By: Archi Parekh
The New Horizons space probe flew past Ultima Thule on January 1, 2019. Although it was an unlikely target, the object reveals information about the formation of the solar system. The New Horizons was used to gather data about Ultima Thule, which is barely visible from Earth and the Hubble Space telescope. Scientists faced many challenges to make this mission a success.
While most people watched the Ball Drop this New Year’s Eve, scientists at the John Hopkins Applied Physics Laboratory observed Ultima Thule with the New Horizons spacecraft. The space probe, launched in 2006, has been traveling past planets as far as Pluto. Most recently, New Horizons transmitted detailed images of the dwarf planet and entered the Kuiper Belt. On New Year’s Day, it completed the anticipated Ultimate Thule flyby.
Wait, What’s Ultima Thule?
The Ultima Thule is a cold classical Kuiper Belt object which has been preserved since the formation of the solar system. It was first observed by the Hubble Space Telescope in 2014. However, its distance from Earth and the dull surface made it impossible to study. Scientists had some interesting information that led them to choose Ultima Thule for the flyby.
Ultima Thule has a nearly circular orbit, which indicates that it has always been its current distance from the Sun. Due to minimal perturbations in its orbit, the conditions of Ultima Thule reflect those of the young solar system. The freezing cold temperatures further preserve elements on the cosmic object. The New Horizons spacecraft provided an up-close look at Ultima Thule. Using the data collected, scientists hoped to gain insight into the formation of the solar system.
What Scientists Found
New Horizons found that Ultima Thule is a contact binary, which means that it has two spheres fused together. As Jeff Moore, the lead of the Geology and Geophysics team for New Horizons, puts it, it looks like “planetary formation frozen in time.” The binary object is about 20-40 miles long, with minimal craters on its surface. One of the biggest questions about Ultima Thule was whether it has moons or rings. The mission revealed that it has neither. Scientists await more data from the space probe.
Getting this information was a huge challenge for APL scientists. Without knowing the location and size of the object, as well as having limited visibility of meteorites and other obstacles in the New Horizons’ path, keeping the space probe safe was a challenge. To make things more difficult, the Ultima Thule is just about as bright as dirt. Thus, angling the cameras to actually capture proper images of Ultima Thule was difficult. Perhaps the greatest challenge was patiently waiting for the data and safety report to arrive. The distance causes the data to take time to reach Earth. Moreover, the New Horizons and the Sun are aligned in such a way that radio waves can’t be transmitted. Data will resume transmission starting January 10. In the meantime, scientists are working on analyzing the current data from the January 1 encounter.
Impact and Next Steps
Although this flyby seems insignificant compared to those past Jupiter and Pluto, the information gathered gives deep insights into the formation of the solar system. New Horizons will continue to reveal more about the origins of our part of the universe as it travels deeper into unexplored space.
1)Bartels, Meghan. “After Ultima Thule Flyby, New Horizons Hits Pause on Data Dump.” Space.com, Space.com, 5 Jan. 2019, www.space.com/42903-new-horizons-ultima-thule-flyby-data-intermission.html.
2)“'Everything about This Flyby Is Tougher': New Horizons Just over 100 Days from Ultima Thule.” The Planetary Society Blog, www.planetary.org/blogs/jason-davis/2018/nh-ut-100days.html.
3)The Johns Hopkins University Applied Physics Laboratory. "All about Ultima: New Horizons flyby target is unlike anything explored in space." ScienceDaily. ScienceDaily, 27 December 2018.