From Scientific American:
The new images show a large, bright speck of light—the solid core of Comet 332P (short for 332P/Ikeya-Murakami)—trailed by a parade of smaller bluish-white dots. Over the course of three days, those small dots can be seen falling farther behind the comet’s main body.
Comet 332P is currently about the length of five football fields, but observations going back to 2010 show that its size has been deteriorating for some time. The comet and its debris trail are visible because they are made partly of ices that reflect sunlight. As comets approach the sun and temperatures start to rise, those frozen materials can vaporize, and the comet itself essentially becomes unglued. Currently, Comet 332P has a debris trail stretching about 3,000 miles (4,800 km) behind it, scientists said. [5 Amazing Facts about the Comet-Chasing Rosetta Spacecraft]
The new images of 332P are fascinating for scientists because there aren’t many clear, direct observations of this type of cometary death; the photos make up “one of the sharpest, most detailed observations of a comet breaking apart,” according to a statement from the Space Telescope Science institute (STScI) in Baltimore, which manages Hubble’s science operations.
The images of the comet breaking apart were taken when the space rock was just outside the orbit of Mars, about 150 million miles (240 million km) from the sun, and only 67 million miles (108 million km) from Earth, researchers said.
Comet 332P is estimated to be about 4.5 billion years old, or about the age of Earth and the other bodies in the solar system. Comets originate in the Kuiper Belt, the sphere of rocky, icy objects beyond the orbit of Neptune. At some point, gravitational disturbances pushed Comet 322P much closer to the sun, where the additional heat began to write its destruction. (The comet currently …