« Happy Thanksgiving! | Main | Old Enough to Vote »

Sunday, 26 November 2023


Feed You can follow this conversation by subscribing to the comment feed for this post.

"Light, the fastest thing we know of, actually travels kinda slowly."

It's a good thing we have global shutters. Otherwise, the sun would look like a leaning, oval golf ball. I hope I'm understanding that correctly ;)

Laundry is therapeutic to many people. I know a cardiologist who loves doing his family's laundry when not looking at heartbeats.

This Solar System 2.0 is a more realistic model as our solar system moves with time along the Milky Way.

Mike wrote, "We 'look back in time' as we look at stars, so we're looking back 4.25 years in time when we look at Alpha Centauri in the night sky."

I used to "look back in time" by developing and printing last year's Christmas pictures in time to share them with family on the July Fourth holiday.

[All photographs are really of the fourth dimension. --Mike]

The expansion of the universe could be a mirage, new theoretical study suggests: https://www.livescience.com/physics-mathematics/dark-energy/the-expansion-of-the-universe-could-be-a-mirage-new-theoretical-study-suggests
Good news for people who can't remember where they left things.

I do outreach for one of the local astronomy clubs. A frequent question concerns distance from Earth to what they're looking at in my scope. I fallback to "light years" in terms of how far away an object is. But I remember an example of the Solar System being the size of a baseball and the Andromeda galaxy would wind up about halfway to the Moon.

Great animation. That's the way I visualise the fourth dimension. We all know the three dimensions, x, y and z. The fourth is time, and is visualised by seeing (in your mind's eye) any object moving along a path as time passes. Only forward direction allowed, yes? Why not backwards? There's a question ...

That's four, but I'm danged if I can visualise a fifth or higher dimension. Especially the eleven required by string theory. I'll leave that to Sheldon.

Two things. In order of importance. Life changing is the event wherein you purchase a quality dehumidifier. Throw one in a spare bedroom, and add a portable clothes hanger. Snap! A drying room. You'll be stunned at how quickly washing dries when you put it in a room with 30% humidity. Ours uses stuff-all electricity too.

Thing two. That grain of sand to golf ball mental image is incredible. Why in the hell don't they teach that (and how important money management skills are) at junior levels of school? Maybe they do now? Getting old is both fun and just faintly confounding sometimes.

Thanks for listening!

There are many places that have scale solar system models, often integrated into walking/hiking or cycling routes. One I know runs along the Uetliberg, on the west side of Lake Zurich.


Boy, does it take you a long time to get to Pluto!

The Smithsonian has an article--


To give English children in the (I think) late 60s or early 70s an idea of the size of the solar system, a schools TV programme was made. It began in a classroom, where there was a piece of a sphere, representing part of the sun.

The camera moved out into the playground, where there was a tiny ball on a stick; Mercury. The cameraman then got into a helicopter which took off, heading in a straight line. Every so often flew over another ball on a stick; Venus, Earth, and so on.

The helicopter flew over many fields and hedges before it got to the last tiny ball; Pluto.

Oho! So I'm not the only one who forgets to dry their washing!

Your post was well timed, as I read it while on hold, ordering the right drive belt for my early 70s tumble dryer. It's taken a month to get the right part; not ideal in an English November!

We live in the past our entire lives. It takes some finite time for electrical impulses to travel from our sensors (eye, skin, etc) to our brain. By the time the brain is conscious of something, touch, shadow, etc., that moment is already in the past.

Seems to me that a good sci-fi plot could be built around this. I don't read sci-fi, maybe someone already has.

Size of the Universe (or even just the galaxy.) (Or, even!, just the nearest bit of it....): Voyager 1, which has been travelling for about 45 years, has not quite got 1 light-DAY from the sun; it has travelled about 1/500 of a light year. So: it will take Voyager 1 about 45 years x 500 to travel 1 light year, which is about 22,500 years. The Centauri system is around 4.5 light years away, which suggests that it will be about 100,000 years before Voyager 1 reaches that system (or travelled as far as it - I don't know in which direction the probe is actually travelling).

So: 100,000 years to get as far as the nearest star, other than our sun.

Mike said "Light, the fastest thing we know of, actually travels kinda slowly."

I'd like to see you travel faster!

I didn't think so, tough guy ;-)


I recently read (I hope this is accurate) that on the subject of celestial time scale, the north star, Polaris, has existed for less time than sharks have. Star-facts dot com puts it's age at 70 million years.


As far as youtube channels about space I can highly recommend the incredibly enthusiastic Dr Becky.

I think that you're missing out if you only have one set of sheets. We have different sheets for the different seasons. We just switched to our flannel sheets for the winter and it's so much nicer getting into bed in a cold room with flannel sheets on the bed then the cotton non-flannel sheets we use for the warm months.

Given the choice between a fried egg and one that is poached, the former always wins. The butter (or fat of choice) enables a smooth transit. Combination of butter with yolk IS manna from somewhere.

I don’t have a view on all the sciency stuff that appears here, even though it is fun to read.

Air-roasted coffee is also a necessity, my favourite is the type that is supplied by Michael Allpress which he calls “Art”.

NB: In either case, poached or fried, decent hand sliced white bread is a necessity.

“Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.”
― Douglas Adams, The Hitchhiker's Guide to the Galaxy

my favourite quip about the size of the universe remains this classic one from Douglas Adams. and it was between a trip to the chemist and your post that I was reminded of it. Happy TOP birthday, Mike. Here's to many more.

The comments to this entry are closed.



Blog powered by Typepad
Member since 06/2007