article_snippet.sent: Phobos is the larger and inner of the two natural satellites of Mars, the other being Deimos.
article_snippet.sent: Both moons were discovered in 1877.
article_snippet.sent: , how much they would weigh and they travel time.
article_snippet.sent: Our planets come as close to each other as 33.9 million miles (54.6 million km), but can be as distant as 250 million miles (400 million km).