Our challenge with looking at comets is they look like fuzzy snowballs from a distance. They look even more distorted when looking through the Earth's atmosphere. James Webb, fortunately, is parked far from Earth and has a mirror several times larger than that of the Hubble Space Telescope, opening our eyes to extremely detailed views of comets in our solar system.
James Webb is also equipped with a spectrometer and is sensitive in the wavelength range of 3 to 5 microns. This happens to also be where the emissions from cometary gases show up well -- such as water vapor, carbon dioxide and carbon monoxide. By studying these gases, we will begin to understand what the heart of the comet (the nucleus) looks like.
"We want to know what the comet's nucleus is made out of," Kelley told Discovery News. "From a distance, all we see is this coma, this bright unbound atmosphere. We can't study the nucleus directly."
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