GitHub provides several timeline resources in Atom format. The Feeds API lists all the feeds available to the authenticated user:

• Timeline: The GitHub global public timeline
• User: The public timeline for any user, using URI template
• Current user public: The public timeline for the authenticated user
• Current user: The private timeline for the authenticated user
• Current user actor: The private timeline for activity created by the authenticated user
• Current user organizations: The private timeline for the organizations the authenticated user is a member of.
• Security advisories: A collection of public announcements that provide information about security-related vulnerabilities in software on GitHub.

Note: Private feeds are only returned when authenticating via Basic Auth since current feed URIs use the older, non revocable auth tokens.
Get feeds