This is not usual. In fact, it never happened before. An asteroid called 6478 Gault changed its colour from red to blue. "It is the first time scientists have observed a colour-shifting asteroid, in real time," the Massachusetts Institute of Technology said in a release recently. The colour change wasn't as dramatic to the naked eye as an octopus or chameleon shifting its colours. Astronomers witnessed the asteroid's activity in the near-infrared spectrum, which isn't visible to the human eye.
MIT postdoc Michael Marsset called the shift "a very big surprise," saying, "We think we have witnessed the asteroid losing its reddish dust to space, and we are seeing the asteroid's underlying, fresh blue layers."
Astronomers first discovered 6478 Gault in 1988 and named the asteroid after planetary geologist Donald Gault. Until recently, the space rock was seen as relatively average, measuring about 2.5 miles wide and orbiting along with millions of other bits of rock and dust within the inner region of the asteroid belt, 214 million miles from the sun.
In January, images from various observatories, including NASA’s Hubble Space Telescope, captured two narrow, comet-like tails trailing the asteroid. Astronomers estimate that the longer tail stretches half a million miles out, while the shorter tail is about a quarter as long. The tails, they concluded, must consist of tens of millions of kilograms of dust, actively ejected by the asteroid, into space. But how? The question reignited interest in Gault, and studies since then have unearthed past instances of similar activity by the asteroid.
“We know of about a million bodies between Mars and Jupiter, and maybe about 20 that are active in the asteroid belt,” Marsset says. “So this is very rare.”
Meanwhile, supermassive asteroid identified as 2169 Taiwan, a carbonaceous space rock, came very close to the Earth on Thursday at around 11 pm. Fortunately, the giant asteroid failed to hit the Earth and we are safe. Asteroids are small, rocky objects that orbit the Sun. The space rocks (asteroids) approach towards the Earth due to the gravitational forces that affect them. Asteroids can bring tsunamis, shock waves and flattening winds that could be catastrophic.
In recent times, many giant asteroids including 2019 OK, 2019 OD, 2015 HM10, 2019 OE, 2019 NN3, 2019 MB4, 2019 MT2, 2006 QV89, 2016 NO56M, RF12 and others approached towards the Earth, fortunately did not hit our planet. It is said that Earth will reach to its end one day and one of the possible reason for this could be an asteroid.
Coming back to asteroid 2169 Taiwan, the space rock was discovered in 1964 by astronomers at the Purple Mountain Observatory near Nanjing, China, was 270 million kilometres away from Earth during its closest approach. According to the Taipei Astronomical Museum, 2169 Taiwan has a diameter of 14 km-19 km and rotation period of 7.252 hours, orbiting the Sun at a distance of 400 million km once every 4.66 years.