Locals watched in astonishment as a fireball exploded and hundreds of meteorite fragments rained down on the Tunisian city of Tatahouine on June 27, 1931. Accordingly, the city later became a major filming location for the Star Wars film series. The desert climate and traditional villages were a major inspiration for director George Lucas, who named Luke Skywalker and Darth Vader’s fictional home planet “Tatooine”.
The mysterious 1931 meteorite, a rare type of achondritic (a melting meteorite) known as diogenite, is clearly not part of Skywalker’s home planet. However, it is similarly named after the city of Tatahouine. A recent study has collected important information about the origin of the asteroid and the early history of the Solar System.
Lucas shot several scenes for Star Wars at Tatahouine. These include Episode IV – A New Hope (1977), Star Wars: Episode I – The Phantom Menace (1999), and Star Wars: Episode 2 – Attack of the Clones (2002). Many famous scenes were filmed here, including the “Mos Espa” and “Mos Eisley Cantina” scenes.
Actor Mark Hamill, who plays Luke Skywalker, reminisced about filming in Tunisia and discussed it with Empire Magazine: “If you could get inside your own mind, leave the crew out and look at the horizon, you’d really feel like you’d been transported to another world”.
Composition and origin
Diogenites, named after the Greek philosopher Diogenes, are igneous meteorites (solidified rocks from lava or magma). They formed deep within an asteroid and cooled slowly, resulting in the formation of relatively large crystals.
Tatahouine is no exception; It contains crystals as large as 5 mm with black veins that cut throughout the sample. The black veins are called shock-induced melt veins and are the result of high temperatures and pressures caused by a projectile striking the surface of the asteroid’s main body.
The presence of these veins and the structure of pyroxene grains (minerals containing calcium, magnesium, iron and aluminum) indicate that the sample encountered pressures of up to 25 gigapascals (GPa). To put this into perspective, the pressure at the bottom of the Mariana Trench, the deepest part of our ocean, is only 0.1 GPa. So it’s safe to say that this sample experienced a pretty severe impact.
By evaluating the spectrum of meteorites (light reflected from their surfaces, divided by wavelength) and comparing this to asteroids and planets in our Solar System, diogenites, including Tatahouine, have been suggested to originate from the second largest asteroid in our asteroid belt. It is known as 4 Vesta.
This asteroid holds interesting and exciting information about the early Solar System. 4 Most of the meteors on Vesta are about 4 billion years old. So they offer a window into past events of the early Solar System that we cannot appreciate here on Earth.
violent past
The latest study investigated 18 diogenites, including Tatahouine, all from 4 Vesta. The authors applied “radiometric argon-argon age dating” techniques to determine the ages of the meteorites. This is based on the study of two different isotopes (versions of elements that contain more or fewer particles called neutrons in their nuclei). We know that a particular argon isotope in samples increases at a known rate with age; This helps scientists estimate the age of a sample by comparing the ratio between two different isotopes.
The team also evaluated deformation caused by collisions, called collisional events, using a type of electron microscopy technique called electron backscatter diffraction.
By combining age dating techniques with microscopy technique, the authors were able to map the timing of impact events on 4 Vesta and the early Solar System. The study suggests that 4 Vesta experienced collision events that continued until 3.4 billion years ago, with catastrophic results during this period.
This catastrophic event, likely a collision with another asteroid, resulted in the production of numerous smaller debris pile asteroids known as “vestoids”. Unraveling large-scale impact events like this reveals the hostile nature of the early Solar System.
These smaller bodies have experienced other collisions that have ejected material toward Earth over the past 50 to 60 million years, including the fireball in Tunisia.
In conclusion, this study demonstrates the importance of studying meteorites; Impacts have played an important role in the evolution of asteroids in our Solar System.
Read more: ‘Star Wars’ planet with two suns: A step towards Luke Skywalker’s Tatooine
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Ben Rider-Stokes receives funding from STFC.