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Spectral lines are of particular importance in astronomy because each different element has a characteristic line spectrum The star Betelgeuse has a lower surface temperature than the Sun; therefore the peak wavelength ofSpectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium capable of letting light pass through it. Several elements were discovered by spectroscopic means, including helium, thallium, and caesium.Spectral lines are of particular importance in astronomy because: A) each different element has a characteristic line spectrum. Atoms in a thin, hot gas (such as a neon advertising sign), according to Kirchhoff's laws, emit light at:In radio source …specific wavelength (like an optical spectral line), and so its detection requires that a radio telescope be set at precisely that given wavelength. The most important of these spectral lines is the 21-centimetre line emitted by neutral hydrogen atoms. The Dutch astronomer Hendrik C. van de Hulst predicted this line…Spectral lines are of particular importance in astronomy because A. only stars can produce bright spectral lines. B. they are the only light bright enough to be seen at large distances. C. they often tell us about the ingredients of the source producing the light.

Spectral line - Wikipedia

A second quantum effect important to spectral lines, particularly at radio wavelengths where h ⁢ ν ≪ k ⁢ T, is stimulated emission (Section 7.3.1). Fortunately, the fundamental characteristics of radio spectral lines from interstellar atoms and molecules can be derived from fairly simple applications of quantum mechanics and thermodynamics.From spectral lines astronomers can determine not only the element, but the temperature and density of that element in the star. The spectral line also can tell us about any magnetic field of the star. The width of the line can tell us how fast the material is moving. We can learn about winds in stars from this.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.Two very important things we can learn from spectral lines is the chemical composition of objects in space and their motions. Chemical composition. During the first half of the 19th century, scientists such as John Herschel, Fox Talbot, and William Swan studied the spectra of different chemical elements in flames.

Astronomy Flashcards | Quizlet

Spectral lines are of particular importance in astronomy because A) each different element has a characteristic line spectrum. B) they can be observed through a diffraction grating. C) they are the only light bright enough to be seen over long distances. D) only stars produce bright line spectra.Spectral lines are of particular importance in astronomy because: A. each different element has a characteristic line spectrum. B. they can be observed through a diffraction grating. C. they are the only light bright enough to be seen at large distances. D. only stars produce bright line spectra.A spectral line is like a fingerprint that can be used to identify the atoms, elements or molecules present in a star, galaxy or cloud of interstellar gas. If we separate the incoming light from a celestial source using a prism, we will often see a spectrum of colours crossed with discrete lines. [>>>]Appendixes C, D, and E in this handbook list the spectral lines considered by the International Astronomical Union (IAU) to be the ones most important to astronomy (as of 2015) and, if they lie in an allocated band, their protection status is listed. In addition to the value of some molecular lines as diagnostic tools, because molecularIn astronomy, stars of spectral type M (the stars with the coolest temperature) are classified as red stars. Mars is called the Red Planet because of the reddish color

Spectral lines are of particular importance in astronomy because

A. only stars can produce shiny spectral lines.

B. they are the only gentle shiny enough to be noticed at large distances.

C. they ceaselessly let us know about the ingredients of the source producing the sunshine.