Spectrographs are instruments that separate EM radiation (primarily light) into a spectrum of frequencies and record the data. The intensity of radiation at the different frequencies can be used to ascertain information about the source of the radiation or the material through which it is passing.
compositions and temperatures
All of the observational tools needed by astronomers: astrolabes, quadrant, clocks, sextants, octant, spectrographs, polarimeters, telescopes, optical mount, radio telescopes, space telescopes, etc. are products of various technologies.
No, he did not know about it. Helium was discovered in spectrographs of the Sun in 1868 and isolated in 1895. Mendeleev's original table skipped from hydrogen (1) to lithium (3).
Rhenium is commonly used in high-temperature superalloys for aerospace applications, as a catalyst in the production of gasoline, and in the manufacturing of electrical contacts and filaments due to its high melting point and resistance to corrosion.
Spectrographs (assuming that's what you mean) are mostly used in astronomy. By analyzing the spectrum of radiation of a star, astronomers can learn how hot it is, and how much of it is composed of hydrogen, helium or other elements. For example, "red giant" stars are relatively cool enough for molecules to exist. The spectra of molecules have been detected in red giant stars.
spectrographs
they look at it
Astronomers can collect information about the composition, temperature, density, and motion of astronomical objects by using spectrographs. Spectrographs break down light from celestial objects into its component wavelengths, revealing details about the object's physical and chemical properties. This information helps astronomers better understand the nature and behavior of stars, galaxies, and other astronomical phenomena.
compositions and temperatures
Scientists use spectrographs to analyze the light emitted or absorbed by an object. By spreading light into its various wavelengths, spectrographs can reveal the chemical composition, temperature, and motion of celestial objects such as stars, planets, and galaxies. Scientists study these spectra to gain insights into the properties and dynamics of the objects being observed.
All major astronomical telescopes are equipped with spectrographs, including the Hubble and Spitzer Space Telescopes.
Rhenium is an chemical element with atomic number 75. It is frequently used with tungsten because it adds favorable properties. It is also used for filaments in mass spectrographs.
interferometers because charge-coupled devices are only used in optical telescopes
John Stanley Plaskett has written: 'The Ottawa spectrographs' 'The dimensions and structure of the galaxy' 'The 72-inch reflecting telescope' 'The solar union' 'Notes on the spectrum of Nova Aquilae No. 3' 'The sidereal universe' 'A great reflector for Canada' 'Camera objectives for spectrographs' 'Third list of spectroscopic binaries' 'The character of the star image in spectrographic work' 'An interesting double' 'The spectroscopic binary [beta] orionis' 'Slit width and errors of measurement in radial velocity determinations'
All of the observational tools needed by astronomers: astrolabes, quadrant, clocks, sextants, octant, spectrographs, polarimeters, telescopes, optical mount, radio telescopes, space telescopes, etc. are products of various technologies.
The star's chemical composition; the star's rotation; pulsations of the star; planets or other invisible objects moving around the star; how quickly the star is moving towards us or away from us.
E. H. Richardson has written: 'Spectrographs of the Queen Elizabeth II telescope' -- subject(s): Spectrograph, Victoria, B.C., Victoria, B.C. Dominion Astrophysical Observatory 'War, police, and watch dogs'