Star Stryder

Archive for the 'Cosmology' Category

Feb 14th, 2008
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Do we really need Dark Matter and Dark Energy?

I’m still here, but it’s an exam week, so I bring you another guest blogger, Ethan Siegel, who knows way more about dark matter than I probably ever will (a theorist even!). Enjoy his guest post!
This is Ethan from Starts With A Bang! over here at Pamela’s blog, Star Stryder. I was pretty pleased […]

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Jan 30th, 2008
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Dark Energy is Real

This is apparently the post I wasn’t supposed to publish. I wrote it yesterday, and had it somehow utterly disappear from my HD after a crash. I then was writing it in wordpress and had Firefox crash on it before the first auto save…
In a really cool press release that I got yesterday but couldn’t […]

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Nov 28th, 2007
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1 Void a 2nd Universe Makes?

Ok, so New Scientist is just not making my brain happy this week. I decided to forage around their website  to see what was there (one of their editors, Maggie McKee, is a friendly soul I worked with at Astronomy and I wanted to see what’s she’s up to now a days). While Maggie has […]

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Nov 26th, 2007
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I see you, now you must die

The title is a summary of how a New Scientist article seems to interpret the fate of the universe. Basically, the article states that because we view the universe, we may be causing the collapse of wave functions that would otherwise be happily balanced between not alive and not dead (the Schrondinger’s litter of supernovae, […]

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Oct 24th, 2007
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The Improbable Universe

Slide Show + Audio (.mp4)
Transcript: This is a talk I originally prepared to present as part of the 2206-2007 convocation series at Illinois College. Since then I have given it before several other audiences, and with every presentation I’ve had more people ask, will this be online. Finally, I can saw yes. Here’s the link. […]

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Oct 3rd, 2007
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Type 1a Supernoave: A Non-Standard Candle

One of the most exciting discoveries of astronomy in recent years was the measurement of an acceleration term in the universe’s rate of expansion. Announced by both the Supernova Cosmology Project at the Lawrence Berkeley National Laboratory and the High-z Supernova Search Team, these results at once confirmed one another an revolutionized how astronomers view […]

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Aug 23rd, 2007
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Mostly Empty Space

When we look at the cosmic microwave background we see both overly warm and overly cold spots. The warm spots grew into places with a lot of stuff; namely our modern galaxies. The cold spots grew into places without a lot of stuff; these are cosmic voids. While we have known for a long time […]

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May 12th, 2007
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And it came from the CMB . . .

wmap_skymap.jpgFraser (my co-host over at Astronomy Cast) and I like to joke about how everything we know in astronomy we know because of the Cosmic Microwave Background. How do we know the universe formed during the Big Bang? The CMB. How do we know the cosmic geometry is flat? The CMB. How do we know the mass distribution of the Oort Cloud? The CMB. How do we know where babies come from? The CMB.

Okay, so that last one is an exaggeration. As far as I know, human babies and the CMB have nothing in common. The remark about the Oort Cloud, however, may not always be as far fetched as it sounds. A group of scientists working at the Harvard-Smithsonian Center for Astrophysics, and lead by David Babich, have theorized a new technique for determining the mass distribution in the Oort cloud using distortions in the Cosmic Microwave Background.

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