We can see the past, the key lies in space

Posted on: May 5, 2022
Posted by: Izer Hector
Posted in: science

Earth and Mars were formed from material originating largely from the inner solar system; Only a small percentage arose outside the orbit of Jupiter. Photo: NASA/Moon and Planetary Institute

The universe hides secrets that scientists around the world have not currently been able to decipher. There is a lot of curiosity Although it has already been verified, they continue to impress and motivate specialists to study it.

When we want to observe some stars, it is common to take a telescope and see through it, however, it is important to know Everything we look at in the universe has a time delayThat is, we observe what the star looked like in the past.

by page space place Responsible for publishing the scientific issues of the National Aeronautics and Space Administration (NASA for its acronym in English) The unit of measurement for calculating the distance between an object and another in space is light years. Which is equivalent to the distance light travels in one Earth year, that is, nine billion kilometers.

Light travels at a speed of 300,000 kilometers per second, which is equivalent to 186 thousand miles per second. These quantities give the impression that they are moving very quickly, however, the Sun and the planets are so far away that the light they radiate takes time to reach us.

If observations of a starburst on a cold young star indicate the possibility of coronal rain, a phenomenon observed on our Sun but not yet confirmed on a star of this size. Photo: NASA

The farther away the star is from us, the longer it takes for the light to arrive. That is why everything we see is further in the past. For example, the Sun, our closest star, is located 150 million kilometers (93 million miles) away.

If we do the analysis, we get that The light from the largest star in the solar system takes about 8.3 minutes to reach Earth. This means that we always see the sun as it was about 8.3 minutes ago.

Closest star after the sun It is 4.3 light years away and when we see it today, we actually see it as it was 4.3 years ago. In fact, all the other stars we see in the night sky are further away, thousands of light years away. That is, we can never see the star’s present, only predict it.

An image of Neptune taken in 1989 by NASA’s Voyager 2 mission. Photo: NASA

On the other hand, galaxies consist of groups of millions and billions of stars within them. The Andromeda Galaxy is one of the closest galaxies to planet Earth, it is about 2.5 million light-years away. Every time we look at it, we appreciate how it was 2.5 million years ago in the past.

In 2016, NASA’s Hubble Space Telescope was able to observe the most distant galaxy called GN-z11 located in the constellation of the Great Bear. According to experts, it is 13,400 million light-years away, which means that we observe it as it was before 13.4 billion years in the past to about 400 million years after the great explosion.

This was a very important discovery for science, since it was possible to see a galaxy with the shortest period of time compared to the most accepted theory to date, about the formation of the solar system. This represents a major advance in the study of the universe.