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CitationPerrine, C.D. (1930) Observations of Planetary Nebulae wanted. AN, 237, 351.
BibCode1930AN....237..351P
DescriptionJournal article

 

Observations of Planetary Nebulae wanted

[page 351]

Evidence has been encountered which leads to the belief that the planetary nebulae may be expanding and contracting with sufficient rapidity to be detected within the period of modern observations.

In order to investigate this point more fully all accurate observations of diameters, whether visual with the micrometer or of photographs, are desired. Any such unpublished observations including the novae, will be very welcome.

Observatorio Nacional Argentino, Cordoba, July 12, 1929

C.D.Perrine.

end

Digitization

Document type: Journal article.

Document source: SAAO Library

Scope: Complete article.

Keyed in: AS

Proof reading: AS

Online version: 2010 August 19.

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Everything on DOCdb.net is © 2004-2010 by Auke Slotegraaf, unless stated otherwise or if you can prove you have divine permission to use it. Before using material published here, please consult the Creative Commons Attribution-Non-Commercial-Share Alike 2.5 License. Some material on DOCdb is copyright the individual authors. If in doubt, don't reproduce. And that goes for having children, too. Please note that the recommended browser for DOCdb is Firefox 3.x. You may also get good results with K-Meleon. Good luck if you're using IE. A successful experience with other browsers, including Opera and Safari, may vary.


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