In this episode of Startalk Radio, titled “Things You Thought You Knew – Magnetic Cores & Flipping Poles,” Neil deGrasse Tyson explores the fascinating world of magnetism and its impact on our planet. From the movement of Earth’s magnetic poles to the influence of magnetism in love and everyday life, Tyson delves into the science behind these magnetic phenomena.
Earth possesses a magnetic field with a South Magnetic Pole. This phenomenon fascinated Einstein during his childhood, and it is exemplified by the needle of a compass, which is magnetized North and points towards Earth’s South Pole. Interestingly, the principle of opposites attracting applies not only to magnetism but also to love.
The South magnetic pole does not align with Earth’s geographic pole, and the North magnetic pole is currently moving towards Siberia at a rate of 30-50 miles per year. This movement affects the accuracy of compasses and is bringing the North magnetic pole closer to the North geographic pole than ever before. Understanding these changes in the magnetic poles sheds light on the dynamic nature of our planet.
Earth’s core, composed of molten iron that conducts electricity, generates a magnetic field that torques the North Pole. The core can rotate at a slightly different rate than the planet, leading to the wandering of the magnetic field. Additionally, pulsars, which are neutron stars with steeply angled magnetic fields, emit radio waves as they rotate. These examples highlight the presence of magnetism not only on Earth but also in celestial bodies.
Magnetism has practical applications in our daily lives. For instance, the compass rose on the floor of Grand Central Terminal in New York City’s subway helps orient travelers towards the North. Joel Cherico’s pottery allows individuals to experience the universe through taste. Clocks predominantly go clockwise due to historical reasons, and analog clocks provide a better conceptual understanding of time. Area codes were introduced to accommodate multiple phone numbers, and Michael Jackson’s song “PYT” sparked controversy due to its abbreviation for “Pretty Young Thing,” raising important questions about popular culture and societal norms.
This episode of Startalk Radio explored the captivating world of magnetism, from the Earth’s magnetic field and the movement of its poles to the influence of magnetism in everyday life. Neil deGrasse Tyson encourages listeners to continue learning and exploring the wonders of the universe. Magnetism, both on Earth and beyond, continues to shape our understanding of the world around us.