PORTSMOUTH, N.H. — A York, Maine, man has become the 500th person to fly into space as space shuttle Endeavor lifted off.

Janice Cassidy, mother of the 39-year-old Christopher Cassidy spoke with the Portsmouth Herald via cell phone following the launch Wednesday and said she was “overwhelmed.”

She said she is very proud of her son.

Cassidy is scheduled for three space walks as part of the mission, according to NASA.

Janice Cassidy said the many delays in June and then July were tough on everyone, particularly the crewmembers, who managed to keep their spirits high nonetheless.

The crew will be away for 16 days, during which time Janice Cassidy said she would be able to communicate with her son via e-mail.