What is a blue moon? What’s the difference between a donkey and a mule? When does the Central Library open on Saturdays?

The Seattle Public Library can now answer all these questions and more via cell phone text.

The library has joined more than 70 libraries from across the United States in providing the text reference service My InfoQuest.

To use My InfoQuest, type a text message with the code SEA and your question (up to 160 characters) and send to 309.222.7740. A librarian will text back a response in minutes.

Answers will be brief (320 characters or less). Answers exceeding 160 characters will be sent in two messages.

The library service is free of charge, but standard text messaging rates may apply depending on phone service provider.

Current hours of service are Monday through Friday from 6 a.m. to 8 p.m., Saturday from 7 a.m. to 4 p.m. and Sunday from 10 a.m. to 4 p.m.

“Text a Librarian gives us another convenient way to provide service to the public,” librarian Toby Thomas said in a press release.

Library patrons already can get their questions answered by email, Web chat, telephone and in person.

My InfoQuest is the first collaborative text message reference service of its kind. The service was developed through a partnership of the Alliance Library System in Peoria, Ill., Altarama Information Systems and Web Clarity Software Inc., the developers of PeopleWhere.

For more information, call the Seattle Public Library at 206.386.4636.