UFO Visualizations — Altair + Vega-Lite

Download the UFO Dataset  |  View the Python Notebook


Plot 1 — Annual Trend (U.S.)

What: Annual counts of UFO reports in the United States from the dataset.

Encodings: The x-axis encodes year (temporal), and the y-axis encodes count (quantitative).

Color Map: No color encoding is used here to focus purely on the trend over time.

Transformations: The date_time field was parsed into timestamps and filtered to U.S. reports, then aggregated by year.


Plot 2 — Interactive Scatter by Year & Shape (U.S.)

What: Latitude and longitude positions of UFO sightings in the United States. Circle size represents duration, and color encodes the UFO shape.

Encodings: x = longitude, y = latitude, size = duration (capped), color = shape.

Color Map: Different UFO shapes are represented with distinct colors to help distinguish visual patterns.

Transformations: The dataset was filtered to U.S. records, duration values were capped to avoid distortion, and timestamps were parsed.

Interactivity: A year slider allows users to explore sightings across different years. Hover tooltips show details, helping users identify spatial-temporal patterns.