<RadioButtonGroup name="shipSpeed" defaultSelected="not_light">
<RadioButton
  value="light"
  label="prepare for light speed"
  style={{marginBottom:16}} />
<RadioButton
  value="not_light"
  label="light speed too slow"
  style={{marginBottom:16}}/>
<RadioButton
  value="ludicrous"
  label="go to ludicrous speed"
  style={{marginBottom:16}}
  disabled={true}/>
</RadioButtonGroup>
