If so, it could be possible to observe an absorption line
Measurement selectivity requires that within the wavelengths analysed, the other substances should have no absorption lines
or of negligible amplitudes , , .
27 PHYSICAL REVIEW LETTERS, they present data suggesting that the spacings between absorption lines
for several types of atoms 8 to 12 billion years ago were different than they are today.
Previous studies had found a few examples of quasars whose broad absorption lines
seemed to have disappeared between one observation and the next.
16]O gas, which has many absorption lines
in t his region.
This data can be displayed through absorption lines
and by the relative strength shown, the D/H line can be evaluated.
In the course of observing quasars, astronomers have discovered clouds of hydrogen gas that make their presence known by absorbing some of the quasar's radiation, creating a thicket of absorption lines
For scientists interested in knowing the atmospheres chemical makeup, the laser offers another important benefit: the ability to measure water vapor whose absorption lines
lie next to CO2s absorption lines
In Fleming's classification, an A star displayed only hydrogen absorption lines
in its spectrum, while a B star also displayed prominent Orion lines, named after the absorption lines
found in many stars near the Orion constellation and later discovered to come from the element helium.
Scientists at the VU University of Amsterdam and the Max Planck Institute for Radio Astronomy in Bonn used the 100-metre radio telescope in Effelsberg to measure absorption lines
of the methanol molecule at a number of characteristic frequencies.
A laser tuned to sodium absorption lines
illuminates a patch of sky.