Elements used for radioactive dating
Earth) and what could happen to Earth in an extreme case, etc.
In nature, all elements have atoms with varying numbers of neutrons in their nucleus.We have an activity in one of the PSI workshops "Exploring the Terrestrial Planets," that deals with this topic.So, you can use the radioactive elements to measure the age of rocks and minerals. Their useful range is from about 1/10 their half-life (the time it takes for half of the radioactive element/isotope-- the parent, to convert into a non-radioactive element/isotope-- the daughter) to 10 times their half-life. You can use this to measure the age of a rock from about 128 million years to more than 10 billion years (the Solar System is 4.56 billion years old).It is impossible to predict when a given atom will decay, but given a large number of similar atoms, the decay rate on average is predictable.This predictable decay is called the half-life of the parent atom, the time it takes for one half of all of the parent atoms to transform into the daughter.So, Carbon-14 can only measure things up to just over 50,000 years old, great for determining when someone built a wood fire, but not good for determining the age of a meteorite. It occurs whenever an atom has an unbalanced number of protons and neutrons in its nucleus.
The number of protons usually determines the element the atom belongs to and it is fixed for any particular element.
By studying other planets, we are learning more about our own planet.
The effects of impacts and how they might affect us here on Earth, global climate change (Venus vs.
This may simply have to do with what the media is talking about.
When there is a scientific discussion about the age of, say a meteorite or the Earth, the media just talks about the large numbers and not about the dating technique (e.g. On the other hand, when the media talk about "more recent events," ages that are more comprehendible, such as when early Man built a fire or even how old a painting is (or some ancient parchment), then we bring up the dating technique in order to better validate the findings.
Once the half life of an isotope and its decay path are known, it is possible to use the radioactive decay for dating the substance (rock) it belongs to, by measuring the amount of parent and daughter contained in the sample.