Apollo 13 was the 3rd attempt to land humans on the Moon and the 1st to fail. Fifty-six hours into the mission, an explosion forced the crew to abort their Moon landing and take shelter in the Lunar Module. The crew ultimately returned to Earth safely.
Three years ago, on October 19, 2014, comet C/2013 A1 Siding Spring passed within 138,000 kilometers of Mars. At the 2017 meeting of the Division for Planetary Sciences of the American Astronomical Society, we heard a progress report on Mars orbiter imaging of the comet's nucleus.
The House of Representatives proposed $2.1 billion for NASA's planetary science budget, which would be an all-time high. Part of the increase would be used to start work on a new reconnaissance and communications orbiter.