Titan's Materials Could be Older Than Saturn
While Saturn's largest moon likely formed after the ringed planet, the materials that Titan is made of appear to date back long before Saturn existed.
Experts have determined that the nitrogen that makes up a great deal of Titan's atmosphere likely originated from the same birthplace as the Universe's most ancient comets - from the Oort cloud.
A study detailing this discovery was published in the journal Astrophysical Journal Letters.
According to the study, launched and funded as a collaboration between NASA and the ESA, key information about what makes up Titan is found in the massive, icy moon's atmosphere, allowing researchers to test its nature and determine its origins.
Interestingly, the researchers quickly discovered that the atmosphere of Titan - often thought as similar to what an early Earth's atmosphere must have been like - contains an isotope ratio between nitrogen-14 and nitrogen-15 that should not be possible in anything as young as Saturn and Earth's solar system.
Researchers quickly wondered if the ratio could simply have been altered by reactions within Titan's atmosphere.
However, "when we looked closely at how this ratio could evolve with time, we found that it was impossible for it to change significantly," lead researcher Kathleen Mandt said in a statement. "Titan's atmosphere contains so much nitrogen that no process can significantly modify this tracer even given more than four billion years of solar system history."
Knowing this ratio was no fluke, the researchers then set out to compare it to other celestial bodies, searching for the unique isotope ratio's origins.
Eventually, they were able to trace the ratio back to the Oort cloud - the cold and ancient birthplace of many of the Universe's older comets. The birthplace of Saturn's warmer disk of material is far younger by comparison.
Researchers have previously theorized that one of the many ways the Earth could have received its own nitrogen supply was through the same source as Titan. This latest discovery suggests that this was not the case, and the formation of Earth and Titan's atmosphere, while similar in nature, began quite differently.