Ultima Thule: Nasa waits for signal from probe after historic flyby four billion miles away

A Nasa explorer on a quest to collect clues about the solar system’s creation is believed to have reached the system’s outermost region early on New Year’s Day.

Nasa is awaiting news from the spacecraft which is on a path to pass by the icy Ultima Thule space rock on Tuesday, marking a new record for the furthest object ever explored in the Solar System – roughly 6.5 billion kilometres from the Earth.

During its flyby, the New Horizons spacecraft will pass approximately 3,500 kilometres from the surface of Ultima Thule. It is prepared to take gigabytes of photos and other data during the hours it approaches and departs from its closest point to the 30-kilometre-wide body.

Scientists believe the body is farther away from Earth than any other that has had such a close encounter with a Nasa probe.

The New Horizons probe was slated to reach the “third zone” in the uncharted heart of the Kuiper Belt at 12:33am eastern time.

Scientists will not have confirmation of its successful arrival until the probe communicates its whereabouts via Nasa’s Deep Space Network at 10:28am eastern time, about 10 hours later.

Once it enters the peripheral layer of the belt, containing icy bodies and leftover fragments from the solar system’s creation, the probe will get its first close-up glance of Ultima Thule, a cool mass shaped like a giant peanut, using seven on-board instruments.

According to Nasa, scientists had not discovered Ultima Thule when the probe was launched in 2006, meaning the mission was unique. In 2014, astronomers found Thule using the Hubble Space Telescope and selected it for New Horizon’s extended mission in 2015.

“Anything’s possible out there in this very unknown region,” John Spencer, deputy project scientist for New Horizons, told reporters on Monday at the Johns Hopkins Applied Physics Laboratory in Maryland.

Launched in January 2006, New Horizons embarked on a 4 billion mile journey toward the solar system’s frigid edge to study the dwarf planet Pluto and its five moons. The spacecraft, which is the size of a baby grand piano, flew past Pluto in 2015, providing the first close-up views of the planet.

During the fly-by, the probe found Pluto to be slightly larger than previously thought. In March, it revealed that methane-rich dunes were on the icy dwarf planet’s surface.

After trekking 1 billion miles beyond Pluto into the Kuiper Belt, New Horizons will now seek clues about the formation of the solar system and its planets.

As the probe flies 2,200 miles (3,500 km) above Thule’s surface, scientists hope it will detect the chemical composition of its atmosphere and terrain in what Nasa says will be the closest observation of a body so remote.

“We are straining the capabilities of this spacecraft, and by tomorrow we’ll know how we did,” Alan Stern, New Horizons principal investigator, said during the news conference at the Johns Hopkins Applied Physics Laboratory in Maryland. “There are no second chances for New Horizons.”

There is a great deal scientists can learn from both Ultima and the hundreds of thousands of similar objects scientists deem to be in the solar system.

It is “probably the most primitive object ever encountered by a spacecraft, the best possible relic of the early Solar System”, Hal Weaver, the project scientist on the mission, told the BBC.

While the object is officially known as 2014 MU69, it was nicknamed Ultima Thule, a Latin phrase which means “’beyond the borders of the known world”.

Additional reporting by Reuters