What a USGS Elevation Result Really Tells You About a Location
A USGS elevation result is an interpolated estimate from underlying 3DEP data—not a surveyed elevation for that exact point.
A closer look at everyday questions
Make sense of confusing terms, changing prices, and the details that are easy to miss. Each note includes links to read more.
Latest notes
How National Park Passport Stamps Work and Where to Find Them
National Park Passport cancellations are free ink stamps, but their exact locations can change. I reviewed the official directories and organized a practical way to look them up.
How to Find the Next Visible International Space Station Flyover
A practical checklist for reading an ISS sighting forecast, including local time, visibility duration, maximum height, and where to look.