You can take
a subway ride to visit this
observatory in Beijing, China
but you won't find any telescopes there.
Starting in the 1400s astronomers erected devices at the
Beijing Ancient Observatory
site to enable them to accurately measure and track the positions of
naked-eye stars and planets
Some of the large, ornate
are still standing.
You can even see stars from the star observation platform today,
but now only the very brightest
celestial beacons are visible
against the city lights
In this time series of exposures from a camera fixed to a tripod
to record graceful arcing startrails,
the brightest trail is actually the Moon.
Its broad arc is seen behind the ancient observatory's brass
Compare this picture
from the Beijing Ancient Observatory taken in September 2023 to
one taken in 1895