think about 1am

superflyninja wrote:

Vela wrote:

And never forget the Moon. Through a decent telescope it is captivating.

I was looking at the moon last night actually(partly to calibrate my finder scope and focus). I read that when it is not full(like now) is the best time to see it. Its pretty amazing. The shadows on the surface really makes the detail pop. Its one thing to  see images on screen but to be out in the open in pitch darkness actually seeing things with your own eyes(and scope) is something else.
Im useless with my binoculars though, cant hold them steady enough.

Interesting fact is the brightness of a full Moon. At 95℅ illuminated it's only half as bright as a full Moon. This is because the surface dust is actually small beads caused by high temperature meteor collisions, and they internally reflect light right back at you like a prism.

SpaceGazelle wrote:

superflyninja wrote:

Vela wrote:

And never forget the Moon. Through a decent telescope it is captivating.

I was looking at the moon last night actually(partly to calibrate my finder scope and focus). I read that when it is not full(like now) is the best time to see it. Its pretty amazing. The shadows on the surface really makes the detail pop. Its one thing to  see images on screen but to be out in the open in pitch darkness actually seeing things with your own eyes(and scope) is something else. Im useless with my binoculars though, cant hold them steady enough.

Interesting fact is the brightness of a full Moon. At 95℅ illuminated it's only half as bright as a full Moon. This is because the surface dust is actually small beads caused by high temperature meteor collisions, and they internally reflect light right back at you like a prism.

Thats genuinely fascinating. Never knew that.

This might be a silly question then but that would also be why astronauts wouldn't want to be out during high noon on the lunar surface? At least near the equator with the sun close to zenith.

Yeah, that wouldn't help but I guess what's the intensity of the reflected light across various wavelengths. Like how Earth mainly reflects in IR or rather re emits in IR over land and water will also reflect in visible spectrum too. 

Would walking on the moon at noon be like a double dose or giving increased exposure like a UV bed.

The satellites are a lot higher up, and most of those meteors are speck sized particles. The satellites are around 20k miles up, but meteors burn up around 60 miles up, so there's a load more space between the satellites for the same coverage and also between the meteors until they get closer, although it wouldn't surprise if they do get hit regularly. The biggest part of the satellite is the solar panels and I'd guess that every now and again individual cells do get hit but the rest of the cells in the (wing/panel) have enough to continue to power the thing

Some of them are, I think they'd need to be around that sort of size when they hit the atmosphere for any part of them to reach the ground, but most of what you see is tiny specks of dust, just they go so quick they burn really brightly

GooberTheHat wrote:

That makes sense. I didn't know meteors were so small, I always assumed they were golf ball/tennis ball size.  Cheers.

They're all different sizes that exponentially favour the smaller size. You can see this quite easily by putting a house brick in a bag a hitting it a few times with a hammer and then looking at the pieces. In fact, in pre-computer modeling days this is more or less what astronomers used to do. The meteor that killed the dinosaurs was probably only about 7 or 8 miles across and it'll happen again someday.

SpaceGazelle wrote:

Vela wrote:

This might be a silly question then but that would also be why astronauts wouldn't want to be out during high noon on the lunar surface? At least near the equator with the sun close to zenith.

They went at lunar dawn because it gets to around 200 degrees at noon.

How long is a lunar day? Twenty eight days or thereabouts.

Vela wrote:

Aha. Yes. Two weeks of day then two weeks of night.

Yar, it's tidally locked to the Earth and so "turns" once a month.

SpaceGazelle wrote:

Vela wrote:

Aha. Yes. Two weeks of day then two weeks of night.

Yar, it's tidally locked to the Earth and so "turns" once a month.

So it's not just coincidence that it spins in the same amount of time it takes to orbit?

Just if it's "locked" does that imply that the side of the moon we see is perhaps denser than the other side and that is what keeps it facing this way gravity acting harder, or have I grabbed the wrong stick end

Hmm, colour me intrigued. I would have thought it was too small to have a core and crust, but I definitely know what I'll be reading about this afternoon, cheers for piquing my interest

Ahh, still massively intrigued, the bulge makes sense given it is kinda like the moon is attached by an invisible stick

That makes sense I remember an Arthur C Clarke book about going to Mercury and it had a permanent day side and night side in that so yeah I think it is

Cheers will do