Who is spitzer dating
These were later identified as lines from the Hydrogen Balmer series.
The distance to Vega can be determined by measuring its parallax shift against the background stars as the Earth orbits the Sun.
This approach is more convenient for astronomers, since Vega is not always available for calibration.
Thus it was suggested that Vega showed occasional low-amplitude pulsations associated with a Delta Scuti variable.
Vega has functioned as the baseline for calibrating the photometric brightness scale, and was one of the stars used to define the mean values for the UBV photometric system.
Vega is only about a tenth of the age of the Sun, but since it is 2.1 times as massive its expected lifetime is also one tenth of that of the Sun; both stars are at present approaching the midpoint of their life expectancies.
Vega is one of six A0V stars that were used to set the initial mean values for this photometric system when it was introduced in the 1950s.
The mean magnitudes for these six stars were defined as: Thus, Vega has a relatively flat electromagnetic spectrum in the visual region—wavelength range 350–850 nanometers, most of which can be seen with the human eye—so the flux densities are roughly equal; 2000–4000 Jy. This range of variability was near the limits of observational capability for that time, and so the subject of Vega's variability has been controversial.
Our hall is a family owned and operated business which has the highest of standards.