Hubble space telescope: The universe’s time machine showing billions-year-old cosmic past
Hubble Space Telescope works like a time machine, capturing ancient light to reveal how the universe looked billions of years ago.
New Delhi (The Uttam Hindu): The Hubble Space Telescope is often called a “time machine of the universe.” By capturing light traveling from distant celestial objects, it allows scientists to look back in time. Since light takes time to reach Earth, the images we see today actually show how those objects appeared years—or even billions of years—ago.
Astronomy can be considered a form of cosmic archaeology. Through light, scientists study the life cycles of celestial bodies and uncover clues about the evolution of the universe. Telescopes like Hubble help us understand our place in the cosmos and how it works. It is not just about taking images—it is about exploring the edge of time.
The Hubble Space Telescope is more than a telescope—it is an observatory, a satellite, and a symbol of scientific achievement. It orbits Earth at an altitude of about 550 km and completes one revolution in approximately 95–96 minutes. Being above Earth’s atmosphere allows it to capture clear and detailed views of space.
The concept of time travel through Hubble is based on light. In astronomy, a Light-year is a unit of distance representing how far light travels in one year—around 9.5 trillion kilometers. Light travels at about 300,000 km per second.
For instance, sunlight takes around 8 minutes to reach Earth, so we see the Sun as it was 8 minutes ago. The nearest star after the Sun, Proxima Centauri, is about 4.2 light-years away, showing how vast the universe truly is.
Hubble has observed extremely distant objects like the GN-z11, whose light took nearly 13.4 billion years to reach Earth. This means we see it as it existed just 400 million years after the Big Bang, when the universe was only about 3% of its current age.
Similarly, the star Earendel, observed by Hubble, is about 12.9 billion light-years away. Studying such distant objects provides valuable insights into the early stages of the universe.
In conclusion, the Hubble Space Telescope is not just a telescope but a powerful tool that helps scientists uncover the history of the universe by observing ancient light.