U.S. state capitals overlayed on a map of the U.S

{
  "$schema": "https://vega.github.io/schema/vega-lite/v2.1.json",
  "width": 800,
  "height": 500,
  "projection": {
    "type": "albersUsa"
  },
  "layer": [
    {
      "data": {
        "url": "data/us-10m.json",
        "format": {
          "type": "topojson",
          "feature": "states"
        }
      },
      "mark": {
        "type": "geoshape",
        "fill": "lightgray",
        "stroke": "white"
      }
    },
    {
      "data": {
        "url": "data/us-state-capitals.json"
      },
      "encoding": {
        "longitude": {
          "field": "lon",
          "type": "quantitative"
        },
        "latitude": {
          "field": "lat",
          "type": "quantitative"
        }
      },
      "layer": [{
        "mark": {
          "type": "circle",
          "color": "orange"
        }
      }, {
        "mark": {
          "type": "text",
          "dy": -6
        },
        "encoding": {
          "text": {"field": "city", "type": "nominal"}
        }
      }]
    }
  ]
}