Final answer:
A telescope is necessary to see Pluto with a brightness of magnitude 14, and larger telescopes, such as the 8 m diameter type, collect much more light than the human eye, enabling the observation of distant and faint objects like Pluto.
Step-by-step explanation:
To observe Pluto, which has a brightness of magnitude 14, a telescope is indeed necessary. A telescope can collect far more light than the human eye, making faint objects like Pluto visible. For instance, a telescope with an 8 m diameter can gather substantially more light compared to the fully dark-adapted human eye with a pupil diameter of around 7 mm, enhancing the ability to observe dim objects like Pluto.
With standard telescopes available to most astronomers, Pluto can be seen, but due to its distance and small size, it presents a challenging target. The Mount Palomar telescope, with its 5.08 m diameter, for example, has the potential to resolve Pluto and its moon Charon, but atmospheric effects and other factors such as telescope optics and light pollution can impact the quality of observation significantly.