Not to ruin anyone's valentines, but that pic and every other space pic of distant galaxies are artificially colorized. They took artistic license to make it look like a rose. It even says so in their press release.
"Previous images of NGC 7129 taken by visible telescopes show a smattering of hazy stars spotted against a luminescent cloud. Spitzer, by sensing the infrared radiation or heat of the cluster, produces a much more detailed snapshot. Highlighted in false colors are the hot dust particles and gases, respectively, which form a nest around the stars. The pink rosebud contains adolescent stars that blew away blankets of hot dust, while the green stem holds newborn stars whose jets torched surrounding gases."