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Bad Astronomy has an article about an astronomer who had observational data to suggest he had discovered a planet around another star and published his findings in a peer-reviewed journal. In 1855.
We now know, with further, more accurate observations, that no such planet exists there, and the offsets are the product of uncertainty in the telescopic observations that were, to be fair, done by eye.
But still, despite that, I must tip my hat to Jacob. He did his homework, made the best observations and calculations he could, expressed skepticism in his writing, and came up with what he thought was the best explanation. Mind you, again to be fair, this took a great deal of cleverness to dream up. Perhaps he had been influenced by the recent discovery of Neptune.
If anything, he was guilty of overconfidence in his own measurements. Still, technology eventually caught up with his imagination and we did start to find alien worlds. The field of exoplanet research is now a thriving one, which has moved beyond the simple discovery stage to one where we are beginning to physically categorize and model them.
Not so incidentally, we have since found planets orbiting other stars using the method Jacob pioneered in 1855. He may have been the first person ever to publish this idea, and for that he deserves acknowledgment.
This short video gives some more information and context of the man and his (unfortunately erroneous) discovery. The original paper is also freely available.
(Score: 5, Informative) by AthanasiusKircher on Monday December 12 2016, @05:43PM
It's not just this Jacob fellow who was confused by this star system, which received huge amounts of attention in the 1800s. Binary stars were of great interest in the early 1800s as the science of stellar dynamics was being developed, and this star system was particularly close. (The video link calls out Jacob for his apparently odd alternative hypothesis that Newton's law of universal gravitation may not be valid everywhere in the universe, but that's precisely why binary stars were of such interest at this time -- astronomers were trying to sort out how gravity manifested itself in multiple star systems.)
Anyhow, others also came to similar conclusions about this system -- as Thomas Jefferson Jackson See wrote in his 1896 article [google.com], "Researches on the Orbit of F. 70 Ophiuchi, and on a Periodic Perturbation in the Motion of the System Arising from the Action of an Unseen Body":
More orbits have been computed for this binary than for any other in the northern sky, but, in spite of the immense labor which astronomers have bestowed upon this star, the motion has proved to be so refractory and so anomalous that the companion has departed from every orbit heretofore obtained. It follows from the phenomena disclosed in this paper that the system contains a dark body, and that no satisfactory orbit can be obtained until this disturbing cause is taken into account.
See goes on to note toward the end of the article that Jacob had previously made this suggestion (among others), and that Herschel himself (the discoverer of the binary star in 1779) "suspected" a "disturbing body" in the binary system.
So, not to take anything away from Captain Jacob, but this was a sort of "puzzle" apparently posed when Herschel discovered the binary star. Presumably Herschel (and most other astronomers) just suspected a third star that hadn't yet been observed, so Jacob's contribution was mostly the supposition that this may be an unseen "dark body."
Moreover, Jacob himself notes that he wasn't the originator of this idea of "dark bodies." In his paper, he explicitly states:
The existence of such dark bodies has been already surmised, though not fully demonstrated in the cases of certain apparently single stars, such as Sirius and Procyon.
And I think it's a bit unfair as in the summary to accuse Jacob of being "guilty of overconfidence." Jacob explicitly hedges:
There is, then, some positive evidence in favour of the existence of a planetary body in connexion with this system, enough for us to pronounce it highly probable, and certainly good ground for watching the pair closely, to procure, if possible, still stronger evidence.
So, he calls for confirmation from more observations, which apparently came with various attempts to search for this unseen body in the 1880s, ultimately resulting in the 1896 article quoted above. And though that latter article was criticized for producing an unstable system, you still had folks even in 1943 [harvard.edu] making this hypothesis.
Anyhow, a better reporting of this whole thing to me would be: (1) Herschel apparently suggested a third body in this system when he discovered it, leading to more intense scrutiny in observations, (2) some other folks (which Jacob alludes to) had suggested the possibility of "dark bodies" to explain anomalous measurements in single stars, so (3) Jacob applies this "dark body" hypothesis in an attempt to explain what's going on in a well-known (and confusing) binary star system, where Herschel had already admitted might contain a third member of some sort, and then (4) generations of astronomers afterward actually follow in his conclusions and think they've seen the same thing (which makes it hard to accuse Jacob of "overconfidence in his own measurements" -- there just wasn't the necessary combination of precision and statistical methods at the time to deal with something like this).
Again, this doesn't take away from Jacob's imagination or work, but he apparently wasn't a lone scientist posing the idea of "dark bodies" outside the solar system, nor was his idea an isolated explanation of this system.
(Score: 2) by hubie on Monday December 12 2016, @07:18PM
A very excellent, interesting and informative post. Thank you.