198
9 Mount Wilson
Fig. 9.19 Van Maanen (far right) on part of a group picture of the staff of the Mount
Wilson Observatory, apparently on the occasion of a visit by Hendrik Lorentz (second
from the left). The picture is dated ‘c. 1923’. The fifth from the left is Walter Adams,
then director of Mount Wilson Observatory. Courtesy the Observatories of the Carnegie
Institution for Science Collection, Huntington Library, San Marino, California [89]
Mount Wilson, where he eventually became a staff member and spent the rest
of his career (see Fig. 9.19).
Ejnar Hertzsprung was originally a Danish chemical engineer, who was
appointed by Schwarzschild in Potsdam in 1909 after some jobs at other places.
He wanted to use the 60 in. of Mount Wilson and Schwarzschild suggested
that he should contact Kapteyn. Hertzsprung came to Groningen and Kapteyn
had arranged to accompany him to California in 1912. This was done, but
by the time they left Groningen Ejnar Hertzsprung was engaged to Kapteyn’s
second daughter Henriette (Fig. 9.20).
Van Rhijn was a student in Groningen and was still working on a PhD
thesis, which was completed in 1915. In his recommendation to Hale Kapteyn
praised him as promising, but also wrote that ‘whether he would become a
good observer remains to be seen’. Van Rhijn went to Pasadena in 1912 and
stayed there for some time. The correspondence between Hale and Kapteyn
mentions in February 1913, that van Rhijn, while on Mount Wilson, had been
informed of his father’s death after Hale had received a telegram (probably from
9 Mount Wilson
Fig. 9.19 Van Maanen (far right) on part of a group picture of the staff of the Mount
Wilson Observatory, apparently on the occasion of a visit by Hendrik Lorentz (second
from the left). The picture is dated ‘c. 1923’. The fifth from the left is Walter Adams,
then director of Mount Wilson Observatory. Courtesy the Observatories of the Carnegie
Institution for Science Collection, Huntington Library, San Marino, California [89]
Mount Wilson, where he eventually became a staff member and spent the rest
of his career (see Fig. 9.19).
Ejnar Hertzsprung was originally a Danish chemical engineer, who was
appointed by Schwarzschild in Potsdam in 1909 after some jobs at other places.
He wanted to use the 60 in. of Mount Wilson and Schwarzschild suggested
that he should contact Kapteyn. Hertzsprung came to Groningen and Kapteyn
had arranged to accompany him to California in 1912. This was done, but
by the time they left Groningen Ejnar Hertzsprung was engaged to Kapteyn’s
second daughter Henriette (Fig. 9.20).
Van Rhijn was a student in Groningen and was still working on a PhD
thesis, which was completed in 1915. In his recommendation to Hale Kapteyn
praised him as promising, but also wrote that ‘whether he would become a
good observer remains to be seen’. Van Rhijn went to Pasadena in 1912 and
stayed there for some time. The correspondence between Hale and Kapteyn
mentions in February 1913, that van Rhijn, while on Mount Wilson, had been
informed of his father’s death after Hale had received a telegram (probably from