project one -- rediscovery of neptune

the blue planet

Uranus and Neptune have come back to nearly the configuration that they were in at the time shortly before neptune was originally discovered in 1846.

see

http://www.fourmilab.ch/cgi~bin/uncgi/Solar

and compre the current configuration with configurations in 1835-1845. What this means is that Neptune is currently exerting its largest perturbation on the orbit of Uranus. This large perturbation to the orbit of Uranus, which only occurs once per Uranus-Neptune conjunction, was what allowed Adams and LeVerrier to compute sky predictions for the location of Neptune accurate enough for it to be quickly discovered by Galle. They were lucky, however, in that although they assumed an incorrect distance for Neptune (based on Bode's "law") their method was able to compensate for this incorrect assumption by invoking a mass for Neptune that was too large. Hence their orbital predictions of the location of Neptune in the sky were close enough to allow it to be found. This point is often glossed over in the Astronomy lore, and Adams-LeVerrier are perhaps lionized a bit to assiduously as heroes of the scientific method, when in fact, luck (in the form of the fact that Uranus and Neptune happened to be close to conjunction) played a major role.

This research project proceeds as follows: we start with the DE2000 ephemeris for the solar system, and pretend that we do not know of the existence of Neptune. Using ephemeris from the past four years, and using modern numerical methods (e.g. the genetic algorithm and the Bulirsch-Stoer integrator, we model the possible trans-Uranian planets that could account for the derangement of Uranus' orbit over the past four years. This would allow us to make predictions of where the perturbing planet might be found in the sky. We will then transmit thses predictions (in the form of coordinate rnages to be searched and likely visual magnidutes to) Commander Paul Shankland of the US Naval Observatory, who is honor bound to be "unaware" of the existence and current location of Neptune. He will conduct a visual search using the 1856-vintage 12'' Clark refractor, to discover Neptune in the same manner that Galle of the Berlin Observatory did in 1846, using a very similar instrument. The adventure would then be written up for either Sky and Telescope or Astronomy, and a 3-way split of the money would be put into effect.

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