We know that most meteor showers are caused by comets, which leave behind dust, rocks and ice that, when they come into contact with the Earth’s atmosphere, ignite. In fact, a few weeks ago we were able to enjoy the Perseids, the meteor shower par excellence of the month of August. Nevertheless, geminids are a strange and interesting exception, since they are produced by the passage of an asteroid. Also, there is another effect that makes Phaethon behave more like a comet than an asteid. And it is that it lights up when it approaches the Sun. But What mystery does the asteroid Phaeton keep for this to happen?
The asteroid (3200) Phaethon has been a mystery to astronomers for a long time. This is because it behaves like a comet when it approaches the Sun, since it lights up; but has no ice reserves, which is what normally produces this effect when frozen water evaporates and scatters light. For this reason, what element can produce this has been sought and several researchers have come to a possible conclusion that has been published in the scientific journal Planetary Science Journal.
And what can make Phaethon light up as it approaches the Sun? Researchers have the theory that it is sodium. “Phaethon is a curious object that is activated when approaching the Sun”, comments the astronomer Joseph Masiero, from the California Institute of Technology in Science Alert. “We know it is an asteroid and the source of the Geminids. But it contains little or no ice, so we were intrigued by the possibility of sodium, which is relatively abundant in asteroids, could be the element that will promote this activity“.
Researchers believe there is hardly any ice left on the asteroid Phaethon. Probably because the frozen water that would have evaporated long ago. But they thought sodium could be behind and to see if they were right used computer models to see if this element could still be present.
And it seems that yes, that sodium is behind the asteroid glow. But, also, that the shower of stars of the Geminids takes place. And it is that the element escapes through the cracks and fissures of the asteroid’s crust, so chunks of rocks come off. Therefore, it is these rocks that can be seen burning from Earth in December.
“Our latest finding is that, under the right conditions, sodium may explain the nature of some asteroids active, making the spectrum between asteroids and comets still more complex than we believed so far “, says Masiero.
In short, studying Phaethon has provided us with more information about his composition. And a more than possible explanation of how an asteroid can produce geminids. Next December, when you look up to look at the meteors, remember that not all meteor showers come from comets. Although perhaps the line that differentiates them from the asteroids is a little more blurred than before. But we still have to investigate these celestial objects further.