Archives for April, 2008
Telescopes 100 Years Ago: A Story
Posted by Ethan on April 16, 2008 I was doing a little research into the history of telescopes, and it was about a century ago that they finally realized how much more potential light-gathering power reflecting telescopes had as compared to the older refracting telescopes. On Mt. Wilson in California, astronomer George Ellery Hale and optician George Willis Ritchey (back then everybody…
Dark Matter: Anything Practical About It?
Posted by Ethan on April 15, 2008 Yesterday, my good friend (and SWAB reader) Brian wrote a great comment about the practical reasons to explore space, where he talked about the overall economic impact that Space Exploration has had on the economy, as well as the impact it has had on our knowledge and understanding of the Earth, its environment, and how…
Future News: DAMA discovers Dark Matter?!
Posted by Ethan on April 14, 2008 The DAMA collaboration, an experimental team searching for dark matter via direct detection, is poised to report this week that they have discovered Dark Matter. And I’m here to pre-empt that by bringing you the truth: no, they haven’t. They take some very cold (cryogenic) atoms, look for nuclear recoils resulting from dark matter collisions,…
Q & A: On String Theory
Posted by Ethan on April 14, 2008 Over the past few months, I have been asked a number of questions about String Theory and the Universe, including from readers Benhead and Mastery Mistery. But now Jamie, whom I’m going to marry later this year, has been asking me about it, and so it’s time to write something about the scientific topic of…
Weekend Diversion: Ninja Warrior!
Posted by Ethan on April 12, 2008 Nothing to do with astronomy or physics (except for the perils of gravity), but this TV show is hilarious: Ninja Warrior. I don’t get the channel G4 here in Tucson with expanded cable, but this is basically the Japanese version of the American Gladiators event: The Eliminator! If you have some time to waste, watch…
Why Explore Space/the Universe?
Posted by Ethan on April 11, 2008 Fraser Cain over at Universe Today sent out a question to the Astronomy/Astrophysics/Space communication community today. And he asks: Why should we spend our time/money/resources on exploring space when there are so many problems here on Earth? This is something that, for better or worse, I had a knee-jerk reaction to. Here’s what I wrote…
Energy Conservation and an Expanding Universe
Posted by Ethan on April 11, 2008 So, what’s the deal with this one? startswithabang.com reader Scott Stuart asks the following question: I was reading “The First Three Minutes” last night and came across an interesting section about blackbody radiation and energy density. The author states that as the universe expands, the number of photons running around (in the CMB, for example)…
Video Killed the Radio Star!
Posted by Ethan on April 10, 2008 In my mind, and in my car, we can’t rewind, we’ve gone too far, pictures came and broke your heart, put the blame on VTR. And for those of you who are under the age of 25, VTR stands for Video Tape Recorder. This was the Buggles, who made the first music video that ever…
Is Dark Energy the same as Acceleration?
Posted by Ethan on April 10, 2008 In a comment on my last post, What is Dark Energy, Kendall asks the following, which is such a good one I think it deserves its own post: I thought the expansion was accelerating? Aren’t you saying that it is on its way down to 85% of its current rate? Sounds like expansion is slowing,…
What is Dark Energy?
Posted by Ethan on April 9, 2008 You’ve all heard these words before. Dark Energy. But what is it, and why are we stuck with it? Let me start by telling you a story. Imagine, for a minute, that you have a candle. You know everything about this candle, including how bright it is and how far away it is from you.…
