is troubling to the people who invented the Head And Neck Support (HANS) device that some believe could have saved the life of Earnhardt, Adam Petty and the other two NASCAR drivers who died of head injuries in the last nine months.

"This is getting absurd," said Ken Adams, manager of the company that makes the HANS device. "A Petty dying last year, Earnhardt dying this year. Those are two of the biggest names in racing history."

Only six NASCAR drivers in the 43-car field Sunday used the HANS device. NASCAR has no rules requiring it, although Helton said NASCAR "recommends drivers try it and work with the developers to perfect it for stock car racing."

Dr. Steve Bohannon, who tried to save Earnhardt's life as the driver sat slumped in the wreckage, said the autopsy performed Monday confirmed what everyone suspected: Earnhardt died on impact. He sustained a skull fracture that ran from the front to the back of his brain.

The autopsy didn't include any test whether a HANS device would have saved Earnhardt. Bohannon said he had doubts how effective the device would have been in this accident.

"Even if you restrain the head and neck in this type of injury with the forces we're talking about -- hitting a concrete barricade at 150, 170 mph -- there's still one more element you have to address," Bohannon said. "All those organs internally still move at time of impact," and that could be fatal, too.

Helton said NASCAR officials impounded the No. 3 car and were holding it in an undisclosed location to analyze the accident.

Earnhardt's body was returned to Huntersville, N.C., on Monday night, although a funeral home official said no arrangements had been made by the family. Dale Earnhardt Jr., who finished second in the Daytona 500, said his family appreciated the outpouring of support.

"We'll get through this," he said. "I'm sure he'd want us to keep going, and that's what we're going to do."

Many fans probably feel the same.

Nationwide, they went on a buying spree, scooping up the few remaining Intimidator souvenirs they could find.

"It's been pretty crazy out there," said Mark Phillips, general manager of a sports merchandise store in Dallas. "His merchandise was the most demanded, bar none, in racing or any motor sport."

That was a tribute not only to Earnhardt the driver, but Earnhardt the businessman. He deftly created a rough-and-tumble image true to NASCAR's old-school Southern roots, then cashed in when stock car racing enjoyed its recent new-age surge in popularity.

"Dale touched so many lives in so many different ways," said Jim Hunter, president of Darlington Raceway. "He had that gruff exterior, but he also had a warm side."

Indeed, there is no way to replace Earnhardt, the Man in Black, who always stole the show as he circled the well-worn racing ovals, collecting trophies, friends and enemies wherever he went.

He was America's quintessential anti-hero -- a mysterious, brooding figure who never backed down from a good, old-fashioned tussle on the track, and walked away looking like a winner even when he had lost.

"I guess I'll go out to the races to watch his son now," said Mark Yarashefski, who has come to Daytona from New York for 15 years to watch The Intimidator ride. "But it's never going to be the same."