ASK ASTRO.

This article from Astronomy features experts answering questions about various cosmic topics. The first question addresses the size of a black hole after two black holes merge, explaining that the resulting black hole has both more mass and a larger diameter. The second question discusses how the diameter of a telescope affects the size of observed objects, stating that a larger diameter does not necessarily make objects look larger, but it does make them brighter and more detailed. The third question explores the concept of the visible universe being larger than its age, explaining that the expansion of the universe allows for this phenomenon. The final question examines whether the asteroid Psyche could be the core of the object that formed the Moon, concluding that it is unlikely due to its orbit in the asteroid belt. [Extracted from the article]