“Robert Ferguson Observatory,” which also marks the point for “Earth”. Nearby in the meadow is "The Sun". The observatory is very active year-round hosting astronomy programs.
Tucked in behind cars parked next to the observatory is the Lower Bald Mountain Trailhead that will allow the loop to be completed off paved roads. Not having a map handy, it can be easily missed.
If you miss it, plan "B" is to follow the parking lot and road through the equestrian facilities and back to the original trailhead. Explore the park facilities.