More on Space and Time

Innocent me (stop laughing, Kev) decided to read an article on Hubble (“Is Hubble Worth the Upgrade Mission’s Risk and Cost?“) over on LiveScience. There’s a bunch of links down at the bottom of the article (below the poll) and one of them linked to a Science.com article “Why the Universe is All History” which deals with the light/time issue that I brought up earlier.

This article discusses the issue well, although it still hurt some to read it then try to grasp the concepts. The first bit of the article is what caused a big AHA! moment for me. I bolded the section that I like the most.

It took 300 years of experiment and calculation to pin down the speed at which light travels in a vacuum: an impressive 186,282 miles per second.

Light will travel slightly slower than this through air, and some wild experiments have actually slowed light to a crawl and seemingly made it go backward, but at the scales encountered in our everyday lives, light is so fast that we perceive our surroundings in real time.

Look up into the night sky and this illusion begins to falter.

Cool. So because the light here is slower (in galactic terms) what we see right now is in real time. The article continues by saying the moon’s (reflected) light is 1.2 seconds old when we see it. When we look at the closest star system (Proxima Centauri), the light from it that we perceive is 4 years old.

Where I went lost earlier is that in bringing Proxima Centauri closer via the telescope, we aren’t necessarily looking at its 3 yr old light vs the 4. The “age” of the light hasn’t changed because we’ve not moved. The telescope lens only brings that perceived light into better focus. No matter how big a telescope we make, we’ll only ever see 4 yr old light from that star system.

What is happening with bigger telescopes–and the telescopes in space–we are seeing further away and therefore, seeing further back into time. We can now see galaxies that are so far away, their light is billions of years old. We’ve not moved toward it, only been able to bring space into better focus. And that focus is getting better and better.

Time in the Dark

Our power went out last night from just before 7pm until nearly midnight. We sat out on the back porch to read and play with the dogs. The normally quiet neighborhood was filled with the sounds of kids (and adults!) playing outdoors. Once it got too dark to see, everyone went inside. We lit some candles (we have a cool lantern but I spilled fuel everywhere so we didn’t light it) and sat in the living room, listening to the silence.

And silence is loud.

No fish tanks. No whirring laptop fans. No window fan. No refrigerator or freezer motors. Silence.

There was the drip from one of the fish filters. And there was a ticking clock (which promptly was put outside; I can’t stand that sound). There was the wind in the bamboo. The sounds of traffic.

Lorna and I sat and talked about what would the night sounds be in Whitehaven, the fictional town in my Fantasy novel. Families would gather in one room until they went to bed. Unless they were rich, you’d not take a candle to your room and sit with it lit. What would you do? A single candle is very hard to use as light to read. What would the family do? They’d hear doors opening and shutting. They’d hear the occasional loud sounds coming from businesses open after dark, like taverns and maybe from the lobbies of hotels or boarding houses.

When you’d be ready for bed, you’d take your candle up to see your way. And since you’d get up long before the sun came up in order to be ready to start work, you’d bring your candle back down. Where would you keep it? Or would you use a very small lantern?

How would businesses light up their spaces? Lanterns, candles, fireplaces. There’d be someone who sold loads of wood to everyone. Where would you keep it? There’d be the candle maker, the glass maker, the potter – all businesses to support the lighting. Would cook/heating stoves be made in town or made elsewhere and brought in? Would you go to them all individually or would you purchase what you need from a mercantile type of store?

This made me realize I never envisioned a heat source for Sarah’s family shop. They had the cook stove in the kitchen but I didn’t have anything in the shop where they worked. Primarily this never came up in my visualization of the place because she’s not there when it gets cold. But when I describe (via the “show, don’t tell” method, of course) the shop, I never mention the heat source. Would it be necessary to do so?

So we discussed what we’d hear and why. What we’d see and why. And why not for both. It was a quiet talk between us but sadly took up only about 45 mins or so.

The power company called my cell phone at about ten to say it was going to be much later before the power was back on. I drug out the deep cycle battery and hooked up the air pumps for the fish tanks. Didn’t want to get up to a bunch of dead fish.

Then I went to bed. At 10:30. I wasn’t sick, either. I don’t think I’ve gone to bed that early in a very long time. I wanted to stay up and write. But the laptop drains the deep cell battery quickly, especially with the air pumps going at the same time. I laid there, staring out in the darkness, wide freakin’ awake. I did fall asleep several times but woke myself up snoring. My CPAP doesn’t have a battery back up. A little before midnight, the lights came on and I got up to turn everything off, fix the air pumps, etc etc.

And it was very loud in the house again.