The pool area at the Vdara Hotel is developing a nasty reputation for being the target of what employees there call a "death ray," which can singe the hair off the bodies of guests and melt their plastic shopping bags and cups. The Las Vegas Review-Journal's Joan Whitely reports on the Vdara death ray, which she says is caused by light reflecting just so off of the curved glass facade of the hotel tower. The glass focuses the desert sunlight like a giant magnifying glass onto a 10-by-15 square that sometimes moves over the pool area. Whitely explains:

A spokesman for MGM Resorts International, which owns Vdara, said he prefers the term "hot spot" or "solar convergence" to describe it. He went on to say that designers are already working with resort staff to come up with solutions.

Designers foresaw the issue, and thought they had solved it by installing a high-tech film on the south-facing glass panes, according to Gordon Absher, the MGM spokesman. The film scatters more than 70 percent of reflected rays. But that's not enough, Absher acknowledged, as some pool guests are still uncomfortable.

... Viewed from above, the Vdara tower resembles a crescent. The crescent's southern-facing side is concave. There is no tall building farther south to block the sun's hot afternoon rays, so Vdara receives the full brunt. Its pool lies at the center of this southern-facing wall, on top of a low-rise building that is three stories tall.

A concave reflective surface can act "as a lens," according to Kerry Haglund at the Center for Sustainable Building Research, which is at the University of Minnesota.

Vdara Hotel staff estimate that the death ray can reach to about 160 degrees, the temperature at which they say plastic cups melt. Whitely says that the MGM-owned hotel is working on a solution.