Livio Tornabene recently completed work that confirmed his discovery of an asteroid impact site near the Panama Canal. It marks the completion of one of the first research studies into planetary geology at USF.
Tornabene’s finding is the culmination of a year’s worth of work and research, which included a trip deep into the rain forest of Panama. The location of the site in such a harsh climate made the research particularly difficult.
“It was located in a triple canopy rain forest and partly under water,” Tornabene, a graduate student at USF seeking a degree in geology, said. “It made it difficult to find rock samples.”
Tornabene works with academic adviser Jeffrey Ryan, a professor in the department of geology who teaches a class in planetary geology. Ryan said he marvels at the challenges this site presents.
“You’re reading it by Braille,” Ryan said of the site. “Worst case tropical forest, and it’s eroded.”
The location of this anomaly has been known since 1972, though no one had been able to identify it as an impact location, Tornabene said. It came to the attention of Ryan when Bob Stewart, a retired Panamanian geologist, brought him samples from the site.
Ryan noticed the makeup of the rocks was unlike what is normally found in that region.
“He brought me an entire cargo container of rocks,” he said. “It was definitely odd.”
The rocks sat idle in Ryan’s office until Tornabene came to him in response to a Web page about his planetary geology class. Though this is not Ryan’s specialty, he gave the samples to Tornabene and agreed to work with him on the project.
“When you have a good, motivated student like Livio, you can learn your way in,” Ryan said.
Last week, Tornabene presented his discovery of the impact site to geologists from across the country at the American Geophysical Union meeting in Boston. The response he got was positive. Tornabene said the discovery will be published within the next year in the Journal of Meteoritics and Planetary Science.
There are still questions, however, to be answered about Tornabene’s impact site. Tornabene said that craters, particularly eroded ones such as this, are difficult to study.
“You have to look at the microscopic features,” Tornabene said. “These things come trucking in at 25,000 miles per hour or more and send out a shock wave and thermal explosion.”
The force of the impact is often hundreds of times stronger than the atomic bomb that was dropped over Hiroshima, Tornabene said. The level of damage coupled with erosion makes it difficult to estimate the size of the asteroid, he said. Tornabene estimates the asteroid to have had a diameter of 2.2 to 3 kilometers, while Ryan thinks it may be substantially larger, between 4 and 5 kilometers.
Tornabene is also currently working on the difficult task of dating the impact. Ryan said dating these impact sites is important in understanding them.
“Asteroids typically come in groups and are possibly related,” Ryan said. “It is a constant learning process, very empirical.”
Studying impact craters on Earth is a difficult process, Ryan said. Unlike moons or other planets in our solar system where craters can be easily seen by a telescope, those on Earth are often quickly covered with vegetation and water and are eroded away, he said.
Ryan said finding impact craters is important so that we can learn more about these impacts, how often they happen, and how they affect earth.
“Knowing the frequency would be very nice,” Ryan said.
As his work continues, Tornabene will soon be heading to the University of Tennessee in Knoxville to work with Harry McSween who is known for his work with rocks from Mars. Tornabene’s goal is to continue his work in planetary geology and to teach. He also hopes to further push planetary geology, which is a relatively new field, into the mainstream of higher learning.
“I’d like to better inform about what started in the beginning and continues today,” Tornabene said. “Teaching is my passion.”
Tornabene said he feels very fortunate that Ryan and the other members of the geology department gave him this opportunity.
“The faculty at USF is very personable,” Tornabene said. “The fact that they allowed me to do this, I can’t thank them enough.”
Ryan said he looks forward to applying Tornabene’s work to his planetary geology class. He said that it is important to show students how science can be applied.
“It’ll be a big part of the course I teach,” Ryan said. “It shows the scientific method in action.”
As for the direction the scientific community at USF is going, Ryan said he is very excited.
“We’ve brought in a lot of new people … There is a lot of energy and a lot of excitement,” he said.
Ryan said he is also very proud of Tornabene for his accomplishment.
“When someone takes off, that’s gratifying,” Ryan said.
“He came in uncertain, and now he knows he can play the game.”