Did you notice anything strange in the sky on the mornings or night of 13th and 14th December? Many of you must have read or might be knowing what it was. But, if you have seen and yet have no idea about it, then, let me tell you, you just witnessed the marvelous Geminids Meteor Shower. Time to know more about it.
The Geminids Shower is unique as it is a meteor shower confirmed to be caused by an asteroid. In general, most meteor showers are caused by comets. Each year, during December the Earth passes through the debris cloud scattered by an asteroid named 3200 Phaethon. The fiery display is caused as the debris are vapourised by the Earth’s atmosphere.
The Geminids shower is noted for producing 120 or more meteors per hour, which travel at around 35 kilometres per second, and are often brightly colored. The colors indicate the main chemical composition of that particular meteors. Orange or yellow indicates sodium, yellow signifies iron, blue-green indicates magnesium, and violet indicates calcium. If the meteor appears red, that’s nitrogen and oxygen atoms in the atmosphere glowing as they are superheated by the space dust slamming into them at high speed.
The 3200 Phaethon Asteroid
3200 Phaethon has a quite different eccentric orbit as compared to that of other asteroids. At its furthest point from the centre of the solar system, 3200 Phaethon enters the asteroid belt between the orbits of Mars and Jupiter, around 360m kilometres from the Sun (for context, Earth is around 150m kilometres from the Sun). At its closest point, it’s 21m kilometers away. The asteroid can bare a temperature up to 750°C.
3200 Phaethon has a diameter of about 5.8 kilometres long. It crosses the orbit of the Earth, so it is classed as a near-Earth object. But it’s unlikely to ever hit the Earth. The next nearest approach is not expected to occur until 2093, at a distance almost eight times further away than the moon. Beyond 2093, it is not yet calculated to be predicted.
The extreme variations in temperature experienced by 3200 Phaethon, together with a very short day of just 3.6 hours and regular close encounters with the Sun causes the asteroid to shed dust and debris at a rate great enough that dust tails have been observed. This and other observations have led some astronomers to describe this object as a comet or a “rock comet”, somewhat blurring the line between asteroids and comets.
What does the Sky has more to offer
- Jan 3-4 2019 – Quadrantids 2019
- 21-22 Apr 2019 – Lyrid Meteor Shower
- 5-6 May 2019 – Eta Aquarid Meteor Shower
- 12-13th Aug 2019 – Perseid Meteor Shower
- 21-22 Oct 2019 – Orionid Meteor Shower1
- 7-18th Nov 2019 – Leonids Meteor Shower
- 13-14th Dec 2019 – Geminids Meteor Shower
- 22-23 Dec 2019 – Ursids Meteor Shower
Hope you don’t miss these amazing beautiful showers.
Akshat Mishra is a Physics Undergraduate at Centre for Excellence in Basic Sciences, Mumbai. He feels the need to explore the depths of the not-so-dark universe while at the same time watch the quanta in action. Electronic Music is what puts him in the thinking zone.