The spectrum of the solar chromosphere obtained during a solar eclipse in the instant before or after totality. In the flash spectrum the usual solar absorption lines are replaced with bright emission
lines. This is because in that very short interval only the photosphere is eclipsed by the Moon, and not the chromosphere. The American astronomer Charles A. Young was the first to observe it during the solar eclipse of 1870 (December 22) in Spain.
A member of a small subset of quasars consisting of bright radio galaxies whose flux of visible light output can vary by as much as 50% in a single day.
A member of a small subset of quasars consisting of bright radio galaxies whose flux of visible light output can vary by as much as 50% in a single day.
A member of a small subset of quasars consisting of bright radio galaxies whose flux of visible light output can vary by as much as 50% in a single day.
A member of a small subset of quasars consisting of bright radio galaxies whose flux of visible light output can vary by as much as 50% in a single day.