Dinosaur Tracing Technique to be used to track Solar System History

University of Southern Queensland (USQ) researcher Tim Holt is bringing his paleontology wealth of experience into an exciting area of study, that of the secrets of how our Solar system began - in particular, the formation and evolution of the giant planets like Jupiter and Saturn.

Holt, a Ph.D candidate at the USQ is currently researching the taxonomy and dynamics of small Solar system objects using a technique known as Astrocladistics as part of his research. 

Cladistics is used to study objects that have a common ancestor and widely used in paleontology, as it was developed to help where there were incomplete or missing records - such as tracing back lineage of dinosaur or other fossil species. Astrocladistics is using this technique in a space environment.

Holt is bringing this technique to space research as part of his Ph.D project at USQ centering on the study of a group of asteroids near Jupiter. 

“It’s certainly been interesting merging the two branches,” Holt said. “Part of the challenge was getting people to understand how the technique, often used in palaeontology, could benefit space research.”

Holt went on to say, “It also highlights the importance of interdisciplinary work – we need more people from all backgrounds crossing the floor to help tell the story of the Solar system.”

According to Holt, who co-authored the paper and is studying the Astrocladistics of the swarms of asteroids around Jupiter (of which there are about 8700 Trojans) the rate of discovery is increasing as new instrumentation comes online. The use of cladistics will allow for the use of a larger number of characteristics without needing to truncate the dataset due to missing values. 

The Trojans of Jupiter are a group of asteroids that sit in the Lagrange points around Jupiter. A Lagrange point in a point in space where according to NASA, “the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them.” This means that anything that is in them will stay in them and is a point of stability. Jupiter has two Lagragne points, L4 & L5 and this is where the Trojans sit.

Astrophysics Professor Jonti Horner, one of the supervisors of the project, said Trojans were a vital piece of the puzzle when it came to the formation of the Solar system. 

Scientists studying the Trojans believe they were captured early in Solar system history, making them invaluable for research. 

Planned to launch in October this year, the NASA Lucy mission is a probe designed to study the Trojans of Jupiter with the hope of finding clues to how our Solar system was created and perhaps how life on Earth began. 

The mission is named after Lucy, the Australopithecus afarensis fossil found in Ethiopia in 1974 by Donald Johanson. The fossil is one of the most significant and best known of our ancestors and is believed to be around 3.2 million years old. 

NASA believes that Jupiter's Trojans are the remnants of the primordial material that formed the outer planets. These remnants can also be found in the Kuiper Belt, which sits out beyond the orbit of Neptune and is the home of Pluto. The only satellite that has studied the Kuiper belt is New Horizons and it took 10 years for it to get there!

The Lucy probe should reach the L4 Trojan cloud by 2027, a mere 6 years after launch. However the mission itself is due to last 12 years and will visit 7 Trojan asteroids, all named after famous figures from the Trojan war in Greek Mythology. In 2025 Lucy will also visit a main belt asteroid (an asteroid that is in the main belt located between the orbits of Jupiter and Mars) named 52246 donaldjohanson after the American paleoanthropologist.