Luxor once again appeared before the camera. A graphic on the side of the pyramid left by an asteroid was applied to the building by Touchstone Pictures, a division of Disney, on June 29, 1998, to promote the film, "Armageddon," which opened July 1, 1998. The asteroid stayed on the east face until July 6th.

- http://www.lvstriphistory.com/luxor.htm

It also shows a picture of the graphic. It seems from comparing the picture above to the one on the page quoted here that the graphic was intended to be most effective from a side view in the distance. At first glance it did look like a real hole in the side of the pyrimid.