Category Archives: galaxies

Blobs in Spaaaaaace!!

Courtesy Hubble Space Telescope Science Institute
Courtesy Hubble Space Telescope Science Institute

Sometimes images of distant objects in the universe look like out-of-focus paint daubs on black paper. Not terribly interesting visually, but if you know what you’re gazing at, those blobs in space tell a fascinating tale of life in the cosmos less than a billion years after the Big Bang. They may look like shards of light and color, but these objects are now identified as some of the earliest star-forming galaxies in the cosmos.
Now astronomers are debating whether the hottest stars in these early galaxies may have provided enough radiation to “lift a curtain” of cold, primordial hydrogen that cooled after the Big Bang, ushering in the epoch of reionization, a time when the universe became transparent to light. Understanding the role these galaxies played in the EOR is a problem that has perplexed astronomers over the past decade.

The epoch of reionization is thought to have ended 0.5 to one billion years after the Big Bang. Astronomers have been looking for its signature in everything from radio astronomy signals to infrared emissions. The major difficulty in understanding exactly what the story is out there at the end of the first act of galaxy formation. Because the galaxies are so far away, they are very faint and extremely difficult to find. Now Hubble, and very likely other infrared-enabled observatories, along with a scattering of radio telescopes, are pushing the envelope of discover out at dawn of creation.

More Rainy Day Astronomy

the Antennae galaxies
the Antennae galaxies

In an entry a long time ago I talked about what to do when the skies are clouded out from rain, snow, smog, light pollution, or whatever else it is that keeps you from stepping out for some stargazing. Reading books is always a cool thing. Right now I’m making my way through Alan Guth’s “The Inflationary Universe,” wherein he explains the birth of the universe. I got started on that because of a conversation I had with a friend a few weeks back about the incredible occurrence of the creation of the cosmos and how science explains it. So, my current “rainy day” activity (and late nights, and Saturday afternoons) is all Steve’s fault. (Steve, you know who you are.)

But, if you aren’t in the mood for a good book, there’s always Web surfing. As usual, there are a great many really cool Web sites that talk about astronomy and space science. I’ve talked about the The Astronomy Picture of the Day, and of course Phil Plait’s Bad Astronomy Web site with its attached forum discussion area. And of course, I have mentioned the Gemini Observatory web site, which is being revamped before ourvery eyes. These are in addition to the wonderful sites I’ve linked to over in the left column that take you to the European Southern Observatory and the Hubble Space Telescope Science Institute.

So, there’s no shortage of places to go. Just for grins, here are a couple of new ones for you to explore. The first is the Spitzer Space Telescope. Here’s a little taste to whet your appetite for this new observatory’s work.

The other web page is a subset of the Haystack Observatory educational tutorial website, which contains a lovely radio astronomy “short course” you can browse through to learn a little about the fascinating science being done with the world’s radio dishes and networks. Next time you’re stuck indoors, give it a whirl!