The birthday celebration for Bei Bei -- his name is pronounced "Bay Bay" -- could be viewed live thanks to the zoo's "Panda Cam," which broadcasts scenes of the four-year-old and his siblings and parents from their enclosure round-the-clock.
Bei Bei will soon be returned to China, under terms of the agreement that brought him to the US zoo on loan.
Under the loan agreement, the zoo pays
China $500,000 a year to support conservation efforts there, and any panda cubs born at the zoo may stay until age four, according to the Smithsonian website.