In honor of tonight's 'Blue Moon,' astronaut Scott Kelly aboard the International Space Station posted this image and wrote, "TGIF Here's a preview of tonight's rare celestial surprise. #BlueMoon on the rise. #YearInSpace." 'Once in a Blue Moon' typically means rare or absurd. This year, it means tonight! According to modIn honor of tonight's 'Blue Moon, astronaut Scott Kelly aboard the International Space Station posted this image and wrote, "TGIF Here's a preview of tonight's rare celestial surprise. #BlueMoon on the rise. #YearInSpace." 'Once in a Blue Moon' typically means rare or absurd. This year, it means tonight! According to modern folklore, the second full moon in a month is a "Blue Moon." But of course that doesn't necessarily mean it's blue. Step outside at sunset, look east and see what color presents itself. Image Credit: NASA #nasa #iss #spacestation #space #isscrew #NASABeyond #moon #bluemoon #science #TGIF Here's a preview of tonight's rare celestial surprise. #Blu...