Earth Day and Google Logos

Earth Day (22 April) is one of the Google regular days that its logo has changed. To commemorate holidays and events, Google has put logos designed for those days.

Well, who has designed them? Professional designer who occasionally employed by Google, from public subscription or someone who works full time for Google?

The logos are created by Dennis Hwang who is a webmaster of Google and also designs Google special logos, but the work for logos is only 20% job of him.

By the way, I'm so proud of his last name that is the same with my one, Hwang, very unusual Korean name.