It’s a new, weird world.
The deep space exploration craft New Horizons has sent back the first detailed images of an ancient world floating more than 4 billion miles from Earth, formally known as 2014 MU69. The clearest glimpse yet of MU69 shows that it’s shaped like a snowman, with two roundish lobes that have been fused together.
It is by far the most distant world a spacecraft — and by extension humanity — has ever explored.
“What this spacecraft and this team accomplished is unprecedented,” Alan Stern, the principal investigator of the New Horizons mission, said from the Johns Hopkins Applied Physics Laboratory on Wednesday.
New Horizons — which previously revealed the majesty of Pluto in 2015 — swooped just 2,200 miles from the surface of MU69, which has been temporarily nicknamed Ultima Thule (the International Association of Astronomers will eventually endow MU69 with its official name).
These images, though, are not of that absolute closest approach. Over the coming days and weeks, New Horizons will continue to transmit back more images that will reveal greater detail, and closer views of the object.
“So stay tuned,” Jeff Moore, the New Horizons geology team lead, said on Wednesday.
MU69 is of profound interest to scientists. This world lies in a far-off group of objects, called the Kuiper Belt, that ring the solar system. Temperatures here approach absolute zero (minus 460 degrees Fahrenheit), which is as cold as it gets. Consequently, scientists suspect that these ancient objects have been preserved in relatively pristine condition since the beginnings of the still-forming solar system, some 4 billion years ago.
Seeing MU69, then, is like peering into the solar system’s past.
Moore believes MU69 is composed of small icy bodies that are about 4.5 billion years old. Over time, these objects likely coalesced, and eventually two of these objects began to spiral close to one another. One day, they touched. Now, they’re stuck together.
Viewing MU69 is like looking at some of the “only remaining building blocks of the solar system” said Moore.
And as the New Horizons team suspected, this world is indeed reddish, and likely made up of different ices that have been subjected to space radiation for billions of years.
“Now we can definitely say that Ultima Thule is red,” said Carly Howett, a New Horizons planetary scientist.
As the New Horizons team still awaits more detailed images of MU69, New Horizons will continue to journey deeper into space.
Perhaps scientists will spot another faint, distant object, and send New Horizons that way. The craft itself, while now 13 years old, won’t hold them back
“The spacecraft is in peak health,” said Stern.