http://notawoodwind.livejournal.com/ (![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png)
notawoodwind.livejournal.com) wrote in ![[community profile]](https://www.dreamwidth.org/img/silk/identity/community.png)
fandomhigh2011-05-20 08:10 am
notawoodwind.livejournal.com) wrote in fandomhigh2011-05-20 08:10 am
Entry tags:
Advanced Astrophysics (and Arts & Crafts), Friday, 3rd Period - 5/20
Class today featured a large assortment of tubes of glitter in different shades, sturdy paper and glue waiting for the students when they arrived. Because glitter art would never stop being amazing, right kids? Right? Oh, just go with it because Reed wasn't very good at that part of it, okay?
"Good morning, class!" he said cheerfully, passing out the materials before starting on his lecture. And trying not to get glitter on himself. Somehow he was almost sure he'd never live that down if anyone back home caught wind of it. "Today, we'll be discussing dark matter. What we can see or detect around us is only a fraction of the matter in our universe. Far more of it is something that we're only made aware of by the affect it has on the gravity of the visible matter around it."
"While we are unsure just what this so called dark matter is comprised of because there has yet to be a device about to truly study it--" Get to work, Reed! "--there are ideas of just what they might be."
Writing on the board, Reed continued, "It could consist of already existing matter within the universe that we're aware of..."
Brown dwarfs -- These large objects formed in the same way as stars but never accumulated enough gas and dust to reach the critical mass to start hydrogen fusion. Brown dwarfs are about 5 percent of the sun's mass, i.e. usually larger than a planet, but not as large as a star. Astronomers call these and similar objects MACHOs, which stands for Massive Compact Halo Objects. MACHOs can be detected by gravitational lensing. Astronomers think that brown dwarfs are not numerous enough to account for dark matter in the galaxy.
White Dwarfs -- These are the remnants of the cores of dead small to medium-size stars. Although large numbers of white dwarfs exist, there are not enough to account for dark matter (there should be large amounts of leftover helium from them, but this has not been observed).
Neutron stars/black holes -- These are the last remnants of the cores of large stars after supernovae explosions. While they do have large gravitational effects and are invisible because they can even prevent light from escaping (black holes), they are far too rare to account for dark matter.
"...or, it could be something else entirely. Something we call extraordinary matter. This is matter that consists of subatomic particles that very weakly interact with normal matter. That would probably be why they are referred to as WIMPs." Oh, his grin at that was so horribly nerdy. "Or, Weakly Interacting Massive Particles."
Neutrinos -- Subatomic particles that move near the speed of light, but have little mass. These particles probably make up little dark matter within galaxies because they move fast enough to escape even a galaxy’s pull of gravity. However, they may constitute some dark matter between galaxies. So, it is doubtful that they make up much dark matter.
New subatomic particles -- There could be many of these proposed particles. Many come from the theory of supersymmetry, which doubled the number of particles from the standard model. They move relatively slowly and are relatively cold (i.e. undetectable by infrared and X-ray telescopes). Particle physicists are actively trying to find evidence for these theoretical particles to explain dark matter.
Neutralinos (massive neutrinos) -- hypothetical particles that are similar to neutrinos, but heavier and slower. Although they have not been discovered, they are a leading candidate for extraordinary dark matter.
Axions -- small, neutral, low-mass (less than a millionth of an electron) particles
Photino -- similar to photons, but have a mass that is 10 to 100 times greater than a proton. Photinos are uncharged and interact weakly with matter.
Wow, weren't you all glad you took this class now?
Reed smiled again, trying to encourage the kids along. "Now, next week we will be doing pottery, so please wear something you won't mind getting dirty."
"Good morning, class!" he said cheerfully, passing out the materials before starting on his lecture. And trying not to get glitter on himself. Somehow he was almost sure he'd never live that down if anyone back home caught wind of it. "Today, we'll be discussing dark matter. What we can see or detect around us is only a fraction of the matter in our universe. Far more of it is something that we're only made aware of by the affect it has on the gravity of the visible matter around it."
"While we are unsure just what this so called dark matter is comprised of because there has yet to be a device about to truly study it--" Get to work, Reed! "--there are ideas of just what they might be."
Writing on the board, Reed continued, "It could consist of already existing matter within the universe that we're aware of..."
Brown dwarfs -- These large objects formed in the same way as stars but never accumulated enough gas and dust to reach the critical mass to start hydrogen fusion. Brown dwarfs are about 5 percent of the sun's mass, i.e. usually larger than a planet, but not as large as a star. Astronomers call these and similar objects MACHOs, which stands for Massive Compact Halo Objects. MACHOs can be detected by gravitational lensing. Astronomers think that brown dwarfs are not numerous enough to account for dark matter in the galaxy.
