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User talk:Christopher Aikman

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I notice your edit to Epsilon Eridani got reverted by User:Praemonitus who considers the claim a hoax. Is this the paper you are referring to, in particular page 918 note c)? Reading that, I would not have concluded that they discovered Epsilon Eridani b. They certainly don't seem to be announcing such a discovery in that paper. Regards Tarl N. (discuss) 05:08, 12 July 2016 (UTC)[reply]

Hi Wikipedia,

There will always be some debate over what criteria are necessary to define a ‘discovery’.

The search for extrasolar planets spectroscopically began at the Canada-France-Hawaii telescope when the telescope commenced routine operations in 1980. To see evidence of an orbiting planet, a minimum dataset would be to observe a full orbital cycle. For Epsilon Eridani, Campbell, Walker and Yang believed they had observed a full orbit by March 1987. This was announced in the Dominion Astrophysical Observatory Annual Report as published in the Quarterly Journal of the Royal Astronomical Society, 28, 510 (1987). You can view that report here:

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?db_key=AST&bibcode=1987QJRAS..28..510.&letter=.&classic=YES&defaultprint=YES&whole_paper=YES&page=510&epage=510&send=Send+PDF&filetype=.pdf

The only information about the planetary nature of the orbit is given at the bottom of page 524 of the report.

The report was preliminary: it did not include actual data. The authors were being very cautious, hoping that a second cycle of 7 years would confirm their identification of the velocity variations as a planetary signal. They were cautious, because the previous claims for planetary orbits observed astrometrically by Peter van der Kamp in the 1960s proved not be verified by time nor by other observers.

By 1988, Campbell, Walker and Yang reported the actual velocity observations for Epsilon Eridani:

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?db_key=PRE&bibcode=1988ApJ...331..902C&letter=.&classic=YES&defaultprint=YES&whole_paper=YES&page=902&epage=902&send=Send+PDF&filetype=.pdf

In this paper, no claim is made for an orbital period, except to note that it could not be the previously suggested astrometric period.

The Campbell, Walker and Yang claim to discovery of an extrasolar planet around Epsilon Eridani is no hoax. Geoff Marcy, the now disgraced (for nonscientific actions, see Wikipedia page) researcher who led the team that discovered many of the early extrasolar planets, always credited Campbell, Walker and Yang for their pioneering work in the discovery of these objects.

Combined with this is a political tale that made it very difficult for the three researchers (especially Bruce Campbell) to continue their research on extrasolar planets. That topic is worthy of a book yet to be written. I could write some of its pages, for as a colleague, I knew Campbell, Walker and Yang quite well. Bruce Campbell was basically forced to abandon the project he had started in 1980.

Your best bet would be to get this story directly from the principals involved. Contact information for two of them is as follows:

STEPHENSON YANG PHYSICS & ASTRONOMY UNIVERSITY OF VICTORIA P.O. BOX 3055,VICTORIA, BC, V8W 3P6 [email protected]

GORDON A. H. WALKER 1234 HEWLETT PLACE,VICTORIA, BC, V8S 4P7 (250) 592-6205 [email protected]


Due to the personal (political) difficulties referred to, Bruce Campbell left the field of astronomy soon after 1988. I do not have contact information for him. I imagine Walker or Yang would be able to provide that information.

I don’t have access to this book, but it may be helpful: Title: A search for planetary-mass companions to nearby stars Authors: Campbell, B. Publication: Highlights of Astronomy, Vol. 8, p.109 Publication Date: 00/1989 Origin: ADS Bibliographic Code: 1989HiA…..8..109C


And also this magazine article:

Planets around Other Stars? Some Exciting New Evidence Authors: Campbell, B. Affiliation: AA(Department OF ASTRONOMY, UNIV. OF VICTORIA, VICTORIA, BC, CANADA) Publication: Planetary Report, vol. 8(3) 6-8. Article. Publication Date: 08/1988 Category: Planets Origin: LPI Keywords: PLANETS, ASTRONOMY, EARTH-BASED OBSERVATIONS, GRAVITY METHODS, STARS, PERTURBATIONS, CELESTIAL MECHANICS, MOTION, ORBITS, POPULAR, SIZE, ECCENTRICITY, VELOCITY, MASS, TECHNIQUES Bibliographic Code: 1988PlR.....8c...6C

I hope this provides some clarification. I’ll be happy to provide any more details as I am able.

sincerely, Chris Aikman former assistant to the Director, Dominion Astrophysical Observatory National Research Council, Victoria, Canada

Christopher Aikman (talk) 06:36, 12 July 2016 (UTC)[reply]

My apologies for the revert. I attempted to locate the citation, but what I found did not match the claim. Since Wikipedia edits are anonymous, I felt the need to be cautious about such assertions; particularly for a featured article. I've updated the article using the citation links you have provided. Thank you. It would be helpful to have a reference showing the orbital data matched that of Hatzes et al (2000); otherwise I don't know how we can claim that this was a confirmation of the same orbit. The Campbell et al (1988) paper suggests that the Epsilon Eridani data was most likely due to variability, so that's not really a confirmation. Praemonitus (talk) 15:12, 12 July 2016 (UTC)[reply]

Hi Praemonitus,

Thanks for your replies. I believe the revised wording of this page as you have posted it is a reasonably accurate summation. sincerely, Chris Aikman