For Ultima Thule - which wasn't even known when New Horizons departed Earth in 2006 - the endeavour was more hard.
New Horizons, which is the size of a baby grand piano and part of an $800 million mission launched in 2006, was due to collect data for four hours after the flyby.
New Horizons is moving faster than 30,000 miles an hour, meaning that its zip past the unusual object really needed to be pulled off without even the slightest interference. Eastern, then reconvene 10 hours later to watch first signals from the flyby stream onto their screens.More news: Russian president Vladimir Putin plays hockey in Red Square
"The images coming down this week will already reveal the basic geology and structure" of Ultima Thule, Stern said, saying the documentation will begin right away. The spacecraft will not be in contact with Earth during close approach but is programmed to send a signal home on the morning of January 1 to indicate its health and whether it recorded all the expected data.
If New Horizons successfully completes this flyby, the encounter may tell us invaluable information about Kuiper Belt Objects like Ultima Thule. The speakers took delight in showing off the latest picture of Ultima Thule, taken just hundreds of thousands of miles before the 12:33 a.m. close approach. "Think of it. We're a billion miles farther than Pluto". "The exploration at Ultima Thule is a fitting way to honor the brash exploration and boldness that was Apollo", Stern wrote in an opinion piece in The New York Times.
Seven instruments on board will record high-resolution images and gather data about its size and composition.
Ultima Thule - or 2014 MU69, as it is called in astronomical catalogs - is estimated at being somewhere around 30 km wide. Traveling at 31,500 miles per hour (50,700 kph), the spacecraft could easily be knocked out by a rice-size particle. The close encounter comes 3½ years after the spacecraft swung past Pluto.
"I can't promise you success".
"We have a healthy spacecraft". "By tomorrow, we'll know how we did". Further details will be forthcoming in the days ahead, as New Horizons sends back color close-ups.More news: Germany: Drugged Driver Forces Car Onto Airport Tarmac
The risk added to the excitement.
And even the USA government shutdown couldn't stop NASA from celebrating such an extraordinary feat.
It takes Ultima Thule 298 years to orbit the sun.
The object Ultima Thule, the nickname for 2014 MU69, was discovered by Marc Buie of Southwest Research Institute in 2014, in an extraordinary search among millions of stars imaged for the goal with the Hubble Space Telescope. As such, it is "probably the best time capsule we've ever had for understanding the birth of our solar system and the planets in it", Stern said.
By week's end, "Ultima Thule is going to be a completely different world, compared to what we're seeing now", Weaver noted.
Based on images taken during the spacecraft's approach, the Kuiper Belt is approximately 20 by 10 miles shaped similar to a bowling pin andspinning end over end. Another possibility is Ultima could be two objects orbiting each other. "New Horizons is on the hunt to understand these objects, and we invite everyone to ring in the next year with the excitement of exploring the unknown".More news: Patrick McCaw signs two-year offer sheet with Cavaliers
"The Kuiper Belt is just a scientific wonderland", Alan Stern, principal investigator of the New Horizons mission, said on Sunday.