WASHINGTON -- Family and invited guests are gathering at Arlington National Cemetery to say their final goodbyes to astronaut and Sen. John Glenn.

Glenn, the first American to orbit Earth, died Dec. 8 at age 95.

Watch video of the ceremony:

He was mourned and celebrated at public events in home state Ohio at the time, but those close to the family say Thursday's interment is closed to public and news media so his wife and children have the chance for a more personal memorial.

In Glenn's honor, flags of federal entities and institutions will fly at half-staff.

A private chapel service began at 9 a.m. followed by a procession to the graveside by caisson, a flyover, a graveside service and taps.