Question

Recently the James Webb space telescope detected six massive ancient galaxies. They are very old and very far away. But these galaxies must still exist today and be even heavier now. Why can't we see any such huge galaxies near us now?

A) These ancient galaxies might have merged with others, forming larger structures that are not individually recognizable now.
B) The expansion of the universe might have caused these ancient galaxies to move far beyond our observable universe.
C) Due to their immense age, these galaxies might have exhausted their gas reservoirs, halting significant star formation, making them less luminous and observable.
D) The light from these ancient galaxies takes so long to reach us that they appear as they did billions of years ago, masking their current state.

Answer 1

There can be several reasons why we don't see huge ancient galaxies near us today, including mergers with other galaxies, the expansion of the universe, depletion of gas reservoirs, and the time it takes for light to reach us.

Step-by-step explanation:

There can be several reasons why we don't see such huge ancient galaxies near us today:

1. The ancient galaxies might have merged with others, forming larger structures that are not individually recognizable now. For example, they could have merged to form galaxy clusters or superclusters.
2. The expansion of the universe might have caused these ancient galaxies to move far beyond our observable universe. The universe is constantly expanding, and this expansion causes galaxies to move apart from each other.
3. Due to their immense age, these galaxies might have exhausted their gas reservoirs, halting significant star formation. As a result, they would be less luminous and observable.
4. The light from these ancient galaxies takes so long to reach us that they appear as they did billions of years ago, masking their current state.