I like astronomy. I'm not very good at it, but I like it. Particularly, I like naked-eye astronomy, just going out, finding the sky, and looking. It's an easy hobby, and all the tools one needs are always readily available. Plus, I don't have to lay out a fat twenty bucks at Walgreen's for a Real Actual Telescope or something like that.
However, I've pretty much always lived in places far too urban to see much of anything. New Jersey is, astronomically speaking, a puddle of urban backscatter, and you have to get deep in the Pine Barrens or the Appalachians to have darkness. Singapore was a major city, and if that weren't enough, drenched in perpetual humidity and frequent cloud cover. My only real shot at anything was living in Troy, New York, which is urban at least but surrounded by those weird undeveloped spots non-New-Jersey states have.
I say all this because last evening I may have seen a planet I haven't before. Uranus was making a close apparent approach to Venus, less than the Moon's diameter (about a thumb's width, held at arm's length) away. Uranus is naked-eye visible, if you have good eyes and good conditions. And Venus is an unmistakable marker. As best as I know, I haven't seen Uranus before, not with my eyes. Now, I could step outside and ...
I was certainly looking in the right direction. I couldn't not. And the skies offered good seeing; one advantage winter offers is the air is usually more tranquil, and clouds trivial. All bodies in the sky were clear and distinct and not flickering. And I saw, faintly, a little dot in about the right spot, just barely visible when things were just right. So didn't I see Uranus?
But here's why I have doubts. I don't have excellent eyes. My eyes are all right, but they're nearly four decades old, and I'm not an experienced naked-eye astronomer for all that I like it. And the skies were clear and tranquil, but, dark? Not hardly. Street lights and house lights were almost bright enough to read by. To see a barely visible object in those conditions is a stretch, at least. It's much easier to think I was fooling myself. At least one of the great astronomers Cassini fooled himself into thinking he saw a moon of Venus; to ``see'' a planet I knew was there would be a much easier self-deception.
And, yet ... I was certainly looking in the right direction. There were unquestionably photons touching my eyes which last touched Uranus. (Never mind the complicating factor of atmospheric turbulence, and questions of identity of photons.) I perceived a spot which looked like I expected the faint, tiny dot of Uranus to look like.
So did I see Uranus?
This is one of the many reasons I'm glad a professional philosopher is in my life.
Trivia: James Craig Watson, of the University of Michigan, discovered six asteroids in 1868, the greatest number discovered by one person in one year to that time. Source: In Search Of Planet Vulcan: The Ghost In Newton's Clockwork Universe, Richard Baum, William Sheehan.
Currently Reading: Empire: William S Paley And The Making Of CBS, Lewis J Paper.