Meanwhile, Arthur Holmes (1890-1964) was finishing up a geology degree at the Imperial College of Science in London where he developed the technique of dating rocks using the uranium-lead method.
By applying the technique to his oldest rock, Holmes proposed that the Earth was at least 1.6 billion years old.
Likewise, scientists use radiometric dating to determine the ages of moon rocks, obtained by astronauts.
Taken together, these methods give results that suggest an age for our Earth, meteorites, the moon – and by inference our entire solar system – of 4.5 to 4.6 billion years old.
Previously she was an assistant editor at Scholastic's Science World magazine.
Jeanna has an English degree from Salisbury University, a Master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a science journalism degree from New York University.
When asked for your age, it's likely you won't slip (with the exception of a recent birthday mistake).
But for the sprawling sphere we call home, age is a much trickier matter.This work gave rise to a process known as radiometric dating.This technique is based on a comparison between the measured amount of a naturally occurring radioactive element and its decay products, assuming a constant rate of decay – known as a half-life.Also, because Earth formed as part of our sun’s family of planets – our solar system – scientists use radiometric dating to determine the ages of extraterrestrial objects, such as meteorites.These are space rocks that once orbited our sun, but later entered Earth’s atmosphere and struck our world’s surface.From the fragments, scientists calculated the relative abundances of elements that formed as radioactive uranium decayed over billions of years.