Category Archives: Kuiper Belt

New Horizons Completes a Successful Flyby

Outbound from Ultima Thule

This morning we all gathered at the Johns Hopkins Applied Physics Lab to see the last pre-flyby image of Ultima Thule that got sent down overnight. You can see it here, along with a graphic indicating the rotational axis and probable shape of this little Kuiper Belt Object.

A composite of two images taken by New Horizons’ high-resolution Long-Range Reconnaissance Imager (LORRI), which provides the best indication of Ultima Thule’s size and shape so far. Preliminary measurements of this Kuiper Belt object suggest it is approximately 20 miles long by 10 miles wide (32 kilometers by 16 kilometers). An artist’s impression at right illustrates one possible appearance of Ultima Thule, based on the actual image at left. The direction of Ultima’s spin axis is indicated by the arrows.
Credit: NASA/JHUAPL/SwRI; sketch courtesy of James Tuttle Keane

As I write this, the New Horizons flyby sequences of images are on their way to Earth. We will likely see the best one at the press conference on Wednesday. From there on out, the images and data will get better. There is a short-term delay in transmissions over next weekend. That’s because the spacecraft will be occulted by the Sun. However, the data recorders on New Horizons are full, and after the occultation, it’ll resume sending that information back to Earth for admiration and analysis.

Info from the Outer Solar System

This is the second major flyby in the Kuiper Belt for New Horizons. The first, as everyone remembers, was at Pluto. That’s a much bigger world than Ultima Thule, which is a few dozen kilometers long at most. Yet, size isn’t the big deal here. Or, rather, it is. That’s because little worlds the size of Ultima Thule hold the key to understanding the early objects that made up our solar system. Ultima has some of the most pristine materials known. They are in nearly the same shape as when they were born, at least 4.5 billion years ago.

Looking at these places helps us fill in gaps in our knowledge about the formation of the solar system. And, there’s a lot we don’t know about the primordial materials that existed in the solar nebula that existed before the Sun and planets began to form.

So, studies of Ultima Thule, missions to such places as asteroid Bennu and to comets, are all of a piece: they are aimed at showing us the “birth room pictures” of the solar system. That’s why it’s important to get up-close and personal with these objects. It’s why NASA has devoted time, attention, and money to the study of small bodies in the solar system. We may live on one of the bigger bodies, but we have to understand how it got that way. Where it came from, how it evolved? That’s another thing that Ultima can help us understand.

More to Come

There will be more data and images from Ultima Thule over the next year or so. Pay attention, because it’s like looking at baby pictures of ourselves when we were very young. Tiny Ultima (officially known as 2014 MU69) has a LOT to tell us.

#NewHorizons, #UltimaThule, #UltimaFlyby

Ultima Thule

Dream Destination in the Kuiper Belt

On December 31 of this year, the New Horizons spacecraft is set to fly by the distant object Ultima Thule. This tiny world lies in the Kuiper Belt, and the spacecraft has been en route to it since the July 2015 flyby of the Pluto system. The spacecraft has done another trajectory correction burn to home in on Ultima. Another one due about two weeks before closest approach. Then, on New Year’s Eve, the team and a bunch of its closest friends will be having the mother of all parties to celebrate the flyby, which takes place on 1 January 2019 at 05:33:00 UTC.

What is Ultima Thule?

Ultima Thule
rtist’s impression of NASA’s New Horizons spacecraft encountering 2014 MU69, a Kuiper Belt object that orbits one billion miles (1.6 billion kilometers) beyond Pluto, on Jan. 1, 2019. Credit: NASA/JHUAPL/SwRI/Steve Gribben

Until 2014, nobody knew Ultima Thule existed. But, the New Horizons team knew there had to be some distant worlds their spacecraft could visit after the Pluto flyby. So, they used the Hubble Space Telescope to search for possible worlds along the spacecraft’s trajectory. On June 26, 2014, the telescope spotted one. It was promptly dubbed 2014 MU69 and the team went to work on plotting a path to it. The object was renamed “Ultima Thule” based on a public voting process. It means “beyond the known world,” which is most appropriate for this little place out in the Kuiper Belt.

At the moment, nobody knows exactly all of Ultima’s characteristics. It lies about 6.5 billion kilometers from the Sun. That makes the New Horizons approach one of the most distant flybys ever made. Is it one world, or two? There’s a case to be made either way. If it’s two little worlds traveling together, that would make it a contact binary. If it’s one world, it may have a very odd two-headed potato shape. It’s pretty small, only about 30 km across. What the surface contains, its color and other characteristics will only be known as the spacecraft gets closer to take high-resolution images.

What will Ultima Thule Tell us about the Kuiper Belt?

The Kuiper Belt is the region of space where Ultima Thule orbits. It contains many small worlds, plus larger ones such as Pluto, Eris, and Makemake and a number of other dwarf planets. The appearance and composition of Ultima will tell scientists about cratering events (if it’s cratered). Special instruments will study its chemical makeup, and we’ll see if it has moons or a ring. Ultima Thule, by virtue of the fact that it lies so far out there, could well be made of some of the oldest materials in the solar system. They could tell scientists a LOT about what conditions were like in the early solar system.

Stay Tuned

As the days get closer to flyby, we should all be seeing more news about this mission. You can follow it at the mission website, which contains maps and clocks counting down to the event. It’s another great space exploration achievement from a a team that gave us the most amazing looks at Pluto using a spacecraft the size of a grand piano.