How much can you see when you look into the sky? How far can you see? Without help, the answer is not that much and not that far, no matter how good your vision.
Scientists use telescopes, satellites, and probes to extend their vision to the far reaches of the universe. Telescopes, whether on Earth or in space, use mirrors to make distant objects look nearer and larger. Satellites orbit Earth and collect information. Probes journey to faraway places. Most probes fly by their targets, sending images back to Earth. A few land for a closer look.
