A fireball from a comet fragment streaked through the sky at 160,934 km/h, emitting dazzling white, green, and blue light near midnight.
The fireball illuminated the sky over Spain last weekend. (Video: ABC News)
On May 18, residents across Spain and Portugal had the chance to witness a fireball explode directly overhead, according to Space. Near midnight, the fireball shot across the sky, leaving behind a brilliant trail. Numerous videos widely shared on social media captured scenes of white, green, and blue light from the fireball, making the night sky bright as day.
Rocky meteors frequently pass through Earth’s atmosphere at high altitudes. However, last weekend, the object that appeared in the skies of the two countries was moving at a staggering speed of about 160,934 km/h, more than twice as fast as a typical asteroid. Experts noted that its flight path was quite unusual, indicating that it was a fragment of a comet, an icy celestial body formed in the early solar system. It broke apart at an altitude of 60 km above the Atlantic Ocean, and no debris fell to the ground, according to the European Space Agency.
According to Meg Schwamb, a planetary astronomer at Queen’s University Belfast, it is not uncommon for comets to produce meteor showers. “We have many major meteor showers throughout the year, which occur when Earth passes through a cloud of comet debris”, Schwamb stated. For example, the Perseid meteor shower that takes place every August results from Earth moving through the remnants of Comet Swift-Tuttle. These meteor showers illuminate the sky in a way similar to the object that burned brightly last weekend.
The blue fireball falling over Spain.
The air in front of the object was compressed and heated, causing it to erode, crack, and disintegrate. This destruction process releases light and shockwaves if the object is large enough. Schwamb speculated that the object that generated the fireball over Spain and Portugal was slightly larger than typical meteors seen in meteor showers, making it brighter.
In addition to the dazzling light, the disintegration process of the comet fragment could help experts develop measures to protect Earth from larger asteroids. Researchers are concerned that some celestial bodies may go undetected and explode with dangerous impact above cities. For instance, a 16.8-meter meteor exploded over the city of Chelyabinsk in Russia in 2013, which had gone undetected beforehand. Its airburst was equivalent to nearly 500,000 tons of TNT, causing widespread damage and injuring at least 1,200 people.
However, a new generation of observatories is set to come online in the coming years, including the Vera C. Rubin Observatory in Chile, which could detect millions of previously unknown faint asteroids.
