Light from a star surrounded by a cloud of gas often shows absorption lines
produced when starlight of a specific energy is absorbed by atoms in the gas cloud.
It was taken into account, that the curve must cross the origin of co-ordinate system because if there is no CO, absorption line
height is equal to 0.
The absorption line
actually appeared some months before the system's brightness started to drop.
Atmospheric gases absorb some of this light at specific wavelengths, adding very weak absorption lines
to the stellar spectrum.
The presence of many clouds at different distances creates a thicket of absorption lines
, called the Lyman alpha forest, within the spectrum of light emitted by the quasar.
The astronomers examined the Lyman-alpha hydrogen absorption line
and found evidence of several components of hydrogen along our line of sight to the star.
When astronomers see those fingerprints in a spectrum from Webb, they can then identify the molecule or family of molecules that created the absorption lines
First discovered in 1922, these absorption lines
(more than 400 of them) are seen any time astronomers look toward dust-reddened stars.
Based on the width of the absorption lines
and the intensity, the total pressure and the CO2 concentration in the package is determined.
While competitive laser-based instruments operate in the near-infrared range, the Delta Ray platform was designed to operate in the mid-infrared range because absorption lines
are about 8,000 times stronger than the NIR.
Characteristic narrow absorption lines
, observed at 380 and 435 nm, are most likely from forbidden spin transitions in ferrous iron.
We have analyzed Fe 11 absorption lines
toward several of the reddened stars included in the FUSE survey of molecular hydrogen abundances in translucent clouds.