Can a magnet inside a soda bottle detect storms from the Sun? Solar storms cause small shifts in Earth's magnetic field. A sensitive compass can pick up these changes.
You build a magnetometer using a soda bottle filled with sand. A bar magnet hangs from a thread inside the bottle. A small mirror on the magnet reflects a light spot onto a wall. When the magnetic field shifts, the spot moves. A one-centimeter shift equals about a quarter of a degree.
Track the spot's position over days or weeks. During a magnetic storm, the magnet swings several degrees within hours. It then returns to its normal position. Large storms often come with aurora displays. Daytime readings can help predict a nighttime light show.
Hypothesis
The hypothesis is that solar storms can affect the Earth's magnetic field, causing small changes in its direction at the surface.
Invisible but measurable, a magnetic field reveals itself through the things it moves. When solar storms disturb Earth's field, a hanging bar magnet inside a sand-filled soda bottle swings several degrees within hours — then slowly returns to its normal position. A small mirror on the magnet reflects a light spot onto a wall, so even a quarter-degree shift becomes visible across the room.
A stream of charged particles from the Sun can shake Earth's magnetic field — and this project lets you see those shifts for yourself. You build a magnetometer using a soda bottle filled with sand, with a bar magnet hanging from a thread inside. A small mirror on the magnet reflects a light spot onto a wall, so when the field shifts, the spot moves. During a magnetic storm, that magnet swings several degrees within hours, then returns to its normal position.
A magnetometer measures the direction of a magnetic field — and this experiment builds one from a soda bottle, sand, and thread. A bar magnet hangs suspended inside the bottle, with a small mirror attached. When the field shifts, the mirror rotates and moves a reflected light spot across the wall. That small movement is the signal.
Method & Materials
You will create a magnetometer to monitor changes in the Earth's magnetic field for signs of magnetic storms.
You will need a clean 2 liter soda bottle, 2 pounds of sand, 2 feet of sewing thread, a small bar magnet, a 3x5 index card, a 1 inch piece of soda straw, a mirrored dress sequin or small craft mirror, super glue, 2 inch clear packing tape, a meter stick, and an adjustable high intensity lamp with a clear bulb.
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With this project, you can detect magnetic storms and measure the changes in the light spot position to detect magnetic storm events. You can even determine the direction of a car's motion by seeing if the spot initially moves east or west!
Why do this project?
This project is interesting and unique because it allows students to monitor changes in the magnetic field that occur inside the classroom. It is also a great way to learn about the effects of solar storms on the Earth's magnetic field.
Also Consider
Experiment variations to consider include measuring the magnetic activity from day to day by measuring the distance between the reference spot and the current spot, and measuring the magnetic activity from different geographic locations.
Full project details
Additional information and source material for this project are available below.
