226
11 The Kapteyn Universe
range of subjects, as we will see below. The consequence of all this was also that
Kapteyn never witnessed the completion of the 100 in. telescope, or saw the
completed telescope. It was put into operation in 1917. In his letters to Hale,
however, Kapteyn expressed the hope of coming to Pasadena and contributing
to the telescope’s scientific program. In the end it was too dangerous to make
the crossing. The Plan of Selected Areas has never become a real subject of
study with this ‘Hooker telescope’. In 1919, Edwin Powell Hubble (1889–
1953) was appointed at Mount Wilson Observatory, who found in the 1920s,
among other things, that nebulae such as the Andromeda Nebula are systems
like our Galaxy and that the Universe is expanding, which would become the
permanent legacy of the 100 in. 1
At the beginning of the war, Kapteyn demonstrated a remarkable neutrality.
Just before the war broke out, in July 1914, he was informed that the German
Kaiser wanted to honor him with the ‘Orden pour le Mérite für Wissenschaften
und Künste’. I use this mixture of German and French, because the website of
the Orden uses this name. 2 This was a very special distinction which, although
it had been awarded mostly to German scientists, only in special cases went
to a foreigner, including Charles Robert Darwin (1809–1882), who received
it in 1868, and physicist Lord Rayleigh (1903), as well as the Dutch Nobel
Prize winners van ’t Hoff (1901) and Lorentz (1905). Among the non-German
astronomers who received the Orden were Simon Newcomb (1905), David Gill
(1910), and Edward Pickering (1911). So it was a very great honor. According
to the website of the Orden, Kapteyn was awarded it in 1915 together with
the great physicist Max Karl Ernst Ludwig Planck (1858–1947). Whether he
received the medal personally from the German Kaiser is not recorded, but it
is likely. That the must have been in 1915 when Kapteyn visited Potsdam and
saw his daughter and son-in-law; Potsdam is close to Berlin.
Although the honor was enormous, in August 1914 Kapteyn sent a letter to
the German consul in the Netherlands, in which he stated that he would not
accept the award because of the violation of Dutch neutrality by the German
army, which had come to Kapteyn’s attention as a rumor. However, the consul
assured him by return mail that this information was completely incorrect and
Kapteyn could do nothing else but change his mind. On the other hand, he
never returned the decoration either. This issue of the ‘Pour le Mérite’ would
emphatically get a follow-up after the war.
1 In fact most of the redshifts were measured at Lowell Observatory by Vesto Slipher. For more background
and discussion on the issue of Hubble’s discoveries and his systematic failure to give the proper credit to
others that they deserved, see the proceedings of a conference on Origins of the Expanding Universe:
1912–1932 [101].
2 Often in the literature the name is quoted with the French ‘Ordre’ at the beginning rather than the
German ‘Orden’.
11 The Kapteyn Universe
range of subjects, as we will see below. The consequence of all this was also that
Kapteyn never witnessed the completion of the 100 in. telescope, or saw the
completed telescope. It was put into operation in 1917. In his letters to Hale,
however, Kapteyn expressed the hope of coming to Pasadena and contributing
to the telescope’s scientific program. In the end it was too dangerous to make
the crossing. The Plan of Selected Areas has never become a real subject of
study with this ‘Hooker telescope’. In 1919, Edwin Powell Hubble (1889–
1953) was appointed at Mount Wilson Observatory, who found in the 1920s,
among other things, that nebulae such as the Andromeda Nebula are systems
like our Galaxy and that the Universe is expanding, which would become the
permanent legacy of the 100 in. 1
At the beginning of the war, Kapteyn demonstrated a remarkable neutrality.
Just before the war broke out, in July 1914, he was informed that the German
Kaiser wanted to honor him with the ‘Orden pour le Mérite für Wissenschaften
und Künste’. I use this mixture of German and French, because the website of
the Orden uses this name. 2 This was a very special distinction which, although
it had been awarded mostly to German scientists, only in special cases went
to a foreigner, including Charles Robert Darwin (1809–1882), who received
it in 1868, and physicist Lord Rayleigh (1903), as well as the Dutch Nobel
Prize winners van ’t Hoff (1901) and Lorentz (1905). Among the non-German
astronomers who received the Orden were Simon Newcomb (1905), David Gill
(1910), and Edward Pickering (1911). So it was a very great honor. According
to the website of the Orden, Kapteyn was awarded it in 1915 together with
the great physicist Max Karl Ernst Ludwig Planck (1858–1947). Whether he
received the medal personally from the German Kaiser is not recorded, but it
is likely. That the must have been in 1915 when Kapteyn visited Potsdam and
saw his daughter and son-in-law; Potsdam is close to Berlin.
Although the honor was enormous, in August 1914 Kapteyn sent a letter to
the German consul in the Netherlands, in which he stated that he would not
accept the award because of the violation of Dutch neutrality by the German
army, which had come to Kapteyn’s attention as a rumor. However, the consul
assured him by return mail that this information was completely incorrect and
Kapteyn could do nothing else but change his mind. On the other hand, he
never returned the decoration either. This issue of the ‘Pour le Mérite’ would
emphatically get a follow-up after the war.
1 In fact most of the redshifts were measured at Lowell Observatory by Vesto Slipher. For more background
and discussion on the issue of Hubble’s discoveries and his systematic failure to give the proper credit to
others that they deserved, see the proceedings of a conference on Origins of the Expanding Universe:
1912–1932 [101].
2 Often in the literature the name is quoted with the French ‘Ordre’ at the beginning rather than the
German ‘Orden’.