A little push at the beginning makes it more interesting.

July 21st, 2010 | Tags: Physics, xkcd | Category: Science | Leave a comment

This lovely image is of our home, the Milky Way galaxy, but in a way our mortal eyes cannot perceive it. It doesn’t show stars, but the stuff that makes (or will make) up stars and planets and whatnot — clouds of gas and dust.

Our eyes can see only a tiny fraction of light — the visible spectrum, ROYGBIV (rainbow colors) — but the universe also glows in other kinds of light: gamma ray, X-ray, ultraviolet, infra-red, microwave and radio. And each frequency tells us something different.

The atmosphere blocks some of those frequencies (fortunately for life in Earth), so to view the universe in this exotic light astronomers have to depend on telescopes out in space. The European Space Agency, for example, launched the Planck Surveyor telescope to capture images in the microwave range, like this one here.

Microwave imaging gives us two important sets of information about the Milky Way and the universe we are in.

First, the huge clouds of gas and dust in the galaxy (which are mostly invisible to our eyes) are what eventually turn into stars and planets (and all the stuff that ends up on planets). In the photo, those clouds are all those wispy bluish-white and pinkish-white tendrils stretching out from the center (the galactic equator).

July 5th, 2010 | Tags: Astronomy, Big Bang, microwave, Planck Surveyor | Category: Astronomy, Physics, Science | Leave a comment

JISHOU, HUNAN — I just read this at Pharyngula. Words escape me.

Any of my former physics students could write a better explanation of electricity than this tripe. It’s apparently from a homeschooling science text peddled by Bob Jones University.

[The link in PZ's post seems to be broken. The page shown is from the Science 4 textbook, printed in 2004.]

July 3rd, 2010 | Tags: education, Science, textbooks | Category: Random rants, Science | Comments (2)

A crewmember aboard the International Space Station caught this view of the aurora australis (the Southern Lights) during a geomagnetic storm last month.

Auroras happen when electrically charged particles from the Sun smack into Earth’s atmosphere and ionize the oxygen and nitrogen there. Since the high speed particles follow the Earth’s magnetic field, they primarily end up over the magnetic poles. B ut, when the Sun is especially active (or when it burps out a solar flare, as it did on May 24), the auroral displays can be seen at lower latitudes.

Ionized gases emit light of particular frequencies — colors. Neon, for example, glows a bright red color. Oxygen in the atmosphere typically emits green light, as we can see in the photo.

June 24th, 2010 | Tags: aurora, NASA.photo, space | Category: Astronomy, Physics, Science | Comments (1)

CHANGSHA, CHINA — Unlike my last trip to the vicinity of Changsha, this one was not fraught with peril. The disasters were limited to the movies I watched.

Our bus screened two mega-disaster movies, the American 2012 and the Thai copycat version 2022: The Great Tsunami. (It goes without saying both were pirated copies.) And, before I fell asleep in my hotel Saturday night, I watched that classic star-studded extravaganza, The Towering Inferno, with dialogue dubbed into Chinese, of course.

Disaster movies are just really stupid, you know? It makes no difference when or where they are made. They’re just mindless entertainment.

Let’s start with Roland Emmerich’s 2012. As soon as heard the Important Scientist announce ominously that a massive solar flare had sent a storm of neutrinos toward Earth, and these neutrinos for the first time ever (Now with new cleaning power!) were interacting with matter, I knew the rest of the movie would be, scientifically, a stinker.

I was not disappointed.

Physics mini-lesson: Yes, the Sun produces neutrinos. Lots of neutrinos. They are a product of nuclear fusion, the gift that keeps on giving us heat and light from that yellow ball in the sky. The sun has been pumping out these little fellows for the last five billion years, and like all other subatomic particles, solar neutrinos don’t suddenly take the notion to change their ways. Neutrinos normally sail right through the Earth (and us, by the way) like nothing is there. They only very rarely interact with atoms, detectable by little flashes of light in huge underground tanks of pure water.

December 15th, 2009 | Tags: 2012, 2022, apocalypse, disaster, movies, The Towering Inferno | Category: China, Commentary, Media, Science | Comments Off

Especially air-breathing apparatus and/or a good pressure suit … “Ideal conditions” are not so ideal for living organisms.

December 11th, 2009 | Tags: ideal conditions, Physics, xkcd | Category: Science | Leave a comment