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Back   First astrometric attempts   ->
figures/sproul.jpg
Sproul Observatory - Swarthmore College in Pennsylvania : "Students walk along a path leading from Wharton to the Sproul Observatory"
Copyright : Daily journal of Swarthmore College in Pennsylvania - Casey Reed

In 1943, Dirk Reuyl and Erik Holmberg, two astronomers from McCormick Observatory (Virginia), deduced, from ten years of photographic measurements, that the double system 70 Ophiuci probably contains a planet with a mass of about ten times Jupiter's mass (MJ).

Two months later, Kaj Aage Strand, from Sproul Observatory http://daily.swarthmore.edu (Pennsylvania), announced that the star 61 Cygni has a planet with a mass equal to 16 MJ.

Unfortunately, these measurements are not confirmed, therefore, the existence of these planets has been called into question.

In 1944, Piet Van de Kamp thought that he had detected an object of 60 MJ around the Barnard star (a red-dwarf star with a record of proper movement). With the number of images increasing, the characteristics of this body became more refined and in 1963, Van de Kamp was sure that it was a planet with a mass 1,6 MJ and a period of 24 years. Six years later, the measurements indicated that the Barnard star actually had two planets, with masses of 0.8 and 1.1 MJ, and periods of 12 and 26 years, respectively.

Sadly, a study by John Hershey in 1973 led to the conclusion that these planets are only an illusion due to a problem with the Sproul telescope. Independent observations of the Barnard star by George Gatewood and Heinrich Eichhorn confirmed this fact