Archives for June, 2009

First light is one of the most important tests of any new telescope. It allows you to look at a well-known object, see if there are any problems with your telescope, and to get a small glimpse of how good your telescope is going to be. Almost 20 years ago, we launched the Hubble Space…

By 1948, our view of the Universe had changed drastically from 1909. Instead of space being run by Newton’s Gravity, where our Milky Way comprised the entire Universe, we had learned that space and time are governed by Einstein’s General Relativity, that our Universe contained at least many thousands of other galaxies, and that the…

There are many great discoveries that happened in the 1930s that changed our view of the Universe. From tiny discoveries (the neutron) to huge ones (Pluto), from theoretical explanations of antimatter to the neutrino to the start of quantum field theory, the 1930s were a great time for making new discoveries. But one man often…

We’ve got a lot going on here in America these days, with towering unemployment, a dying manufacturing industry, huge environmental problems, and the tense fight for all sorts of rights and freedoms, such as GLBT equality and abortion rights. But there are two things that I’d like to remind you of this weekend. First off,…

Amazing is an understatement when it comes to how much we’ve learned about our Universe in the last century. 90 years ago we confirmed general relativity, and got a whole new theory of gravity as a result. But, we still thought our Milky Way was the only galaxy in the Universe. There were a few…

100 years ago, the way we viewed our Universe was vastly different than the way we view it now. The night sky, with stars, planets, comets, asteroids, nebulae, and the Milky Way, was viewed to make up the entire contents of the Universe. The Universe was static, governed by two laws only: Newton’s Gravity and…

What’s the Point?

This week at work, we’re interviewing candidates for the job that I’m leaving. And one of the questions that came up was so simple and so fundamental to all that we do here that I thought I would ask it to you: With all the problems in the world — economic, political, social, and military…

A Free-fall Follow-up

One of the toughest things to do in science is to figure out — of all the things that exist in the world — is which ones are relevant to your problem. Take the Leaning Tower of Pisa, for instance. Specifically, I wrote about Galileo’s famous problem, where you take two cannonballs, one that’s 10…

One of the simplest tricks you can use physics for is to figure out how high up you are. Either using a stopwatch or just by counting seconds, drop a dense object (e.g., not paper, a tissue, etc.) and figure out how long (in seconds) it takes from when you release the object to when…

Weekend Diversion: On the Road Again!

Nothing too crazy this weekend, folks. Why not? Believe it or not, because for the past 7 days, I’ve been on a road trip! We’ve been through Oregon, Washington, Idaho, Montana, North Dakota, Michigan, and Wisconsin, and we’re now headed back through Iowa, South Dakota, and possibly Wyoming. The weather is gorgeous, the landscapes, skies,…