Credit: Alberto Bolatto, Univ. Maryland
ALMA carbon monoxide image of outflowing gas in NGC 253. Color represents the brightness of the emission (red is faint, purple is bright). The bright central lane, colored in green to purple, is the densest concentration of molecular gas, associated with the bar in this galaxy. The fainter (red) pillars of emission perpendicular to it correspond to ejected molecular gas. The areas where molecular expanding shells are observed, likely caused by young stellar clusters, are illustrated by stars and arrows to give an idea of the expanding motions. The dashed line illustrates the cone of the hot outflow seen in X-rays.