As we improve our ability to look back to the early universe, the changes we see in galaxies at this period compared to later eras are striking. A new study, using data from the Hubble Space Telescope's Wide Field Planetary Camera 3 has been gathering infrared imagery back to a period as early as 480 million years after the Big Bang. What stands out in this work is the rate of star formation. In the period between 480 million to 650 million years after the Big Bang, the rate of star birth increased ten times. Garth Illingworth (UC-Santa Cruz) calls the result "...an astonishing increase in such a short period, just 1 percent of the current age of the universe." Moreover, the number of galaxies themselves showed a marked change. Says Illingworth: "We're getting back very close to the first galaxies, which we think formed around 200 to 300 million years after the Big Bang... Our previous searches had found 47 galaxies at somewhat later times when the universe was about 650 million...

Be aware of a NASA teleconference coming up at 1 PM EST (1800 UTC) today to discuss interesting Hubble data re the early universe. I'll be publishing today's entry on these findings not long after the teleconference starts. You can follow audio of the event here.

Next week I'll be reviewing Richard Panek's The 4 Percent Universe (Houghton Mifflin Harcourt, 2011), a penetrating look at our investigations of dark matter and dark energy. But plenty of information has also come out of the American Astronomical Society's 217th meeting, which ended yesterday. We looked at interesting gravitational lensing results in the previous post, pondering how they affected our census of high-redshift galaxies, but equally intriguing is a study of 14 massive galaxies that helps us map out the distribution of dark matter within them. The work was led by David Pooley (Eureka Scientific), focusing on galaxies with strong gravitational lensing characteristics. The 14 galaxies average about 6 billion light years away, and they appear almost directly in front of even more distant galaxies that each include a supermassive black hole at galactic center with associated quasar. You know from our ongoing discussions of the FOCAL mission what to expect -- light from the...

As we continue to investigate the parameters of the proposed FOCAL mission to the Sun's gravitational lens, it's worth recalling how the idea of lensing has taken hold in recent decades. Einstein noted the possibilities of such lensing as far back as 1936, but it wasn't until 1964 that Sydney Liebes (Stanford University) worked out the mathematical theory, explaining how a galaxy between the Earth and an extremely distant object like a quasar could focus the latter's light in ways that should be detectable by astronomers. And it wasn't until 1979 that Von Eshleman (also at Stanford) applied the notion to using the Sun as a focusing object. It was Eshleman who suggested sending a spacecraft to the Sun's gravitational focus at 550 AU for the first time, where magnifications, especially at microwave frequencies like the hydrogen line at 1420 MHz, are potentially enormous. This was a year after the first 'twin quasar' image caused by the gravitational field of a galaxy was identified by...

Yesterday's news conference on the Planck mission, held at the Millimeter and Submillimeter Sky in the Planck Mission Era conference in Paris, was so absorbing that I abandoned previous plans and stayed glued to the monitor most of the afternoon, replaying particular points from the various presenters (although keeping an eye on AAS happenings via Twitter as well). The video is available here, and it's well worth a look given Planck's interesting results so far, and the rich study of the Cosmic Microwave Background that will eventually flow from its data. The European Space Agency has been offering broad coverage of the Planck findings, but before you check these out, bear in mind that the primary mission of the spacecraft is to measure the fluctuations in the CMB that both COBE and, to a higher level of detail, WMAP observed. It was fun to watch the sparring between the assembled Planck team and journalists at the conference when the question of data release came up. We won't have...

With the American Astronomical Society getting ready to convene its 217th meeting in Seattle on the 9th, it seems fitting to talk about one of the most splendid 'nearby' stellar objects, the Andromeda Galaxy, otherwise known as M31. Edwin Hubble was the first astronomer to resolve individual stars in the galaxy, but working with Milton Humason, he did something even more significant, studying Cepheid variable stars inside it whose brightness varies in a regular pattern that indicates their absolute magnitude. These 'standard candles' made it possible to find M31's distance, which Hubble showed was much greater than that of any stars in the Milky Way. We were learning in Hubble's day that the 'spiral nebulae' once thought to be part of our own galaxy were distant 'island universes' in their own right, a vast expansion of the size of the cosmos as humans understood it. M31 is the closest spiral galaxy to ours at roughly 2.5 million light years, offering up a spectacular view of as many...