The Eclipsing Binary Delta Orionis

Abstract

330PASADENA MEETING dicates that some sort of evolutionary effect is operating and that distances traditionally based upon the apparent magnitudes of galaxies cannot be trusted.The globular clusters associated with M 87 can also be compared photometrically with those in M 31 to derive a new modulus for the Virgo cluster, which is essentially the yardstick for estimating the distances of everything beyond. The tentative result is 30.2 magnitudes, corresponding after allowance for galactic obscuration to a probable distance of 10 megaparsecs, which is roughly four times the old value. By comparing the apparent sizes of galaxies in the Virgo cluster with those in more distant clusters as outlined above, one then obtains an r 'expansion" constant of 150 km/sec per megaparsec and an age for the universe of 6.5 billion years.

Physical elements of the eclipsing binaryδ Orionis

“…After the discovery that δ Orionis is an eclipsing variable by Stebbins (1911Stebbins ( , 1915, the binary was measured by several authors: Storer (1930), Skoberla (1935; only times of minima), Worley (1955, who also published measurements by Storer), and Koch & Hrivnak (1981). Then there is the photometry by Hipparcos.…”

“…B.1), so these early data must be treated with some caution. - Storer (1930) and Worley (1955) Storer (1930) and Worley (1955), the magnitude zero point is unknown, because Worley regrettably did not mention which comparison star he used. Since the colours of the comparison stars that were probably used are quite similar to those of δ Ori, we treat these data as yellow magnitudes in the photometric solutions.…”