• Question: How many atoms do you think are in the world?

    Asked by Dakota to Jonathan, Kellie, Kevin, Melissa, Stephanie on 28 Apr 2016.
    • Photo: Kevin Baker

      Kevin Baker answered on 28 Apr 2016:

      That is a really tough question! I do not think anyone has tried to quantify it before. I think the numbers go way, way past a trillion because in the human body alone, it is difficult to quantify! The below link gives a rough estimate of the amount, and you can multiply that number by 7 billion people. And that number does not even include all of the animals, plants, rocks, and everything else.


    • Photo: Jonathan Jackson

      Jonathan Jackson answered on 28 Apr 2016:

      I have no idea what the answer to this question is – and I love it. That’s always the very best starting point for science. Let me demonstrate how scientists sometimes think through questions when they don’t know the answer.

      I may not know how many atoms are on earth, but I do know that particle physicists often talk about how many atoms are in the universe. So surely someone must know how many atoms there are on earth, right? It might be worth checking out big physics laboratories to see if they know the answer.

      A quick Google search shows that Fermilab has an answer to this question! Here it is: http://www.fnal.gov/pub/science/inquiring/questions/atoms.html. According to them, there are 10^49 or 10^50 atoms on Earth. So that’s like a 1 followed by 49 or 50 zeroes!

      As you can see, science is always about starting with what you know to answer a question, and then finding a way to ask someone or come up with an experiment to carry you the rest of the way. SCIENCE!

    • Photo: Kellie Jaremko

      Kellie Jaremko answered on 28 Apr 2016:

      Wow that’s a great question. I don’t know the answer to that but yesterday I did find out that there are approximately 8.74 million different species of organisms on Earth. Each species has many individuals, all of which are made of tons of atoms. Then you’d have to add up all the atoms in nonliving objects. I’m not sure anyone has tried to add them all up.

    • Photo: Stephanie Moon

      Stephanie Moon answered on 28 Apr 2016:

      I really like everyone else’s answers on this one! There might even be some change in the number of atoms on average on earth at any point in time- because we lose some of our atmosphere to space and we also gain some atoms from meteors etc, but I bet the number Jonathan found (10^50 atoms on the planet) is big enough that the loss of some of the atmosphere and gaining tiny amounts of space rocks and dust wouldn’t really make a difference compared to the huge number of atoms already here!

    • Photo: Melissa Wilson Sayres

      Melissa Wilson Sayres answered on 30 Apr 2016:

      It’s funny that we can kind of estimate how many atoms there are in the World, but we still don’t have a good estimate of how many species there are!