According to scientists, whenever we look up at the sky, we witness events from thousands, even millions of years ago. The light of the stars carries traces of the past.

Time travel has been one of humanity’s greatest dreams pursued for centuries.

This concept, frequently encountered in science fiction films, is made possible with gigantic machines or complex devices. Productions like Back to the Future, Interstellar, and Austin Powers explore time travel in captivating ways. Even BBC’s cult comedy series Blackadder constructs a time machine using nothing more than a fruit squeezer and a piece of wood. However, scientists suggest that time travel is simpler than we think, and we do not need a machine for it. All we need to do is to look up at the sky and the stars.

“WE SEE THE PAST WITH OUR EYES”

According to Dr. Michael Boyle, an astronomer at Cornell University in New York, the light from stars goes through a journey of thousands, even billions of years before reaching our eyes.

“The scale of the universe is so vast that even the fastest thing in the universe, light, spends a long time traveling these distances,” says Dr. Boyle. This means that we are actually witnessing the past states of the stars we see in the sky. Some stars we observe may have already ceased to exist by the time we gaze upon them. LIGHT FROM THOUSANDS OF YEARS AGO REACHES US

For instance, the Deneb star in the northern sky is 2,600 light-years away. So, when we look at that star, we are actually observing its state from the 6th century BCE. This corresponds to the end of the Roman monarchy and the construction of the Hanging Gardens of Babylon. Similarly, the Eta Carinae star system is 7,500 light-years away. This means its light set out when humans were newly discovering agriculture. Moreover, the light from the Andromeda galaxy, the farthest galaxy visible to the naked eye, started its journey 2.5 million years ago. During that time, primitive humans (Homo habilis) were beginning to inhabit the Earth, marking the beginning of the last Ice Age. Physicist Prof. Christopher Baird from West Texas A&M University says, “We cannot know if a star exists right now” due to stars being able to explode as supernovas, vanish into black holes, or deplete their fuel and fade away. Even the farthest star discovered so far, Earendel, is 28 billion light-years away, but its light took 13 billion years to reach us. According to Dr. Boyle, “Such a bright star has most likely already ceased to exist.” Could aliens be watching the dinosaurs? The most intriguing part is this: if a civilization 65 million light-years away possesses a powerful telescope, they could currently be observing the dinosaurs when looking at Earth! Although science has not reached this point yet, theoretically, it might be possible to observe the past through advanced telescopes. Perhaps one day, we will be able to watch genuine images of the past through the stars.