# Does anything travel at speed c in the atmosphere.

• jonathang

#### jonathang

I understand the electromagnetic spectrum travels below speed c in Earth’s atmosphere. Is there any part of the spectrum which remains at speed c, or indeed anything which travels at speed c in the atmosphere?

Thanks

The atmospheric effect on the speed of electromagnetic radiation becomes more and more negligible the higher the energy of the incoming photon. gamma rays will travel very close to c through the atmosphere.

Most portions of the EM spectrum have a phase velocity in excess of c.

Some portions I suspect have a group velocity in excess of c, but are highly absorbing at these wavelengths - so you ultimately cannot trasmit information faster than c.

Claude.

## 1. What is the speed of light in the atmosphere?

The speed of light in a vacuum is approximately 299,792,458 meters per second, or c, which is the fastest speed at which anything can travel. However, the speed of light can be slowed down in different mediums such as air, water, or glass.

## 2. Can anything travel at the speed of light in the atmosphere?

No, nothing can travel at the exact speed of light in the atmosphere. As mentioned before, the speed of light can be slowed down in different mediums, but it can never be reached or exceeded.

## 3. Why can't anything travel faster than the speed of light in the atmosphere?

According to Einstein's theory of relativity, as an object approaches the speed of light, its mass increases and it requires an infinite amount of energy to accelerate it further. This is why it is impossible for anything to travel at the speed of light in the atmosphere.

## 4. Are there any exceptions to the rule that nothing can travel at the speed of light in the atmosphere?

Scientists have discovered particles called neutrinos that can travel very close to the speed of light in a vacuum. However, they still have a tiny amount of mass and therefore cannot truly reach the speed of light in the atmosphere.

## 5. How does the speed of light affect our understanding of the universe?

The constant speed of light plays a crucial role in many scientific theories, including general relativity and the Big Bang theory. It also helps us understand the vast distances in our universe and how time and space are interconnected.