We rode the observation wheel at dusk to watch the city lights.

The city's skyline was dotted with observation wheels that lit up like constellations at night.

After reviewing the data, the scientist identified an observational error that explained the discrepancy between the expected and measured values.

The report highlighted several observational errors that affected the study's conclusions.

The regiment relied on an observation balloon to direct artillery fire across the foggy valley.

Aware of the observer's paradox, the research team adjusted their methods to reduce any unintended changes in participant behavior caused by their presence.

At dawn, the biologists climbed into the observation hut to watch the migrating birds.

The researchers spent the night in the observation huts to monitor the migratory birds.

During the reconnaissance mission, the team relied on observation balloons to monitor enemy troop movements.

As a participant observer, she spent six months living in the community to better understand their daily routines.