Final answer:
Scientists use the composition and distance from Earth to determine the temperature of a star.
Step-by-step explanation:
Scientists use the composition of a star to determine its temperature. By analyzing the elements present in a star's spectrum, scientists can identify the intensity of specific wavelengths of light and use that information to calculate the star's temperature.
Another method used to determine a star's temperature is the distance from Earth. By measuring a star's parallax (the apparent shift in position when viewed from different locations on Earth's orbit), scientists can estimate its distance, which is then used to calculate its temperature.
Using a thermometer to directly measure the temperature of a star is not possible due to the extreme distances and conditions involved.
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