# Is it a true explanation of an aberration of starlight?

• Stargazing
• daggab
In summary, astronomer J. Bradley discovered the phenomenon of stellar aberration in 1727, which is caused by the Earth's movement in its orbit around the sun at a speed of 29.8 km/sec. This causes stars to appear to pass through ellipses on the celestial sphere at an angle of 20.5 degrees. To observe a star from a moving Earth, a telescope must be tilted forward in the direction of Earth's motion in order to compensate for the change in the direction of starlight. This is similar to aiming in front of a moving target in order to hit it.
daggab
In 1727, astronomer J. Bradley discovered the phenomenon of stellar aberration. All stars throughout the year on the celestial sphere pass ellipses with an semimajor axis observed from the Earth at an angle of 20.5. Aberration is caused by the movement of the Earth in its orbit around the sun at a speed of 29.8 km / sec. To watch a star from moving Earth you need to tilt а telescope tube forward motion because as long as the light passes a tube. eyepiece with the Earth will move forward.

Last edited:
daggab said:
To watch a moving earth star

a what ?

where did you quote this text from ?

davenn said:
a what ?

Oh, sorry. It's a misprint.

To watch a star from moving Earth...

The English in that explanation is not very clear, but the basic idea is there-- as the Earth moves in its orbit, it changes the direction from which starlight appears to arrive. So to find a star in Winter that you saw in Summer, you have to point the telescope slightly differently. It's the reverse effect of the reason why you have to aim in front of a moving target in order to hit it.

Dougias

## 1. What is an aberration of starlight?

An aberration of starlight is a phenomenon that occurs when the position of a star appears to shift slightly due to the Earth's motion around the Sun. This effect is caused by the finite speed of light and the relative motion between the observer and the star.

## 2. How is an aberration of starlight measured?

An aberration of starlight is measured by calculating the angle of the observed shift in the star's position. This can be done using the formula for aberration, which takes into account the speed of light, the Earth's velocity, and the angle of observation.

## 3. What causes an aberration of starlight?

An aberration of starlight is caused by the combination of the Earth's orbital motion around the Sun and the finite speed of light. As the Earth moves in its orbit, the direction of its velocity changes, causing a slight shift in the perceived position of the star.

## 4. Is aberration of starlight a constant phenomenon?

Yes, aberration of starlight is a constant phenomenon that occurs every time the Earth orbits around the Sun. However, the amount of aberration can vary depending on the speed and direction of the Earth's motion, and the angle of observation.

## 5. How does aberration of starlight affect our understanding of the universe?

Aberration of starlight is an important factor to consider when making astronomical observations and measurements. It provides evidence for the Earth's motion around the Sun and helps scientists to accurately determine the positions and distances of stars in the night sky. Without taking aberration into account, our understanding of the universe would be incomplete.

• Special and General Relativity
Replies
6
Views
982
• Astronomy and Astrophysics
Replies
14
Views
4K
Replies
2
Views
1K
• Cosmology
Replies
21
Views
3K
• Beyond the Standard Models
Replies
2
Views
2K