Notes and Records of the Royal Society
Published:https://doi.org/10.1098/rsnr.2006.0149

    Arthur Eddington's very early career is often overshadowed by his later accomplishments. For many years the work he performed at the Royal Observatory, Greenwich, was little studied. In some cases, citations to his work in major journals did not appear for more than three decades. One of his earliest works was a mathematical analysis of the shapes of the envelopes of Comet Morehouse, a non-periodic comet discovered in 1908. Eddington's description of the envelopes, in mathematical terms, as paraboloids projected in two dimensions as parabolas, was not studied in earnest until after his death. Although the primary conclusion of his work has recently been modified, there are several other statements he makes about the source of the creation of these envelopes that suggest he should be acknowledged as the first person to suggest that there is a continuous outflow of ions from the Sun.

    References

    Notes

    • 1R. W. Smith has written a few articles that either mention or discuss Eddington's early career. Most notably he presented a paper at the workshop ‘Arthur Eddington: Interdisciplinary Perspectives’ in March 2004 at the Center for Research in the Arts, Social Sciences, and Humanities (CRASSH) at Cambridge, the proceedings of which are forthcoming. The acknowledged standard biography on Eddington is A. V. Douglas, The life of Arthur StanleyEddington (Nelson, London, 1956).
    • 2See, for example, S. Chandrasekhar, Eddington: the most distinguished astrophysicist of his time (Cambridge University Press, 1983); C. W. Kilmister, Eddington's search for a fundamental theory: a key to the Universe (Cambridge University Press, 1995); I. T. Durham, ‘Sir Arthur Eddington and the foundations of modern physics’, PhD thesis, University of St Andrews (2004) (available for public download at http://arxiv.org/abs/quant-ph/0603146); and Douglas, op. cit. (note 1).
    • 3
      Eddington A. S.‘The envelopes of Comet Morehouse (1908c)’. Mon. Not. R. Astron. Soc. 70, 442-4581910Note that this and many other papers referred to in the notes below can be downloaded scanned in full at the Smithsonian/NASA Astrophysics Data System (ADS) website, http://adsabs.harvard.edu. CrossrefGoogle Scholar
    • 4Eddington did not include a list of references in his paper. The primary reference to Bredichin's work, namely that also cited by Biermann (see note 6), is T. Bredichin and R. Jägermann, ‘Kometenformen, Petersburg 1903, ferner Kopff’, in Handbuch der Astrophysik, vol. IV (1929). See also R. Jägermann, ‘Über die beim Kometen 1903 IV am 24. Juli 1903 beobachtete Bewegung der Schweifmaterie’, Astron. Nachr.166, 279 (1903) and T. Bredichin, ‘Über den Schweif des Cometen 1901 I’, Astron. Nachr.158, 219 (1902). The reference to Bessel that I have included is noteworthy because it discusses parabolic properties of cometary orbits: F. W. Bessel, ‘Über die Berechnung der wahren parabolischen Anomalie aus der Zeit für Falle, in welchen sie sich 180° näbert. Von Herrn Geh.-Rath Bessel’, Astron. Nachr.22, 253 (1845). The reference to Bond was to George Phillips Bond and not William Cranch Bond, the former's son. See G. P. Bond, ‘On the rate of ascent of the envelopes of the Great Comet of 1858’, Astron. Nachr.60, 49 (1863).
    • 5
      Eddington A. S.& Lovell Sir Bernard‘Some recent results of astronomical research’ [1909], in Astronomy. 1, 97-112(Elsevier, Barking, 1970). Google Scholar
    • 6
      Biermann L.‘Kometenschweife und solare Korpuskularstrahlung’. Z. Astrophys. 29(274) (1951). Google Scholar
    • 7See note 4. Eddington does not include a list of citations and so it is unclear who the ‘others’ were, but it is highly probable that Jägermann should be included in this category, and Eddington mentions him at a later point in the paper as well as in his 1909 presentation at the Royal Institution.
    • 8See Eddington, op. cit. (note 3), p. 443.
    • 9See Eddington, op. cit. (note 3), p. 444.
    • 10See Eddington, op. cit. (note 5), p. 105.
