If the universe is only 14 billion years old, how can it be 92 billion light years wide?
Fermilab・8 minutes read
The universe is expanding, with the visible universe estimated to have a radius of 46 billion light years and constantly losing sight of stars and galaxies due to this expansion. To explore other galaxies, action needs to be taken promptly before objects beyond 15 billion light years become only visible as they were in the past.
Insights
- The universe is expanding due to dark energy, causing the visible universe to have a radius of 46 billion light years, not the previously assumed 13.7 billion light years.
- Stars and galaxies beyond 15 billion light years can only be seen as they were in the past, highlighting the continuous loss of visibility of celestial objects due to the universe's expansion.
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Recent questions
How far is the Sun from Earth?
About 93 million miles away.
How old is the universe?
13.7 billion years old.
What is the estimated radius of the visible universe?
46 billion light years.
What drives the expansion of the universe?
Dark energy.
How many stars disappear from our view every second?
Approximately 20,000 stars.
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Summary
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"Universe's Vastness and Constant Expansion Revealed"
- The Sun is about 93 million miles away from Earth, and it takes light approximately 8 minutes to reach us.
- Astronomers have determined that the universe is 13.7 billion years old.
- The visible universe is estimated to have a radius of 46 billion light years, not 13.7 billion light years as previously assumed.
- The expansion of the universe, driven by dark energy, has caused the sphere from which the Cosmic Microwave Background radiation was emitted to grow from 42 million light years to 46 billion light years.
- Objects that are currently within 15 billion light years can be seen as they are now, but objects beyond that distance will only be visible as they were in the past.
- Due to the expansion of space, we are constantly losing sight of stars and galaxies, with approximately 20,000 stars disappearing from our view every second.
- To explore other galaxies, action needs to be taken promptly due to the ongoing expansion of the universe.
