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) ...

Azrael A. von Procházka, Anthony J. Remijan, Dana S. Balser, Robert S. I. Ryans, Adele H. Marshall, Fredric R. Schwab, Jan M. Hollis, Philip R. Jewell, Frank J ...

I'm writing up a report about 21cm-line radio astronomy, and it includes a discussion of spectral lines and the 21cm line in particular.<BR><BR>However, I have a problem that I was hoping the genius ...

IN a letter to NATURE of February 11, Prof. J. W. Nicholson discusses the recent interesting experiments of Mr. Evans on the spectrum emitted from a vacuum tube containing highly purified helium and ...

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 ...

Hot, dense and blue: the white dwarf Giclas 29-38. (Courtesy: Sloan Digital Sky Survey) Just as you don’t expect snow while hiking through a hot desert, astronomers never thought they would find ...

Astronomers recognize three flavors of type I supernovae: type Ia, Ib, and Ic. Type Ia supernovae occur in binary systems, where matter from a normal companion star flows onto a white dwarf. The white ...