Craters are all around us. If you live in Sudbury you are actually living inside the second largest crater we know of in the world (the largest is the Vredefort crater in South Africa). About 1.8 billion years ago an asteroid roughly 10 to 15 km across hit this area and created a crater that was about 200 km wide! Due to erosion and geological activity it is actually quite hard to see the crater today but it’s still here in the form of the Sudbury basin.We also have a second crater nearby – Lake Wahnapitae, which is about 37 million years old. In fact, if it wasn’t for erosion, we would be able to see craters covering the Earth just like the Moon. In the early history of the solar system, large impacts were common on Earth. But even now, we continue to be the target of a large object from time to time.We can do a number of simple experiments to create craters and learn about the physics of crater formation. All you need are a few materials you will most likely find around the house.   Things to look for:How is it the crater affected by the speed, trajectory angle, and the material of the impact object? Does the crater look very different depending on the material the object hits? What does it look like in slow motion? Observe the ejecta (the material from inside the crater that lands around it). How is it distributed? If you have a telescope or binoculars take a look at the Moon at night and compare your craters to the ones on the Moon. Can you see the ejecta around any of them?

As we’re celebrating the International Year of Chemistry, chemists are hard at work. Very recently, it was announced that they’re changing the periodic table for the first time since the mid-twentieth century! In order to understand how and why they’re changing the periodic table we have to understand isotopes.An element is determined by how many protons it has. However the number of neutrons it has can vary, and when an element has a different number of neutrons than its most common form, we call it an isotope. The number of protons and electrons remain the same, but the number of neutrons differs, and therefore the atomic mass differs. Up until now, elements on the periodic table have had their atomic masses listed as an average of all their different isotopes. This new change to the periodic table will see 10 elements’ atomic masses listed as a range, rather than a single number. This is important to analytical chemistry that relies heavily on extremely accurate figures. Not all isotopes are stable. Isotopes that are not stable can undergo two different types of reactions in order to reach a stable state. They can either decay or they can fuse together. In both situations a new atom is formed, and the unstable isotope no longer exists.To better visualize the fission and fusion processes, try the activity below:

The soils in Sudbury are often on the slightly acidic side of the scale. For Sudburians this often means that there is a need to “lime” the soil before planting. But is pH only important for Sudburians?Of course not, pH is critical for everyone. Life is actually dependent on the pH of your blood. Human blood is slightly basic, with values ranging from 7.3 to 7.5. If the pH drops below 7.0 or rises above 7.8, the body dies.In fact, all solutions, including the foods that you eat, the fertilizer for your lawn, and the products that you use to clean your house, have a pH. They can be either acidic, neutral or basic. Not knowing the pH of these solutions can cause harmful reactions. Learn how to measure pH using this simple experiment.

If you are anything like I was when I was younger, you love rock candy! There is some very interesting chemistry involved with making this sweet treat.To make rock candy you have to start with a supersaturated solution. Supersaturated solutions are liquids that contain more dissolved solids than they can normally hold at room temperature.To see a supersaturated solution crystallize at an extremely fast rate, watch the video below.

Have you ever wondered how to build a rocket? Well here are some simple instructions to build your own bottle rocket launcher. It will allow you to launch a 2-litre pop bottle using only air pressure. In the video below I demonstrate Science North’s own bottle rocket launcher. The one I present here is a little less complicated than that, but it will work just as well. The key to a bottle rocket launcher is really how you attach the rocket so that it gets pumped full of air and then released. There are many ways to do it and you can be creative, but you might like the simplicity of our suggestion.Let us know if you decide to take on this project. We’d love to see the results! Record a video, post it online and add your link in the comments below. Happy launching!