Science Notes

Famous Scientists

Robert Millikan
Geophysics

EarthScope

Natural Nuclear Reactors

Predicting Earthquakes
Medicine

Great Apes May Be Wiped out by Ebola Virus

Robert Millikan
The following are some excerpts from Jed Graham's article about the American Nobel prize winning physicist Robert Millikan (1868-1953), who won the 1923 Nobel prize in physics for his research on the elementary charge and the photoelectric effect:

"Millikan hadn't even set out to be a physicist. His Greek professor at Oberlin had asked Millikan to serve as a student teacher in physics, figuring that if Millikan could comprehend Greek, he could understand physics."

"After his Greek professor's request, 'I at once purchased an Avery's Elements of Physics and spent the greater part of my summer vacation of 1889 trying to master the subject,' Millikan wrote in The Autobiography of Robert A. Millikan. 'Before fall came, I had worked every problem in the book, and it was these problems that gave me my real understanding and love of the subject of physics.'"

"After graduating and while continuing his teaching at the college, 'I worked through by myself the whole of Sylvanus P. Thomson's ponderous and at that time new book, Dynamo Electric Machinery and was permitted to offer this in satisfaction of the requirement for the master's degree.'"

"Millikan's passion for physics persisted. He worked relentlessly to solve whatever problem he was tackling, 'spending every hour I could steal.'"

"During his first dozen years at the University of Chicago, he split his regular 12-hour days in two - half for teaching and writing textbooks and half working on his own research."

"He kept an open mind. If he discovered his theory was wrong, he'd accept it and go where his research led him."

Graham, Jed 2000, "Scientist Robert Millikan," Investors Business Daily, 19 June 2000.

EarthScope
Greg van der Vink is the project director of EarthScope, the goal of which is to measure the movement and deformation of the Earth below the contiguous US and Alaska. The first phase of EarthScope began in 2003. Its instruments will be completed in 2008 and include the San Andreas Fault Observatory at Depth (SAFOD), which will observe the inner workings of one section of the San Andreas Fault; the Plate Boundary Observatory (PBO), which will monitor the western US and Alaska; and USArray, a network of instruments designed to monitor movement throughout the contiguous US and Alaska.

West, Krista 2005, "Scoping out the Planet," Scientific American, November 2005, 40.

Natural Nuclear Reactors
Alex Meshik describes uranium deposits, in the western African nation of Gabon, which functioned as natural nuclear reactors about two billion years ago. There are three isotopes of natural uranium: uranium 238, the most abundant; uranium 234, the least abundant; and uranium 235 (U-235), the isotope that can sustain a nuclear chain reaction. In 1972, a worker at a French nuclear fuel processing plant noticed that the abundance of U-235, in some uranium samples obtained from the Oklo uranium deposit in Gabon, was slightly less than the expected abundance. In 1953, George W. Wetherill of the University of California at Los Angeles and Mark G. Inghram of the University of Chicago reported that some uranium deposits may have operated as nuclear fission reactors. It was eventually concluded that there were sixteen separate areas within the Oklo and adjacent Okelobondo uranium mines that served as natural fission reactors about two billion years ago. Today, not even the most massive and concentrated uranium deposits can become a nuclear reactor because the concentration of U-235 is too low.

Meshik, Alex P. 2005, "The Workings of an Ancient Nuclear Reactor," Scientific American, November 2005, 82.

Predicting Earthquakes
Electromagnetic signals, at visible, infrared, and radio frequencies, can be used to signal impending earthquakes. By 2015, the technology should exist to implement warning systems for areas like California, China, Japan, Russia, and Taiwan.

Bleier, T., and Freund, F. 2005, "Earthquake Alarm," IEEE Spectrum, December 2005, 22.

Tata, Padma 2005, "Can Earth's Seismic Radio Help Predict Quakes?" New Scientist, 19 November 2005, 28.

Great Apes May Be Wiped out by Ebola Virus
The Ebola virus is working its way through the world's densest population of great apes, in Odzala National Park in the Republic of the Congo. The virus has been spreading at 50 km per year along a path from Yambuku, Democratic Republic of the Congo, where Ebola was first reported in 1976. The Ebola virus is named after the Ebola River in the Democratic Republic of the Congo, formerly known as Zaire, where the virus was first discovered.

Mackenzie, Debora 2005, "Great Apes Face Ebola Oblivion," New Scientist, 5 November 2005, 8.