The bluest asteroid in the solar system baffled scientists for years, but now, its SECRET is out

Asteroid Phaethon is the bluest asteroid in the solar system and it had confused the scientists on Earth for a long time. But finally, the secret is out. Find out below.

Why is Phaethon the bluest asteroid in the solar system? Scientists finally have the answer. (Pixabay)

There are many secrets that these small space rocks known as asteroids can carry within themselves. After years of observation, scientists have revealed a lot of information about them. But one secret has eluded them for a long time. And that belongs to a particular asteroid named Phaethon. This asteroid is considered to be the bluest asteroid known in the entire solar system. This means that the asteroid gives off a blue hue when observed from telescopes on Earth. Usually, scientists have found asteroids to either be of gray color due to the rocks and dust or reddish color which indicates the presence of iron in them. But finally, researchers have been able to uncover this secret.

Phaethon is among a small group of asteroids that showcase blue color in our solar system. Among them, Phaethon is the bluest. First observed in the early 1980s, scientists have spent decades trying to decode the reason behind its unique color. Now, a new study was published in the online journal called Icarus where a group of researchers claim that thermal alteration is responsible for this strange phenomenon.

The Sun is behind the bluest asteroid in the solar system

It turns out that asteroid Phaethon, in its orbital pathway, goes extremely close to the Sun. In fact, it goes closer than any other named asteroid at a distance of 13 million miles from the Sun. For reference, the closest planet Mercury revolves around the Sun at three times the distance compared to the asteroid. As a result of getting so close, the asteroid heats up to 800 degrees Celsius and as a result Phaethon gets stripped of its red chemicals like iron and other red colored organic chemicals due to the heat, claims the study.

"You're essentially un-reddening the surface. Although some red color re-accumulates as Phaethon orbits out beyond Mars, it's lost again as Phaethon approaches the sun. After thousands of revolutions, all that remains are materials that reflect darker, cooler colors,” said Carey Lisse, the lead author of the study in a statement.

To showcase this, the researchers created a model which detailed the chemical composition of the asteroid and then added heat to prove that it is indeed the redder substances which get vaporized. After that, what is left behind is the blue colored compounds, which due to lack of any opposition, shine bright.

“I was a little surprised the idea actually worked. It just seems wild to think that maybe Phaethon looks so blue because it gets so hot that it preferentially produces iron gas versus rock gas, but apparently that isn't so crazy after all,” said Jordan Steckloff, co-author of the study.