White Dwarfs -- These are the remnants of the cores of dead small to medium-size stars. Although large numbers of white dwarfs exist, there are not enough to account for dark matter (there should be large amounts of leftover helium from them, but this has not been observed).
Neutron stars/black holes -- These are the last remnants of the cores of large stars after supernovae explosions. While they do have large gravitational effects and are invisible because they can even prevent light from escaping (black holes), they are far too rare to account for dark matter.
"...or, it could be something else entirely. Something we call extraordinary matter. This is matter that consists of subatomic particles that very weakly interact with normal matter. That would probably be why they are referred to as WIMPs." Oh, his grin at that was so horribly nerdy. "Or, Weakly Interacting Massive Particles."
Neutrinos -- Subatomic particles that move near the speed of light, but have little mass. These particles probably make up little dark matter within galaxies because they move fast enough to escape even a galaxy’s pull of gravity. However, they may constitute some dark matter between galaxies. So, it is doubtful that they make up much dark matter.
New subatomic particles -- There could be many of these proposed particles. Many come from the theory of supersymmetry, which doubled the number of particles from the standard model. They move relatively slowly and are relatively cold (i.e. undetectable by infrared and X-ray telescopes). Particle physicists are actively trying to find evidence for these theoretical particles to explain dark matter.
Neutralinos (massive neutrinos) -- hypothetical particles that are similar to neutrinos, but heavier and slower. Although they have not been discovered, they are a leading candidate for extraordinary dark matter.
Axions -- small, neutral, low-mass (less than a millionth of an electron) particles
Photino -- similar to photons, but have a mass that is 10 to 100 times greater than a proton. Photinos are uncharged and interact weakly with matter.
Wow, weren't you all glad you took this class now?
Reed smiled again, trying to encourage the kids along. "Now, next week we will be doing pottery, so please wear something you won't mind getting dirty."
Listen to the Lecture
Re: Listen to the Lecture
Re: Listen to the Lecture
Re: Listen to the Lecture
Remember the knots that he'd tied his hands into last week while doing the god's eye? Yeah. He wasn't doing much better today. His clothing was going to be twinkling for a month.
Somebody had only signed up for the astrophysics part of this course, yes.
Re: Listen to the Lecture
Re: Listen to the Lecture
These were the biggest, saddest eyes that you had ever seen, Scully. Honest to goodness.
"I'm really, really no good at these craft things..."
Re: Listen to the Lecture
Re: Listen to the Lecture
Because astrophysics was engaging, okay?
Re: Listen to the Lecture
Sure. That's a theory.
Re: Listen to the Lecture
This was not going to stop him from reaching for the paper, however.
Re: Listen to the Lecture
The other half was sixteen and was, against all odds, saying, I want one!
Re: Listen to the Lecture
Jim frowned thougtfully, and then used the glue to trace the outline of what essentially looked like a surfboard, with a sail, and a jet propulsion system built on the back end of it.
"The person riding it steers it, see?"
And now, added to the glue board, a very simple-looking stick figure, standing atop the board.
Re: Listen to the Lecture
Re: Listen to the Lecture
Yeah. Jim dressed like a street urchin from the 17th century, and had mastered solar power well enough to be able to fly with it. Take that, Earth.
"I brought mine with me when I came here, actually."
Re: Listen to the Lecture
Re: Listen to the Lecture
His surfer had gotten him a job. So far, it was probably more popular with the ladies than he was.
Re: Listen to the Lecture
A shame she now had glue snaking up her arm with glitter all over it to cut down on any maturity there.
Re: Listen to the Lecture
"Well, there you go." Jim set down the glue and then leaned over to reach for... more glitter. "I'm free to show people the wonder of science pretty much anytime. Except maybe Sundays. I work Sundays."
Re: Listen to the Lecture
Re: Listen to the Lecture
Re: Listen to the Lecture
Re: Listen to the Lecture
He probably wasn't going to let her go up on the thing alone if, say, she was likely to plummet to her doom.
Re: Listen to the Lecture
Re: Listen to the Lecture
And now he had a glittery chin, to go with the glittery rest of him. He was on a roll today.
"We can go up on it together first, if you're interested. Just so you get a feel for how it rides."
Re: Listen to the Lecture
"Uh-hunh. That would definitely be helpful," she said, keeping her face straight. The glitter didn't help the grin. "And be prepared for a dozen technical questions too."
Re: Listen to the Lecture
"I don't know how technical the answers are going to be, considering I built it out of scrap, and all, but if it comes down to it, I could probably open it up and show you some of the wiring, at least."
Re: Listen to the Lecture