Astronomers have now observed the radio emission from the neutral hydrogen gas (HI) in a nearby galaxy. Hydrogen gas emits radio emission in a spectral line at a very specific frequency of 1420 MHz.

Supernovae are classified primarily based on their spectral characteristics, notably the presence or absence of hydrogen lines, leading to type I (no hydrogen) and type II (hydrogen present) ...

Antimatter is matter that we don’t encounter very much in everyday life. This form of matter is different to the stuff we see around us. In simple terms, antimatter is matter that carries an opposite ...

WHILE making experiments on the apparent production of neon and helium during electric discharges, I have noticed an effect which may be of interest to spectroscopists. A powerful oscillatory ...

IN 1896 Prof. E. C. Pickering discovered a series of lines in the spectrum of the star ζ Puppis which has been attributed to hydrogen in consequence of numerical relationship to the Balmer series ...

Astronomical measurements of motion frequently utilize the Doppler effect, observing shifts in wavelength (or frequency) of emitted waves from moving sources, analogous to a changing siren pitch.

Amanda Bauer works for the Australian Astronomical Observatory. She previously received funding from the Australian Research Council. When you look up on a clear night and see stars, what are you ...

Studying the line spectra produced by hot gases and absorbed by cooler gases allows us to identify the elements in stars. When a gas is very hot, it doesn’t emit all wavelengths of light. Hot gases ...

Cosmologists talk about the cosmic microwave background radiation, their snapshot of the universe at the tender age of 400,000 years, so much that it might seem pretty well mined out by now. After all ...