On January 1, 2019 humans will pass and make the most distant observation of a world in our solar system. On this date just days away the New Horizons will pass Object 2014 MU69 in the Kuiper Belt. See the tweet thread by Alex Parker is fantastic as it illustrates a bit about how this observation has been made possible.

Alex Parker:

In just a few hours I will depart for Maryland for New Horizons' New Years flyby of the Kuiper Belt Object (486958) 2014 MU69. Before I go, I thought I would re-tell some of the stories about how we came to know about this little world. pic.twitter.com/iE7f0KeFVK

More at his article here.