Early in the morning on July 4, NASA scientists like Peter Schultz, a professor of geological sciences at Brown and co-investigator on the Deep Impact mission, were already celebrating.
Their 820-pound impactor struck the Tempel 1 Comet at 1:53 a.m. With the successful impact, the scientists uncovered a wealth of information about the composition of comets like Tempel 1 that will take over two years to analyze.
"You can imagine this like going into the last seconds in the fourth quarter of the Super Bowl, waiting for everyone to line up and the ball to be hiked for a game-winning field goal," Schultz told The Herald. "You wonder whether you hit it through the goal posts and we did."
For Brown's planetary geoscientists, this was just another mission in a long line of successful collaborations with NASA and other top geologists to explore our solar system from a geological perspective, learning more about the history of the earth and the history of the solar system.
"The goal of the Deep Impact mission was to get below the surface of the comet and expose material that has been in deep storage for 4.6 billion years," Schultz said. Hopefully, by analyzing images of the high-velocity impact as well as the volatiles and gasses ejected, Schultz and fellow scientists will obtain clues about the early solar system.
To study the comet at impact, the scientists on Deep Impact designed a flyby equipped with telescopes and spectrometers that obtained a diverse range of information about the surface conditions of the comet.
Comets like Tempel 1 are "a repository of the earliest pieces of the solar system. The volatiles, the early gassy stuff, are key in the understanding of the formation and development of planets, oceans, and our atmosphere," said John Mustard, associate professor of geological sciences.
Studying the interior of a comet gives scientists a unique glimpse into the building blocks to the water-rich planets of our solar system, as the icy molecules and particles have not been modified by the normal geological processes that occur in larger bodies, like heating over time, said Jim Head, professor of geological sciences.
The "dirty football-sized snowballs" that Schultz and his colleagues observed being ejected from the impact with Tempel 1 are literally frozen in time, unlike the constantly recycled material on earth or other dynamic planets that have undergone significant modification since their early histories.
In the next few months and maybe years, Schultz hopes to be able to answer a few fundamental questions about the origin of water on Earth. "Our primary goal was to understand the nature of the comets and how they evolved, and whether the water on earth may have been delivered by comets. We hope to at least find out where we started out before life recycled these materials," he said.
Schultz, who specializes in lab impact experiments, will spend most of his efforts analyzing the composition of the comet through the impact cratering process caused by the 820-pound projectile.
In recent years, Brown geologists have been involved with numerous NASA missions. Brown faculty members are currently involved with the Mars Reconnaissance Orbital, which both Head and Mustard are working on, and the Messenger to Mercury, Professor of Geological Sciences Carle Pieters' efforts to map the Moon's mineral make-up. In addition, Brown faculty members are working on the BOM mission, which measures the properties of asteroids in the asteroid belt.
In the future, Head believes that there are "fantastic opportunities for exploration of the solar system - and Brown students are involved."
