We are actually able to see the far past at this time. How is that possible? Well, the way we see the stars and galaxies far, far away is by seeing the light that is emitted or reflected by them. Wait a minute! Isn't the whole seeing process the same? Yeah, when you think you see people, you actually see the light that is reflected from them. Since they are very close to us and light is as fast as Superman, we perceive that we see them in real time. On the other hand, since the distance of far, far away galaxies is really far, light's superpower unfortunately does not help us see (I mean convince ourselves that we see) them in real time. 300,000 km/sec (186,000 miles/sec) in space is ironically very, very slow when you consider the distance between our home, the Milky Way, and the closest neighbor galaxy Andromeda, which is more than 2.5 million light years away. Exactly! We see Andromeda's 2.5 million-year past. Maybe that poor galaxy even vanished a million years ago, and we don't even know it yet.
Now a challenge question: Can we see what happened in a specific place 250 years ago? Can we even listen to and know exactly how the accent of Queen Elizabeth I sounded? What do you think? Stay tuned, we will discuss this soon!