Á¦ ¸ñ    ASPdLwjvLT ÀÌ ¸§    Lowell ³¯ Â¥    2018/06/29 Á¶ ȸ    1 Why did you come to ? how long does viagra stay in your system drug test At just 20 kilometres in diameter, S/2004 N 1 is certainly the smallest known moon to orbit Neptune, and is estimated to be 100 times fainter than the faintest star that can be seen with the naked eye. In fact, NASAâ?™s Voyager 2 spacecraft flew by the planet in 1989 and, despite making other discoveries, failed to detect Neptune’s 14th moon.