Merge pull request #2049 from walkerdb/next

add aurora binary sensor docs

source/_components/binary_sensor.aurora.markdown

@@ -0,0 +1,35 @@
+---
+layout: page
+title: "Aurora sensor"
+description: "Know when auroras might be visible at your location"
+date: 2017-02-14 10:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+ha_category: Binary Sensor
+ha_release: 0.39
+---
+The `aurora` platform uses the [NOAA aurora forecast](http://www.swpc.noaa.gov/products/aurora-30-minute-forecast) service to let you know if an aurora might be visible at your home location in the next 30 minutes, based off of current solar flare activity.
+
+This service gives a number 0-100 representing the current likelihood of visible auroras at your latitude/longitude. By default this sensor is set up to trigger when the reported likelihood for your location is > 75. It updates every 5 minutes.
+
+You can check the attributes of the sensor to see your exact forecast.
+
+To add the aurora binary sensor to your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+binary_sensor:
+  - platform: aurora
+```
+
+#### Configuration variables:
+
+- **forecast_threshold** (*Optional*): Provide your own threshold number above which the sensor will trigger. Defaults to 75.
+
+```yaml
+  binary_sensor:
+    - platform: aurora
+      forecast_threshold: 50
+```