The object in question is called 2014 MU69, and it’s thought to be an incredibly old space rock that’s remained relatively unchanged since the Solar System first formed 4.6 billion years ago. But tracking 2014 MU69 has been pretty tough. It’s only about 30 miles wide, and it orbits over 4 billion miles from Earth. … Using the Hubble data, along with precise star positions measured by Europe’s Gaia satellite, the team predicted various times when 2014 MU69 might pass directly in front of a star. … However, the first two times the scientists tried to see the occultation, they didn’t see the object’s shadow. The first attempt was on June 3rd, with two separate teams looking in Argentina and South Africa, and the scientists tried again on July 10th with NASA’s SOFIA airplane — a flying observatory — as it flew over the Pacific Ocean. It wasn’t until this weekend, just before midnight Eastern Time on Sunday, that the mission team finally caught the occultation while huddled around telescopes in Chubut and Santa Cruz, Argentina.
This is why science is amazing. It is not always correct. It has to be updated constantly with new information in order to perform even the most trivially different task (e.g. track a new star or a different space rock). But the cumulative knowledge gained thereby let’s us do incredible things, like predict when an object only about 30 miles wide and more than 4 billion miles away will pass between a particular place on Earth and a star that is light years away correctly enough to put a telescope at that place and watch it happen.