- This is what exploration is all about, says Nasa researcher Alan Stern, who is responsible for the project, to Business Insider.
New Horizons will take several hundred photographs of Ultima Thule at the passage in order for the researchers to be able to study its geography and surface.
When the nuclear-powered space probe began its journey in 2006, the mission was to study Pluto, 500 million miles from the earth. Nasa then did not know Ultima Thule's existence. Only in 2014 could the celestial body, located 160 million miles beyond Pluto, be documented via the Hubble telescope.
Early history of the solar system
After exploring Pluto in 2015, New Horizons has continued in the unknown.
- If we knew what to expect, we would never have gone to Ultima Thule. It's an object we've never encountered before, says Alan Stern to Business Insider.
Both Pluto and Ultima Thule are in the so-called Kuiper belt - which consists of millions of frozen objects in orbit around the sun beyond Neptune. It is a cold part on the edge of the solar system.
According to the researchers, the Kuiper Belt hides secrets about the solar system's early history. It is hoped that Ultima Thule will reveal something about how planets such as the Earth were formed.
Nasa describes Ultima Thule as a seed, or a building block, to a planet that has not developed further.
Like a time capsule
Alan Stern is similar to the celestial body at a 4.5 billion-year-old time capsule.
- It's like when someone first opened and went into Pharaoh's tomb and discovered a 1,000-year-old culture. The difference is that this is about exploring the beginning of the solar system, he says to Business Insider.
Nasas Voyager probes have traveled further into space, but a craft has never before visited a celestial body at this distance.
Over the past three weeks, Nasa has made a risk assessment of New Horizon's route and recently announced that everything looks good. The flight starts on New Year's Eve and takes place at a distance of 350 kilometers from Ultima Thule.
The first photographs are to be awaited on January 2.