The Perseids meteor shower is an annual celestial spectacle that illuminates the night sky between 17th to 26th August. This event is much awaited by astronomers and star-gazers alike, due to the bright meteors and fireballs that are easily visible from Earth.
Understanding Meteors
A meteor, often referred to as a shooting star, is essentially a space rock or meteoroid that ventures into the Earth’s atmosphere. The size of meteoroids can vary extensively, ranging from dust grains to small asteroids. More often than not, they are broken pieces of comets, asteroids, planets, and the Moon that have been blasted off.
These space rocks journey towards the Earth at high speed, and upon encountering Earth’s atmosphere, they heat up and burn, creating vibrant fireballs or “shooting stars”. This is due to the air resistance or drag on the rock. As these meteors traverse through the atmosphere, they leave behind a trail of glowing gas enabling us to observe the phenomenon.
Finally, when a meteoroid survives its atmospheric entry and impacts the ground, it is termed as a meteorite.
What is a Meteor Shower?
A meteor shower occurs when Earth comes across multiple meteoroids simultaneously. Much like Earth, comets also orbit the Sun. However, their orbits are usually more lopsided compared to the nearly circular orbits of planets.
As comets approach the Sun, their icy surface starts to boil off, which results in the release of dust and rock particles, or meteoroids. Consequently, this debris scatters along the comet’s path, particularly in the inner solar system that comprises the Mercury, Venus, Earth, and Mars. As Earth orbits the Sun, it occasionally intersects with a comet’s orbit, leading to an encounter with the scattered comet debris.
These showers get their names from the constellation they seem to originate from; for instance, the Orionids Meteor Shower is named so because it seems to arise near the constellation ‘Orion the Hunter’.
The Perseids Meteor Shower
The Perseids Meteor Shower is a yearly event that peaks in mid-August. This shower was first observed over 2,000 years ago and occurs as Earth encounters the cosmic debris left behind by the comet Swift-Tuttle.
The Swift-Tuttle debris cloud spans about 27 km wide. During the peak display, an estimated 160 to 200 meteors streak through Earth’s atmosphere every hour. These pieces of debris travel at roughly 2.14 lakh km per hour, burning up just under 100 km above the Earth’s surface.
The Perseids derive its name from the constellation Perseus. However, due to pollution and monsoon clouds, it becomes challenging to view the Perseids from regions like India.
Comet Swift-Tuttle
Swift-Tuttle was discovered in 1862 by astronomers Lewis Swift and Horace Tuttle. This comet completes a single rotation around the Sun in 133 years.
Last Modified: February 8, 2024