Section 1.1: Hubble's Observations

The first image, taken on April 20, 2020, illustrates the disintegration of Comet Atlas as captured by the Hubble Space Telescope. Image credit: Hubble NASA ESA STSci D Jewitt (UCLA)

The second image, captured on April 23, 2020, shows further fragmentation. Image credit: Hubble NASA ESA STSci D Jewitt (UCLA)

David Jewitt, a professor of planetary science and astronomy at UCLA and a leader of one of the Hubble teams, noted, "The changes in appearance between these two days are so significant that it is challenging to connect the pieces. It's unclear whether this is due to the fragments reflecting sunlight like twinkling lights or if different pieces are visible on different days."

Prior to its breakup, Comet Atlas (officially designated C/2019 Y4 (ATLAS)) was estimated to be around 200 meters (660 feet) in diameter.

Section 1.2: The Significance of Fragmentation

Although the disintegration of the comet is unfortunate, it provides a valuable opportunity for astronomers to study a phenomenon they rarely observe in such detail.

"This is incredibly thrilling — not just because these events are fascinating to observe, but also because they are quite rare. Most comets that break apart are too dim for us to see. Such significant events occur only once or twice a decade," explained Quanzhi Ye, an astronomer at the University of Maryland, College Park.

While the exact cause of the comet's breakup remains uncertain, it is likely that outgassing — the release of gas from the comet as it warmed while approaching the Sun — played a role in the fragmentation. This incident may indicate that such endings are more common among comets than previously thought, and further analysis of Hubble's findings could shed light on how Comet Atlas met its demise.

The comet was first identified by astronomers using the ATLAS (Asteroid Terrestrial-impact Last Alert System) robotic survey in Hawaii. After several months of brightening, it started to fracture, with the initial signs of breakup observed by amateur astronomer Jose de Queiroz on April 11, who captured images of Atlas as it split into three pieces.

The remnants of the disintegrated comet are expected to make their closest approach to Earth on May 23, coming within 116 million kilometers (72 million miles) of our planet. Just a week later, these icy fragments will pass within 40 million kilometers (25 million miles) of the Sun.

Thus, the saga of Comet Atlas comes to a close.

James Maynard is the founder and publisher of The Cosmic Companion. He is a native of New England who now resides in Tucson with his wife, Nicole, and their cat, Max.

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