The simplest monosaccharide, glycolaldehyde (CH2OHCHO), has recently been d
etected toward the Galactic center in the source Sgr B2(N) at five frequenc
ies from 71-104 GHz. None of the individual lines used in the detection had
been measured previously in the laboratory; rather, their frequencies were
predicted based on lower frequency measurements. We have now recorded and
analyzed many new rotational transitions of glycolaldehyde through 354 GHz
using two spectrometers. Lines through 48 GHz in frequency were measured wi
th a spectrometer that uses Stark modulation, while the higher frequency tr
ansitions were measured with a FASSST (Fast Scan Submillimeter Spectroscopi
c Technique) apparatus. Analysis of the data has allowed us to confirm the
interstellar identifications and to predict the frequencies of many additio
nal lines not measured in the laboratory.