When most of us think about science, we don't often think about something very fundamental to the enterprise: what the goal of it all actually is. Reality is a complicated place, and the only tools we have to guide us in understanding what it is and how it works is the combination of what we can observe, measure, and experiment on.
NASA explains the incredible shot captured by the Hubble Space Telescope of 3I/ATLAS shows a 'teardrop-shaped cocoon of dust' trailing behind the object, suggesting it's a sizable comet.