Looks as though the two big space exploration events of 2019 have already happened in the first week…
Jan 1, Ultima Thule flyby. Hopefully we’ll continue to get dribs and drabs of information to sate us in the coming months.
Jan 3, Chang’e 4 far side lunar lander and rover. Again, there’s some data to come.
December (?), Chang’e 5, lunar lander and sample return. The launch date is a bit fuzzy, don’t fall off your chair if it slips to next year. If successful, this will be the first lunar sample return mission for more than 40 years so that could be cool.
Ongoing: OSIRIS-REx will continue to make observations and prepare for sample acquisition of Bennu, with a departure date in 2021. Similarly, Hayabusa will begin its sample acquisition phase this year, departing Ryugu in December 2019, on its way to a landing at Woomera test range next year.
Juno will also continue to make close passes above the Jovian surface, with 6 planned in this year.
Parker Solar probe will have two more perihelions, one in April, the other in September, each of them about 0.15 AU from the Sun’s surface. Late in the year it will have another encounter with Venus, which it will use to lower its perihelion even further. It will have further Venus flybys over the coming years, eventually lowering it to a 0.05 AU perihelion.