When you use a telescope to see things over the horizon, what you're actually experiencing is the effect of Earth's curvature and the telescope's ability to magnify and bring distant objects into view.
The curvature of the Earth means that objects that are far away from you become obscured by the horizon. However, when you use a telescope, it allows you to see beyond the limitations of your unaided eyesight. The telescope's optics gather and focus light, increasing the apparent size and brightness of distant objects. This magnification enables you to observe objects that would otherwise be hidden by the Earth's curvature.
In simple terms, the telescope brings the distant object above the horizon by "lifting" it optically, making it visible from your vantage point. It essentially extends your line of sight, allowing you to see objects that are physically below your direct line of sight due to the Earth's curvature.
It's important to note that the amount of Earth's curvature you can overcome with a telescope depends on various factors, including the telescope's magnification power and the height of your viewing location. In some cases, atmospheric conditions, such as refraction, can also play a role in allowing you to see objects beyond the horizon.
However, it's worth mentioning that even with a telescope, there are limitations to how far you can see. Objects that are too distant or obscured by atmospheric conditions, such as haze, pollution, or weather conditions, may still remain out of sight, regardless of the telescope's capabilities.