The New Horizons probe has traveled 3.5 billion miles from Earth and is scheduled to arrive at Pluto on July 14, 2015. However, on Saturday, July, 4 2015 to probe encountered a glitch at entered safe mode just 10 days before its planned arrival. Fortunately NASA resolved the issue without it affecting any primary or secondary mission objectives. It takes light 4.5 hours to reach Pluto, so any communications with the probe takes half a work day. Two-way communications take 9 hours! Imagine clicking the start button on your computer at 8 am and at 12:30 pm the computer gets the message that you clicked the start button and runs that script to open the start menu. You won't see the start menu until 5 pm! New Horizons will arrive at Pluto at 7:50 am on July 14, 2015.
Read more here