If you've been to Lowell Observatory recently, you might have noticed.Percival Lowell has a new hat, or, you might say, his house has a new roof.At any rate, visitors to the observatory campus atop Mars Hill will notice that the tomb where Lowell has been buried since 1923 has a slightly different look these days.The traditional dome-shaped roof, made of squares of stained glass still is visible, but it is under a new frame with heavy plastic panels that allow visitors to still see the original tomb underneath.The new cover for the tomb was put in place late last summer and is designed to protect the tomb from both weather and possible vandalism. The project was undertaken under the direction of William L. Putnam, the observatory's sole trustee and a great-nephew of Percival.Putnam told the Daily Sun he decided on the new cover when it became apparent the stained glass paneling on the tomb's original roof tended to spring leaks and it also seemed to draw people who wanted to see if they could throw a rock and break one of the panels."The frame was largely fashioned offsite," observatory director Robert L. Millis said, "and shipped into Flagstaff. Then, it was lifted onto the tomb by a very large crane."Super Sky Products, Inc., a Wisconsin company, designed and made the frame, Millis said. Once it was in place on the tomb, the director explained, the heavy-duty plastic panels were put in place. The material in the panels is designed not only to resist water and rocks, but also to resist ultra-violet rays of the sun, which otherwise might turn them yellow in time, Millis said. He added the same material has been used to protect the stained glass windows of Flagstaff's historic Federated Church.The tomb, itself, long has been a principal visitor attraction on the campus of the observatory.It was built in1923 on a design approved by Constance Lowell, widow of the observatory's founder and first director. Percival Lowell died Nov. 12, 1916, in his home at the observatory, some eight hours after suffering a massive stroke.After a funeral that drew dignitgaries from all over Arizona, the often controversial astronomer's coffin was placed inside a burial vault which then was placed aboveground on the side of Mars Hill and covered with pine boughs. It remained in that temporary "grave" until 1923 when the tomb was completed.Then, the burial vault was moved into the tomb and placed on an undertaker's "dolly." It stood that way, in public view through the door of the tomb, for almost 50 years until observatory officials decided to protect it from the leaks in the glass roof.In the 1970s, Karl L. Scheele, Flagstaff, designed and built a marble sarcophagus which was placed around the vault.