POPPING BROCCOLI!: Imagine our surprise and delight this morning when we checked our countertop garden and found a couple of broccoli seeds had already sprouted. That was quick! We just planted them on Tuesday.
By this afternoon, multiple broccoli plants had poked through the soil. Excellent. It will be fun to watch and see what comes up next.
LOVIN' IT: On our way out the door to the kids' programming class today, CJ pronounced it his favorite of the classes he's taking it right now. "It's one place to let your imagination break free of the
chains of your mind," says CeeJ. :)
YES WE CAN! When I logged onto Facebook this morning, about the first thing I saw was a post from Col. Chris Hadfield onboard the ISS. He posed a question to readers: "Attention physicists - we've been traveling 8 km/sec for 5
months. How much has our time relativity differed from everyone else?"
I called the kids over to the computer to show the Col. Hadfield's question. They both recognized it as exactly the type of scenarios we've been going over this week in our Stanford via Coursera class about Einstein's special theory of relativity.
In fact, as regular readers might recall, just two days ago I posted this equation, the Lorentz factor ...
Well guess what? That's exactly what we needed to figure out the answer to Col. Hadfield's question.
It was fun reading all the answers/comments on the thread. "That's cool! We know all that stuff!" Annabelle said as she read people debating how to figure it out.
Later, Hadfield posted, "The
correct answer (for those still calculating): gamma = 1/sqrt(1 - v^2/c^2) (v =
8km/s, and c = the speed of light/300,000). t = t_0/gamma (t_0 = 5 months). dt = t_0 - (t_0/gamma) = 0.0046s"
In other words, Hadfield has 'gained' .0046 of one second on us during his 5 months in low Earth orbit (or, he has traveled into the future 0.0046 seconds, and to the "future us" he's 0.0046 secs younger).
As one commentor pointed out, "He's asking how much time dilation
he has experienced due to his high velocity. Objects moving at close to the
speed of light experience less time than objects at rest, relative to one
another. The Col. Is moving
at 0.0026% of the speed of light, so the time dilation is very small, but he
has literally experienced less time than we have on earth. For more info just
search for "time dilation". There are simple explanations involving
trains and bouncing balls and whatnot. It's not actually too complicated. The
answer I got was 4.6 milliseconds."
As we read that we were nodding our heads in agreement. And to think that just a week ago, we wouldn't have understood hardly any of it. What a different a week makes (thank you Coursera and Professor Larry Randles Langerstrom!).
RESERVOIR DOGS: This afternoon, the kids participated in a yoga demonstration class for their longtime yoga teacher who was training other teachers. For the session, we drove down to Columbia City in Rainier Valley.
It was beautiful out today and I told the kids if we left early, we could hit a park or two in that part of town, where we haven't been for months, if not a year plus.
We spent about an hour at sprawling Jefferson Park.
It's a real gem, formerly land off limits but now it's a fantastic gathering place situated atop a water reservoir. It affords lovely views of Seattle and the bay from the southeast perspective.
One thing that sets this park apart from any other we've ever been in are the great little plaques embedded in the ground 'round its 45 acres. For instance this medallion lets people know about the water underfoot.
As does this ...
The kids became a part of the sculpture (note the teeny little Space Needle just west of CJ's, um, posterior).
Of course, there is a playground, too. Here, CJ & Annabelle enjoy a Class-1 lever.
FLYING HIGH: Several times today, we checked in on Solar Impulse, a first-of-its kind solar powered plane.
It took off from California this morning at 6:12 a.m. After class and errands this a.m., we checked in with it a little after 2 p.m. Right then, it was approaching NASA's Dryden Flight Research Center at Edwards Air Force Base.
Solar Impulse was flying at a rate of 26 knots (or 29.9 miles per hour), at 100 percent battery status, 37 percent engine power, 49 percent solar generator power, ground speed is 48 knots, with an altitude of 21742. The temperature up there was -13 degrees Celsius, or 8.6 degrees Fahrenheit.
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