WMAP
esiegel | March 27, 2013"The radiation left over from the Big Bang is the same as that in your microwave oven but very much less powerful. It would heat your pizza only to -271.3°C, not much good for defrosting the pizza, let alone cooking it." -Stephen Hawking
One of the most powerful predictions of the Big Bang -- the fact that our cold, star-and-galaxy-rich, slowly-expanding Universe came from a hot, dense, much more homogeneous state -- was the existence of a bath of leftover radiation that should be detectable, even today.
Image credit: Pearson / Addison Wesley, retrieved from Jill Bechtold.
Back when the…
esiegel | March 20, 2013"Scientific discovery and scientific knowledge have been achieved only by those who have gone in pursuit of it without any practical purpose whatsoever in view." -Max Planck
Tomorrow morning, at 8 AM my time, the press conference that cosmologists have spent the past decade waiting for will finally happen, and the Planck satellite -- the most powerful satellite ever to measure the leftover radiation from the Big Bang -- will finally unveil its results about the origin and composition of the Universe.
Image credit: ESA / LFI and HFI Consortia.
They've figured out how to subtract the…
catdynamics | May 5, 2010The verdict is out, the 2010 Senior Review Committee recommendation on the NASA Astrophysics old active missions; who will keep going, and who is recommended to get the chop.
It is an interesting list, with some interesting recommendations.
And the winners are...:
1. Planck - level funding for 30 months, per request, consider 42 month extension later
2. Chandra - extend to 2012 and beyond, restore and augment funding, consider automated operation, concern about spacecraft degradation
3. Warm Spitzer - surprise winner! recommend $7M augmentation for 2012 and 2013, note spacecraft ends…
esiegel | May 20, 2008Some of you who've been following astronomy for awhile might remember this report, where a group of astronomers reported finding a giant "void" in the Universe.
What is a void? Well, galaxies are distributed pretty randomly, but because of gravity, they cluster together. A small example is our local group which looks like this,
and a larger example is the Virgo cluster, which is about 1,000 times as massive as our local group, and looks like this:
Well, a void is the opposite of a cluster, where you have a large volume of space that's simply empty of galaxies and matter. This press release…
esiegel | April 3, 2008Two summers ago, I was in Les Houches, France, for a summer school that turned out to be one of the best experiences of my life. Seriously, we'd wake up every day and this was the view from the school:
Well, the University/Institution that ran the school sends periodic updates to me. And they linked me to this release. Here's the interesting and (if it's true) sensational claim that the release makes:
Recently, a team of theorists ... performed a new analysis of all available CMB and LSS data including the WMAP and Sloan data and favor an inflation model where exist primordial gravitational…
esiegel | March 6, 2008The cosmic microwave background is the radiation left over from the big bang. It's very uniform, 2.725 Kelvin everywhere. We're moving with respect to it, so there's a doppler shift, and we see that as a dipole moment in the Temperature. When we subtract that out, we see variations on the order of 30 microKelvins! WMAP is a satellite (Wilkinson Microwave Anisotropy Probe) that measured these anisotropies, and they just released its year 5 data. First off, with the uniform and dipole parts subtracted out, and with the foreground from the galaxy also taken out, here's the map of the microwave…