EARLY astronomers primarily used mathematics; that's why so many "early astronomers" are described as "mathematician and astronomer". Until the invention of the telescope in the early 1600's, there were no astronomical tools beyond the octant.
i really o not understand the significance of the question that is asking
Astronomers use the patterns of lines observed in stellar spectra to sort stars into a spectral class. Because a star’s temperature determines which absorption lines are present in its spectrum, these spectral classes are a measure of its surface temperature. There are seven standard spectral classes.
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The method called "parallax.
I've never heard anybody use the phrase "on the sky" in any context.
The telescope wasn't invented until about 1604, so "early" astronomers had no telescopes.
Since the numbers astronomers use are often very large or very small, they frequently use scientific notation to describe sizes and sentences in the universe.
People like engineers or astronomers.
The ability to use the Scientific skill in an appropriate way.
Astronomers used observational and mathematical skills to discover Neptune. They observed irregularities in the orbit of Uranus and calculated the gravitational influence needed to explain these irregularities, leading them to predict and discover the existence of Neptune.
the scientific method?
To compute very large or very small numbers.
scientific notation
the astronomers use Absolute magnitude
Astronomers use infrared light to map the dust in between stars.
They use the bathroom like anyone else in a house or building. They use the restroom, they are astronomers, not astronauts.
The five skills are touch, hearing, smelling, tasting, and sight.