“We think the moon is the result of a giant collision sustained by the planet earth in its infant stages,” said Dr. Carey M. Lisse from the Johns Hopkins University’s department of Applied Physics. “The various craters on the moon are due to the numerous collisions it has sustained numerous comets and asteroids throughout its existence. The earth probably sustained similar collisions, but because of its 70% water coverage and the development of life on its surface, we can’t really see them anymore.”
Dr. Lisse was the featured speaker on September 29th for the Friends of the David M. Brown Arlington Planetarium who hosted their first event for the 2013-14 school year. The theme of the weekend was Comets are Coming in anticipation of the coming of the Comet ISON which has recently entered the inner region of our solar system.
The weekend started on Friday night with a viewing of the full-dome show Oasis in Space. On Saturday night, the Friends hosted a viewing of the movie Deep Impact. The weekend concluded on Sunday with a hands on demonstration about comets by Dr. Lisse followed by a showing of the popular program the Magic Tree house.
In front of an audience of younger and older students, and adults, Dr. Lisse made model comets using a mixture of chocolate sauce (a complex of organics), Windex (methanol and ammonia), soil, dry ice (solid carbon dioxide) and water. During his demonstration, Dr. Lisse answered questions about comets and asteroids, and also what they can teach us about the history of the planet earth and how life potentially evolved.
“We study the leftovers from the formation of ours and other solar system; comets and asteroids,” Dr. Lisse said about his research. “Asteroids and comets are the dinosaur bones of our solar system. Meteorites are in fact pieces of asteroids and comets that have come down to us here on earth which is regularly bombarded by objects from outer space. Methods are currently in development which will allow us to take samples from outer space.”
Regarding the new Comet ISON, Dr. Lisse stated, “ISON was actually discovered by a pair of amateur astronomers in Russia. We predict that ISON will be on top of the sun on thanksgiving day, and it will pass close the earth right around Christmas day which will make a holiday comet for all of you, but not for me because I will be somewhere studying it.”
Dr. Lisse also encouraged the younger students at the demonstration to pursue science if they find it exciting. “I went to a public school when I was younger (Thomas Wooten High School in Maryland), and then pursued astronomy and physics in college and graduate school, so if you all are interested in science, we’ll need the next generation to continue and advance these efforts.”
The Friends will host special events at the David M. Brown Arlington Planetarium one weekend every month until the end of the school year. For more information, visit their website. The theme of October’s weekend will be Mission to Mars.