Starburst Galaxy M94

What could cause the center of M94 to be so bright? Spiral galaxy M94 has a ring of newly formed stars surrounding its nucleus, giving it not only an unusual appearance but also a strong interior glow. A leading progenitor hypothesis holds that an elongated knot of stars known as a bar rotates in M94 and has generated a burst of star formation in the inner ring. Recent observations have revealed the outer, fainter ring is not closed and relatively complex. M94, pictured here, spans about 30,000 light years, lies about 15 million light years away, and can be seen with a small telescope toward the constellation of the Hunting Dogs (Canes Venatici). 

Leonardo Orazi

TRUJILLO et al. 2009 The Astrophysical Journal 704 618

Galaxy HDF850.1 can be seen as it was 12.5 billion years ago

An international team of astronomers led by Fabian Walter of the Max Planck Institute for Astronomy has managed for the first time to determine the distance of the galaxy HDF850.1, well-known among astronomers as being one of the most productive star-forming galaxies in the observable universe. The galaxy is at a distance of 12.5 billion light years. Hence, we see it as it was 12.5 billion years ago, when the universe was less than 10% of its current age. Even more of a surprise, HDF850.1 turns out to be part of a group of around a dozen protogalaxies that formed within the first billion years of cosmic history – only one of two such primordial clusters known to date. The work is being published in the journal Nature.

View of the Northern target area for the "Great Observatories Origins Deep Survey" (GOODS-N). The position of the Hubble Deep Field and, within that field, the position of the submillimeter galaxy HDF850.1, are shown separately. HDF850.1 is invisible for observations using ordinary, visible light. Credit: GOODS-N, STScI / NASA, F. Walter (MPIA)