I know what a baseline is, but what baseline is used in astronomy? y do we need vary the length of baselines we use?
is it the diameter of the earh's orbit?
I really do not get the 2nd part.
In astronomy, the term "baseline" refers to the distance between two points or telescopes used to measure the positions or properties of celestial objects. Astronomers use baselines to perform interferometry, a technique that combines the light received by multiple telescopes to achieve higher resolution and sensitivity.
The length of the baselines used in astronomy can vary, and there are a few reasons for this:
1. Angular Resolution: The resolution of a telescope, or its ability to distinguish fine details, is directly proportional to the length of its baseline. Longer baselines provide better angular resolution, allowing astronomers to see smaller and more intricate features of celestial objects.
2. Interpretation of Measurements: By varying the length of baselines, astronomers can obtain different perspectives of the same celestial object. This allows them to make more accurate observations and measurements, as different baselines capture different types of information. By collecting data from multiple baselines, scientists can build a complete picture of the observed object.
3. Filtering Out Noise: Varying the lengths of baselines helps to filter out noise or unwanted signals. By comparing observations made with different baselines, astronomers can identify and distinguish between true astronomical signals and unwanted noise or interference.
Regarding your question about the diameter of the Earth's orbit, it is not directly related to the baseline used in astronomy. While the diameter of the Earth's orbit around the Sun is a large distance (roughly 186 million miles or 300 million kilometers), it is not typically used as a baseline for astronomical observations. Instead, astronomers use shorter baselines between telescopes on Earth or even baselines involving telescopes in space, such as those in satellite-based missions.
In summary, the varying length of baselines used in astronomy helps to improve the resolution, provide different perspectives, and filter out unwanted signals, allowing astronomers to make more accurate observations and measurements of celestial objects.