  We report velocity-resolved spectroscopy of infrared hydrogen recombination
lines in the interacting region of the Antennae galaxies (NGC 4038/4039). It
generally has been assumed that the active star formation found there is due to
the interaction of the disks of the two galaxies and indeed two molecular cloud
complexes, separated in velocity by $\sim$100 km s$^{-1}$, have been observed
in the southern part of this region. Our measurements imply that the two cloud
complexes are moving away from each other. This result poses interesting
questions about the physical mechanisms leading to starbursts in Arp 244 and
other interacting galaxies.
