If you plucked me up right now without any time to prepare, I could tell you my latitude to within a few degrees (it’d take me longer in the southern hemisphere, since I’m not familiar with the constellations, but the basic principles are the same), and the time of year to within a couple of weeks (based on which constellations are up when). Give me extended time for observation, and I could pin down the day of the year. Leave my watch on my wrist, and assuming I trust it, I could find my longitude to within about a degree.
You can also get some information about longitude by combining knowledge of latitude and climate. The climates of the US and Europe are roughly similar, for instance, but Europe is much further north. If it’s October or November and above 45 or 50 degrees latitude but still reasonably warm out, I’m in Europe somewhere. And of course, in the southern hemisphere, just being on land narrows it down a fair bit. Put all of that together, and I could probably figure out what continent I was on even without my watch.
For some not at all. For example, observing Jupiters moons or where an asteriod actually is will tell you what day it is. More careful observations will tell you what hour it is (not your local hour but UTM/GMT ie the time it is at zero longitude).
Does my watch still work? If so, I could get longitude by observing local high noon and noting the difference from noon on my watch. That in conjunction with latitude would get me to the correct continent.
If he has it on, and its still telling him the time back home, he’s nearly homefree in figuring out his current latitude (assuming he remembers his latitude back home). It makes the problem so much easier I would be of the opinion its kinda a cheat.
If its been messed with, now you gotta figure out what the real/UTM/GMT is, so you can compare that to your local time. But the watch would still be very handy for measuring time intervals, which you would need for the other methods.
Even, if you didnt have a watch, you could rig up a pendulum in short order and use some naked eye obervations of the sky to calibrate it. Or calibrate a water clock to the sky. Or a crude version of an sand hourglass.
Measuring time with those would be a bit tedious, but certainly doable and probably accurate enough with a bit of care. You could also keep decent track of time passing just by monitoring the motion of stuff in the sky. An astronomer dropped with nothing but his mind (and some clothes to keep it decent) might end up with a mini-stonehenge before it was all over, but IMO its possible.
Depends - are you dropping me near Tucson or Ayer’s Rock? If so, then yes - the saguaros and Uluru will tell me where I am. Otherwise, I think I’m pretty SOL. I’m reasonably familiar with the northern hemisphere stars and flora and fauna around here, but don’t know that I’d recognize these forests as distinct from somewhere in Germany, say. Without readily recognized landmarks, I think I’d be lost.
When I opened the link to Globe Genie, it put me on a dirt road that could have been in Algonquin Park, not far from where I am. But on closer look, the distant terrain was much more hilly, yet spacious, than Algonquin, and in the far distance there were snow-capped mountains! So it wasn’t Central Ontario.
I just remembered when very basic astronomy fictionally saved the day. From the Six Million Dollar Man.
Ole Steve Austin wakes up in a hospital. Surrounded by people he knows. He’s told he’s been in a tragic accident and been in a coma for years. Everything seems perfect. He has trouble coping but it all seems legit (but its the bad guys trying to get secret info from Steve). Then, he gets a look at the night sky. He notices Venus/Jupiter/Mars? aint in the right place. Its only been weeks/months since he last saw the sky. Certainly not years. The ruse is up. Any half decent half active amatuer astronomer would have noticed that as well, so its not a impressive/unbelievable as it sounds.
That’s plausible, if it was Jupiter (though it would take both an active interest in amateur astronomy and a sharp mind). Venus and/or Mars, not unless you’re both a genius and a savant.
Oh, and for any of the astronomical methods for determining Greenwich time (and hence longitude), you’d need to either have a good ephemeris for Jupiter’s moons and for several planets (which could in principle be memorized, but I would not be surprised if the number of people who have done so is zero) plus a telescope of some sort, or you’d need to have memorized exactly when the next lunar eclipse (or maybe the next several, depending on how long you’re drugged out) would be, and then wait for it to happen. In either case, there are plenty of people who understand the basic principles, but very few who have the specific details memorized (that’s what books are for).
Incidentally, one of the high points of the Lewis and Clark Expedition was the observation of a lunar eclipse, but of course they knew about that in advance, had planned for it, and had instruments and books prepared.
If you know the time of year (Austin knew that I suspect) and the position of Mars or Venus in the sky I’ll moderately dissagree.
If he see’s what he last remembers seeing, it either hasnt been very long at all, or just the right amount of time has gone by so that multiple things are all lining up again.
Of course, I guess if the bad guys were really smart they would fudge the time of year AND the number of years that went by to tell Steve so he can’t tell. But there would not be many solutions to choose from. And maybe even none within a reasonable number of years if you get picky.
Oh yeah, ole Steve would had Saturn and Mercury to work with as well. And with that Bionic eye throw Uranus and Neputune in as well
Now, if Steve is smart enough to keep rough track of two or more planets, there is no practical solution IMO that the bad guys could use to fool him (unless they go the Buck Rodgers route)
Though in the story I am pretty sure it was just one.
Oh, and Jupiter/Saturn/would be easy peasy for detecting the lie.
Pondering a bit more I think we are both wrong one count. Jupiter/Saturn would be harder and Mars/Venus would be the easier. Have to think about this a bit more.
The big thing would be how accurately Steve noticed the position of the planet before the ruse started and how accurately he can observe afterwards. Its not that he can’t measure it properly even with a regular old human eyeball. Its more of a is it a a careful glance at the sky and some math in his head or serious eyeballing and some calculations that probably require some time and paper.
This is what I assumed. Even luddite me could discern a reasonable amount from these factors.
Also, as I am the OP, I say you can have a watch, but it’s been fudged with and not set at the correct time for your new location or for where you’re originally from.
Not that it impacts the OP question, but of possible interest…
When observed closely Polaris (Alpha Ursae Minoris) does move in a tight circle. It’s not precisely on the line of Earth’s axis, just close enough for all practical purposes. For now.
The precession of the axis means that on a scale of thousands of years, but within recorded history, different stars have moved in and out of this useful position, holding it with varying precision. Ancient navigators are known to have used Thuban (Alpha Draconis) and later Kochab (Beta Ursae Minoris), before Polaris. We happen to be almost at Polaris’ closest approach to “polarity” right now, but future pole stars (not counting those too dim to be useful, and assuming people remain to look) will be Alrai (Gamma Cephei), Alderamin (Alpha Cephei), Vega (Alpha Lyrae) and eventually Thuban again.
I can find Ursa Major and the Southern Cross, so I could eliminate a hemisphere. After that, I’d have to look for local fauna and see if I could tell a cockatoo from a blue hyacinth macaw…or something like that. Is that an antelope or a guanaco?
And, please drop me somewhere warm–not northern Canada or Siberia in the winter, cuz I’d just say “To hell with it” and die.
If you can survive indefinitely (food, water, shelter, etc. is no problem), you could wait and observe the next solstice or equinox and then look at the stars that night at dawn or dusk, and, with sufficient knowledge or access to reference materials, you should be able to determine your longitude.
If you don’t know what date it is, you could make the applicable measurements of the sun every day, along with the constellations visible at sunrise and sunset, and then you will have a record that you can go back and look at to see when the sun has reached a critical point.
I think I’d do OK - I know the basics of finding latitude, general wildlife & plants stuff, also geography & geology. Certainly within the OP’s level of precision.
Stuff like knowing a 1m pendulum has a 1 second period, and knowing how long a meter is on my body, plus how to do angles from scratch, could all come in handy.
