Yes, you can look into the past. All you have to do is stare at the sky
Business Standard: Our senses are stuck in the past. There’s a flash of lightning, and then seconds pass until we hear the rumble of distant thunder. We hear the past.
We are seeing into the past too.
While sound travels about a kilometre every three seconds, light travels 300,000 kilometres every second. When we see a flash of lighting three kilometres away, we are seeing something that happened a hundredth of a millisecond ago. That’s not exactly the distant past.
But as we look further afield, we can peer further back. We can see seconds, minutes, hours and years into the past with our own eyes. Looking through a telescope, we can look even further into the past.
If you really want to look back in time, you need to look up.
Moon is our nearest celestial neighbour - a world with valleys, mountains and craters.
It’s also about 380,000km away, so it takes 1.3 seconds for light to travel from the Moon to us. We see the Moon not as it is, but as it was 1.3 seconds ago.
The Moon doesn’t change much from instant to instant, but this 1.3-second delay is perceptible when mission control talks to astronauts on the Moon. Radio waves travel at the speed of light, so a message from mission control takes 1.3 seconds to get to the Moon, and even the quickest of replies takes another 1.3 seconds to come back. BS
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