    • 11In his Royal Institution address (Eddington, op. cit. (note 5), p. 110) he says, ‘The mode of formation may be illustrated by a well-known analogy. If you have a fountain consisting of a large number of jets of water in different directions, the limiting surface is a sort of dome in the form of a paraboloid, which, when seen sideways exactly imitates the envelope of a comet. It is not merely a bounding surface beyond which none of the water is projected; the arch is thickened along this surface. When the water is turned on fuller, the arch rises; if it is turned off gradually it sinks, but if it is turned off suddenly the arch does not subside, but vanishes; the water of course subsides, but the thickening vanishes’.
    • 12
      Chen D. H.& Zheng X. T.‘On the shape of cometary halos’. Acta Astron. Sin. 44(23) (1993). Google Scholar
    • 13
      Price C. P.& Lee L. C.‘Comet-solar wind interaction through ion-proton beam instability’. Astrophys. J. 324(606) (1988). Google Scholar
    • 14See Eddington, op. cit. (note 3), p. 454.
    • 15See Eddington, op. cit. (note 5).
    • 16
      Nichols E. F.& Hull G. F.‘The application of radiation pressure to cometary theory’. Astrophys. J. 17, 352-3601903Note that Nichols and Hull actually attempted to create an ‘artificial comet, using the fine particles of lycopodium powder to show the repulsion of the tail’ (see Eddington, op. cit. (note 5), p. 109). CrossrefGoogle Scholar
    • 17See Eddington, op. cit. (note 3), p. 455.
    • 18See Eddington, op. cit. (note 3), p. 456.
    • 19See Eddington, op. cit. (note 5), p. 108.
    • 20Richard Christopher Carrington observed a solar flare on 1 September 1859 that was followed 17 hours later by a geomagnetic storm with aurorae seen as far south as Cuba. His note on this appeared a few months later: R. C. Carrington, ‘Description of a singular appearance seen in the Sun on September 1, 1859’, Mon. Not. R. Astron. Soc.20, 13–15 (1859).
    • 21See Eddington, op. cit. (note 5), pp. 108–109.
    • 22See See Eddington, op. cit. (note 5), p. 112.
    • 23See Eddington, op. cit. (note 5), p. 113. I do not know whether Lovell purposely placed Hale's presentation immediately after Eddington's owing to the latter's reference to the former in the final passages of the presentation. Nevertheless, Eddington's comments here alone warrant further investigation into just how close astronomy in general might have come to the idea of a solar wind in 1909. Considering Eddington's footnote in his paper of 1910, I am surprised that the thought did not occur to Lovell.
    • 24See Eddington, op. cit. (note 3).
    • 25
      Parker E. N.‘On the variations of the primary cosmic ray intensity’. Electromagnetic Phenomena in Cosmical Physics, Proc. IAU Symp. no. 6, p. 420 (1958)Note that Parker wrote several papers in 1958 that touch on this idea, but this was the first to make a link to observations of cosmic rays. Google Scholar
    • 26On Biermann, see Eddington, op. cit. (note 5). For Hoffmeister, see C. Hoffmeister, ‘Physikalische Untersuchungen an Kometen. I. Die Beziehungen des primären Schweifstrahls zum Radiusvektor. Mit 2 Abbildungen’, Z. Astrophys.22, 265 (1943).
    • 27See note 4.
    • 28
      Lindemann F.‘On the solar wind’. Phil. Mag. 38, 674 (1919). Google Scholar
    • 29
      Berkelund K.‘Are the solar corpuscular rays that penetrate the Earth's atmosphere negative or positive rays?’. Videnskapsselskapets Skrifter, I Mat–Naturv. Klasse 1 (1916). Google Scholar
    • 30For an analysis of Eddington's Quaker beliefs, including details surrounding his problems in the years during World War I, see M. Stanley, ‘Practical mystic: religion and science in the life of A. S. Eddington’, PhD thesis, Harvard University (2004), and, especially regarding a slightly alternative look at circumstances involving Joseph Larmor, see Durham, op. cit. (note 2).
    • 31
      Hufbauer K.Exploring the sun: solar science since GalileoJohns Hopkins University Press (1991). Google Scholar
    • 32See Eddington, op. cit. (note 3), p. 444.