A shadow is a dark shape made when light is stopped or blocked by an object or a person. Some objects are opaque such as stone, metal and wood. This means light doesn't travel through them.

"Ending 2024 with a historic approach!" Astroscale posted online. "Our ADRAS-J mission has achieved the closest ever approach ...

But what does that mean? The simple answer is how heavy something is for its size. If something seems very heavy for its size (like a heavy metal object), we say it is more dense. If something seems ...