Close-up view of comet NEOWISE shows it survived a close encounter with the sun

Comets don’t always survive their sojourns in the Inner Solar System, but a new close-up image suggests Comet NEOWISE – the brightest in decades – held it together.

In about 6,800 years, our descendants, should they still be there, can expect a return visit from comet NEOWISE. This 3-mile-wide comet (5-weightmetre) seems to have survived his recent trip around the Sun, as revealed by a new close-up image taken by the Hubble Space Telescope. Its solid core remains intact, indicating potential to return in thousands of years.

This comet, officially known as C / 2020 F3 (NEOWISE), was first spotted last March, and it turned out to be the brightest comet seen in the northern hemisphere since Hale-Bopp in 1997. NEOWISE was visible to the naked eye from early July to mid-August and do his closest approach to the Sun on July 3, within 27 million miles (43 million km), or just inside the orbit of Mercury. The comet is now accelerating towards the outer solar system at about 37 miles per second (60 km / s).

The solid ice core, or core, can’t actually be seen in the new photo, which was taken on August 8, but the image shows some of the gas and dust pouring out of the comet, forming a cloud which measures approximately 11,000 miles (18,000 km) in diameter. This marks the “first time that Hubble has photographed a comet of this luminosity at such a resolution after this closure of a passage by the Sun”, according to a Hubble Press release.

Comets are best described as gigantic dirty snowballs that formed centuries ago in the outer solar system. When close to the Sun, they enter a temporary active state, resulting in a bright coma and jets bursting from the surface, forming a long comet tail.

Some comets do not survive these encounters, disintegrating due to heat and gravitational pressures. It happened to comet ISON in 2013 and more recently at C / 2019 Y4 ATLAS, which was said to be the brightest comet in decades. Astronomers weren’t sure if the same fate could happen cNEOWISE omits.

To find out, Caltech graduate student Qicheng Zhang, along with his colleagues, captured the new image of comet NEOWISE, revealing no discernsigns of fragmentation.

“Hubble has a much better resolution than what we can get with any other telescope on this comet,” Zhang explained in the Hubble press release. “This resolution is essential to see details very close to the kernel. This allows us to see the changes in the dust right after it is extracted from this nucleus due to solar heat, by sampling the dust as close as possible to the original properties of the comet.

Astronomers will now closely monitor any changes in the comet as it moves away from the Sun, including changes in the color of its dust. Ultimately, scientists want to better understand how solar heating affects the material inside the comet and its chemical composition.