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Here is a general example of the effect known as astronomical parallax.
It plays an important role in connection with solar eclipses and it is here illustrated by a comet that passed near the Earth in 1996.
In March 1996, the Portugal Amateur Association (APAA) as well as EAAE students at high schools in Germany, Sweden, Spain, and Denmark, all equipped with telescopes and CCD cameras, tried to photograph comet Hyakutake. This comet passed about 15 million kilometres from the Earth on March 25.
During the month of March the weather across Europe was generally bad, following the worst ice winter in 12 years. However, on one particular occasion, the sky fortunately cleared, and combined photos, obtained at two sites separated by 3000 km were obtained:
You may see the difference between the two images. To the left we have a bright star, to the right is the image of the comet's nucleus. You can easily see the shift of position of comet, relative to the image of the star.
Watching from two different places, this close-by comet nucleus will NOT be viewed in the same sky position:
This is the well known astronomical effect, referred to as parallax.
A full report about these unique observations by students and amateur astronomers may be obtained from the Soenderborg Amtsgymnasium Homepage. This EAAE student project was awarded a prize and allowed a quite precise estimate of the comet distance.