We have a bumper day today thanks to NASA’s Hubble Space Telescope.

Oldest Galaxies Seen

First up, Hubble has broken the distance limit for galaxies and uncovered a primordial population of compact and ultra-blue galaxies that have never been seen before. The deeper Hubble looks into space, the farther back in time it looks, because light takes billions of years to cross the observable universe. This makes Hubble a powerful “time machine” that allows astronomers to see galaxies as they were 13 billion years ago, just 600 million to 800 million years after the Big Bang.

The deep observations also demonstrate the progressive buildup of galaxies and provide further support for the hierarchical model of galaxy assembly where small objects accrete mass, or merge, to form bigger objects over a smooth and steady but dramatic process of collision and agglomeration. It’s like streams merging into tributaries and then into a bay.

Hubble Pinpoints Distant Galaxies in Deepest View of Universe.

NASA, ESA, G. Illingworth and R. Bouwens (University of California, Santa Cruz), and the HUDF09 Team

"These galaxies are as small as 1/20th the Milky Way’s diameter," reports Pascal Oesch of the Swiss Federal Institute of Technology in Zurich. "Yet they are the very building blocks from which the great galaxies of today, like our own Milky Way, ultimately formed," explains Marcella Carollo, also of the Swiss Federal Institute of Technology in Zurich. Oesch and Carollo are members of Illingworth’s team.

These newly found objects are crucial to understanding the evolutionary link between the birth of the first stars, the formation of the first galaxies, and the sequence of evolutionary events that resulted in the assembly of our Milky Way and the other “mature” elliptical and majestic spiral galaxies in today’s universe.

History of Galaxies in One Image

This is the coolest images I’ve seen in a while: More than 12 billion years of history are shown in full-color view of thousands of galaxies in various stages of assembly. The image was made from mosaics taken in September and October 2009 with the newly installed Wide Field Camera 3 (WFC3) and in 2004 with the Advanced Camera for Surveys (ACS). The view covers a portion of the southern field of a large galaxy census called the Great Observatories Origins Deep Survey (GOODS), a deep-sky study by several observatories to trace the evolution of galaxies. The final image combines a broad range of colors, from the ultraviolet, through visible light, and into the near-infrared. Such a detailed multi-color view of the universe has never before been assembled in such a combination of color, clarity, accuracy, and depth

12 billion years of cosmic history in one panorama.

NASA, ESA, R. Windhorst, S. Cohen, M. Mechtley, and M. Rutkowski (Arizona State University, Tempe), R. O’Connell (University of Virginia), P. McCarthy (Carnegie Observatories), N. Hathi (University of California, Riverside), R. Ryan (University of California, Davis), H. Yan (Ohio State University), and A. Koekemoer (Space Telescope Science Institute)