stellar spectrum

stellar spectrum

[′stel·ər ′spek·trəm]
(astronomy)
The spectrum of a star normally obtained with a slit spectrograph by black-and-white photography; the spectrum of a star in a large majority of cases shows absorption lines superposed on a continuous background.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Seeing a second line is unexpected, but the appearance of the spectrum is so different than a stellar spectrum that I can't help but think of Huggins's exclamation that he knew at first glance that this spectrum proves that at least some nebulae are gaseous.
A stellar spectrum records light emitted by distant stars, and was widely used by late 19th and early 20th century astronomers to study a star's composition.
They emphasized the idea that: "the intensity ofa given absorption line in a stellar spectrum is proportional to the concentration ofatoms in the stellar atmosphere capable of absorbing the line" [45, p.
Likewise PINGS, the VENGA group used the data cubes of their observations to produce 2D maps of the star-formation rate, dust extinction, electron density, stellar population parameters, the kinematics and chemical abundance of both stars and ionized gas, and other physical quantities derived from the fitting of the stellar spectrum and the measurement of nebular emission lines.
These emission features stem from extremely ionized calcium (nine-fold ionized, i.e., CaX), which is the highest ionization stage of a chemical element ever discovered in a photospheric stellar spectrum.
The first person to photograph the dark lines of a stellar spectrum was Henry Draper, who by reputation, as well as in fact, had the best combination of astronomical and photographic equipment in the U.S.
By modeling the relative strength of different absorption features in the integrated stellar spectrum of galaxies or regions within galaxies we can estimate relevant physical properties of the stellar populations that are present (e.g., [31, 32]).
For a given set of parameters (temperature, radius, mass), scientists can calculate the state of each chemical element in the atmosphere, thereby deriving its potential signature in a stellar spectrum. Astronomers can then compare a real spectrum to the modeled one, find the best fit, and then indirectly infer the stellar parameters, including the mass.
While inspecting photographic plates taken with the 8-inch Draper refractor during Harvard's stellar spectrum survey, Fleming saw that this object, previously cataloged as a star, exhibited the characteristic bright lines of a gaseous nebula.
A stellar spectrum is obtained by using a prism or grating to spread the star's light into its component colors, much as cloud droplets disperse sunlight into a rainbow.
Atmospheric gases absorb some of this light at specific wavelengths, adding very weak absorption lines to the stellar spectrum. By comparing stellar spectra taken in and out of transits, astronomers can detect chemicals in the planet's atmosphere.
A stellar spectrum tells us what a star is made of.