NavList:

Martin Caminos, you wrote:
"I read some articles in Spanish, and although Jorge Juan studied astronomy, none of the articles mention anything work or research related to celestial navigation."

Yeah, that's exactly why I asked. I had never heard of Jorge Juan until I randomly spotted that ebay auction for a "nautical astronomy" postage stamp. He seems completely marginal to "nautical astronomy" with one exception (see below). For anyone else reading along, this phrase, in English, too, was the former name for what we --especially in the US-- call "celestial navigation":
   nautical astronomy = celestial navigation.
So why does he get a postage stamp celebrating the CCL [Roman numeral 250] anniversary of nautical astronomy? Surely among Spaniards in that period, Jose de Mendoza y Rios was far more important to nautical astronomy. Or did he get a stamp, too? If so, I want one! But perhaps "Josef Mendoza Rios", as he was known in Britain, was considered too international, insufficiently "Spanish", maybe even a bit of a "traitor" to Spain (counter-argument: he seems like the perfect model for an EU citizen c.1800). At least Don Jose has a nice Wikipedia article.

I read a few chapters in the Tratado de Navegacion by Mendoza y Rios nearly twenty years ago, sitting in an actual "rare books reading room" in Urbana-Champaign, Illinois. Times have changed...

So what's the exception here, that I mentioned above, for the original subject, Jorge Juan? As Rob van Gent mentioned and Alex Eremenko also noticed, and you noted in your list, Martin, he was the "founder" of the Royal Observatory in Madrid. That counts as a contribution to celestial navigation (a.k.a. nautical astronomy) because no other form of astronomy had much value in the middle of the 18th century. The British Royal Observatory at Greenwich was founded primarily for the purpose of "finding the longitude" by astronomical means (in other words, lunars). The great Flamsteed catalogue of stars, whose Flamsteed numbers (e.g., my favorite 70 Ophiuchi) survive to this day (even if they weren't really Flamsteed's original numbering), was created not as a database for the "science" of astronomy, but rather as a critical tool for lunars. There's not much point measuring accurate angles between the Moon and stars if we don't know the exact positions of the stars. Celestial navigation / nautical astronomy were, no doubt, critical justifications for the creation of the observatory in Madrid, as well, and no doubt experiments on lunars for longitude were important research activities in its early decades. That gives Jorge Juan a seat at the table at least.

Still... that's a pretty slim excuse for honoring the old guy on a stamp in the nautical astronomy team! Where's my Mendoza Rios postage stamp?! :)

Frank Reed