RESUMO
We present 1.3 cm and 2 cm subarcsecond resolution VLA images of the dwarf galaxy NGC 5253. Within the central starburst, we detect high-brightness [Tb&parl0;2 cm&parr0; approximately 100-12,000 K] radio continuum sources. These appear to be very dense, "compact" H ii regions. The dominant radio source is a nebula approximately 1-2 pc in size, requiring several thousand O stars within the volume to maintain its ionization. This nebula has no obvious optical counterpart. The number of ionizing photons we find for this cluster is nearly 2 orders of magnitude larger than indicated by Halpha fluxes, and the deduced stellar content accounts for a significant fraction of the total infrared luminosity of the galaxy. This cluster is a strong candidate for a globular cluster in the process of formation, perhaps the youngest globular cluster known.
RESUMO
We report VLA detections at 1.3, 2, and 3.6 cm of the Egg Nebula, RAFGL 2688. We resolve the source and find an inner 9&arcsec; diameter core that is produced by approximately 0.01 M middle dot in circle of dust. It seems that the Egg Nebula experienced a major mass ejection, losing approximately 1 M middle dot in circle during the past =1200 yr. The centimeter-wavelength emission is extended at a position angle of 53 degrees, while the famous jets and lobes in the Egg Nebula lie along a position angle of 15 degrees. The multiple symmetries in the Egg Nebula may occur because the rotation axis of the mass-losing star is not perpendicular to the orbital plane of the putative close binary. Between 3.6 cm and 350 µm, the dust opacity appears to vary as nu0.6, which can be explained if there are some grains with sizes at least as large as 0.5 cm.