Astronomy Picture of the Day . ... 1.03.2016 . ... Credit Copyright: Alfred Lee Explanation: What's that in the sky? Earlier this month, in the sky high above Hong Kong, China, not just one unusual type of cloud appeared -- but two. ... Higher in the sky, and further in the background, was a colorful iridescent cloud. ... Either type of cloud is unusual to see in Hong Kong, and unfortunately, after only a few minutes, both were gone. ... NASA Web Site Statements, Warnings, and Disclaimers . ...