It's been a while, so let's catch up with the listener questions. We've got some easy ones, some hard ones and probably some impossible ones. We talk about our universe as a black hole, tidal locking of planets like Uranus, colours of stars at different ages, our universe's birthday and more.

<strong><a href="http://media.libsyn.com/media/astronomycast/AstroCast-070917.mp3">Episode 54: Questions Show #6(17.5MB)</a></strong><br />&nbsp;<br />

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I'll put this question in this topic too, because it really bugs me:

I just listened to this episode and one thing sounded a bit weird to me, I hope you don't mind my asking it here on this topic:

Which way is it that Uranus really rotates; rotational axis
A) always pointing (more or less) in the same direction (on the "firmament"), or
B) always pointing at the Sun?

It's a bit hard for me to find the right words to explain these two models, but perhaps this picture (that I drew myself just now helps you to understand what I mean:

http://img486.imageshack.us/img486/1843/uranus1od1.jpg

I've always thought that it was A), but in this episode I thought I heard Fraser and/or Pamela mention something like B) somewhere. What force makes a planet rotate (or is it revolve? Go around the Sun) this way? Though I might well have misunderstood something here, because (as you can probably tell) english isn't my native tongue...

Now what? The whole show seems to be gone! At least there seems to be no link to it on the front page...

That's strange, I see it. It's here:
http://www.astronomycast.com/stars/e...stions-show-6/

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Fraser Cain
Publisher
Universe Today - Free space news delivered by email every weekday.

Nope, for me that's just an empty page. And last (or first, depending on how you look at them) podcast on the main page is ep. 53. But ep. 54 WAS there just a few days ago! I use Opera, but same thing with IE, I just checked. Weird...

I can find it on the Archive list, though, but nowhere else.

I have a question. Why is it that now that I have listened to Astronomy cast all other pod casts seem boring and uneducated?

It's back! Sorry for the random disappearance. It seems a checkbox got clicked that shouldn't have.

-Rebecca B-F
Assistant Producer
Astronomy Cast

Yeah, this kinda threw me too. If the "North Pole" of Uranus is always pointed at the sun, the planet would actually have two axes of rotation since it would have to slowly spin to keep one end toward the sun as it orbited...right? Maybe I didn't listen close enough. Little help?

Edit:
Found my answer. Wikipedia says (A).
"Near the time of Uranian solstices, one pole faces the Sun continually while the other pole faces away ... At the other side of Uranus' orbit the orientation of the poles towards the Sun is reversed. Each pole gets around 42 years of continuous sunlight, followed by 42 years of darkness."

Pamela mentioned these two things:

"...somewhere else in the universe that is maybe completely isolated and sitting there going, "the universe is expanding around me but I'm not going to move."

and:

"The dude who's not moving is the one that celebrates it first"

So, is there then, this point in space from which the gridwork of the universe stretches from in all directions? ... an absolute zero in terms of relative motion? And if so, would this not be the "real" big bang birthday to which all other points in space would have adjust their clocks to celebrate?

A few episodes back, Pamela mentioned how the clocks on earth orbit satellites have to be adjusted periodically, forward in time, to match real time on earth. Is there some formula that calculates this same type of adjustment to match the "real" time at the center of the universe? So the further away we are from center, the more of an adjustment we have to make?

__________________
"The only true wisdom is in knowing you know nothing." - Socrates