Gill Head: Kirkby Luneside's neighbour

[Peter Kazmierczak]

I can totally understand losing the modelling mojo.

 

This weekend there is a model railway exhibition just 3,000ft (as the crow flies) from our house. My layout is probably the closest one to the show not actually there! But the thought of being in a stuffy hall looking at bits of track on pieces of wood, doesn't really appeal.

[Donw]

It is good to hear from you Jeff and Andy too. The really good news is that you are both doing other things you really enjoy. It it always a concern that when someone is not posting it is down to health or family issues. 

Glad to hear you have someone converting the locos for you.

 

Regards to you both

 

Don

[Sasquatch]

Was wondering just the other day where you'd got to Jeff. You know, we haven't seen the moon since before Christmas, (it's very damp and extremely cloudy but at least we've escaped any flooding). Aren't those Chinese up there stealing all the cheese, shame because "I do like a bit of gorgonzola"!😁 (Cheesy grin emoji)

I'm looking forward to seeing the layout and any progress, when you're ready of course.

And, well done with getting published, that's always a good feeling of accomplishment, Bravo!

 

Regards Shaun. 

[Physicsman]

Don, Shaun - thanks for the comments. And Peter, you've been modelling longer than I have, so it's good to know that others suffer from this (almost illogical) loss of interest.

 

As promised, a few Moon pics - I have to keep Ade happy! These are compressed Jpegs - much smaller files than the original TIFs. But they do stand a bit of enlargement. To give a sense of scale, the largest craters in these images are around 60 - 80 miles (100 - 130km) in diameter.

 

North east area of the Moon:

 

 

One of the large "seas" - Mare Serenitatis - a huge (400 miles across) lava bed....

 

 

The 60 mile wide crater Plato, with internal shadows from the mountains on its Western wall:

 

 

The Caucasus Mountains and "Alpine Valley" (at upper left corner):

 

 

South eastern area of the Moon - craters everywhere!

 

 

Hope these are of interest.

 

Hopefully, there may be some railway-related stuff on here later in the Spring!

[Andrew P]

Bloomin WOWSER  Jeff, that is fascinating, and funnily enough I've been watching Live streaming from the ISS over the last few weeks. More anytime as far as I'm concerned

[Andrew P]

Question Jeff @Physicsman any ideas why all moon craters are round, and yet here on earth, Rock and natural mountain formations can take on any shape, such as Snowdon and Ben Nevis for example? Most Moon ones also appear to have a centre spot of some sort as well.

[Tortuga]

2 hours ago, Andrew P said:

Question Jeff @Physicsman any ideas why all moon craters are round, and yet here on earth, Rock and natural mountain formations can take on any shape, such as Snowdon and Ben Nevis for example? Most Moon ones also appear to have a centre spot of some sort as well.

Different processes of formation @Andrew P.

The majority of mountains on Earth are the result of plate tectonics and associated volcanic activity, together with millions of years of weathering and erosion.

The craters on the Moon are predominantly the result of impacts from asteroids/meteors (one name applies and I’m not sure which).

 

Thanks to the Moon and the atmosphere, Earth doesn’t suffer a huge number of significant asteroid impacts - the Moon catches the brunt of them or they burn up entering the atmosphere - and the craters produced by those that do hit the ground, tend to get obliterated in short order* thanks to the processes of weathering and erosion. The Moon has no atmosphere and has been tectonically inactive for a looooong time, so there’s nothing working to obliterate the impact craters or produce mountain ranges like on Earth.

 

*a few million years - short in the geological sense of time.

[Andrew P]

53 minutes ago, Tortuga said:

Different processes of formation @Andrew P.

The majority of mountains on Earth are the result of plate tectonics and associated volcanic activity, together with millions of years of weathering and erosion.

The craters on the Moon are predominantly the result of impacts from asteroids/meteors (one name applies and I’m not sure which).

 

Thanks to the Moon and the atmosphere, Earth doesn’t suffer a huge number of significant asteroid impacts - the Moon catches the brunt of them or they burn up entering the atmosphere - and the craters produced by those that do hit the ground, tend to get obliterated in short order* thanks to the processes of weathering and erosion. The Moon has no atmosphere and has been tectonically inactive for a looooong time, so there’s nothing working to obliterate the impact craters or produce mountain ranges like on Earth.

 

*a few million years - short in the geological sense of time.

Thank you, great answer, makes sense to me now. Cheers. 

[Physicsman]

Hi Andy.

 

Good question about the Moon crater shape and thanks to "Tortuga" for providing a good response.

 

For many years the majority of astronomers considered the Moon's craters to be of volcanic origin, like the calderas of shield volcanoes - because of the circular shape. This idea was prevalent in Europe, though many in the US pointed out the difference in scale on the Moon. Many lunar craters are over 100 miles in diameter, and the "hole" at the summit of volcanoes rarely exceeds one mile.

 

Obvious though this was, the volcanic idea persisted. People wondered how incoming impactors (large lumps of rock, some travelling at over 50,000mph and massing thousands of tons) hitting the Moon at various angles could produce a circular shape. We now know the complete obliteration of the impactor is effectively an exploding "bomb" acting from a point - with some explosions billions of times more powerful than Hiroshima. So, whatever direction the rock hits, a circular depression (crater) is produced.

 

For craters over around 20 miles across, the expanding shock wave (as in an earthquake) causes a rebound of material at the centre. Many larger craters have mountain groups - "central peaks" - in the middle.

 

The Earth was also subjected to the same intense bombardment as the Moon. Most of this occurred over 4 billion years ago. Some impacts still occur today, but only relatively small objects, most of which disintegrate as they pass through the atmosphere. The crater record of the Earth has largely been wiped out over time because of the weathering effects of the atmosphere, oceans etc. And the Earth is two thirds covered in water - the Moon has no atmosphere and the bare surface retains the impact record.

 

Fundamentally, the circular shape of lunar craters is because of the equi-directional nature of the energy release/explosions no matter what direction the impact happens.

 

To put things into perspective, the shape and origin of the Moon's craters has only been "settled" since the late 1940s, with Apollo data confirming the idea. Then again, the Earth's tectonic plate features - fundamental to explaining much of the Earth's surface - has only been confirmed since the middle of the 20th century.

 

Our understanding of planetary bodies has come a long way in the last century, with plenty more to learn!

 

And Andy - I used good old Imperial units since you hate metric!!

 

Apologies to go on here.....barely scraping the surface. I hope the pictures are enjoyable, whatever the science behind them!

[AdeMoore]

6 hours ago, Physicsman said:

Don, Shaun - thanks for the comments. And Peter, you've been modelling longer than I have, so it's good to know that others suffer from this (almost illogical) loss of interest.

 

As promised, a few Moon pics - I have to keep Ade happy! These are compressed Jpegs - much smaller files than the original TIFs. But they do stand a bit of enlargement. To give a sense of scale, the largest craters in these images are around 60 - 80 miles (100 - 130km) in diameter.

 

North east area of the Moon:

 

 

One of the large "seas" - Mare Serenitatis - a huge (400 miles across) lava bed....

 

 

The 60 mile wide crater Plato, with internal shadows from the mountains on its Western wall:

 

 

The Caucasus Mountains and "Alpine Valley" (at upper left corner):

 

 

South eastern area of the Moon - craters everywhere!

 

 

Hope these are of interest.

 

Hopefully, there may be some railway-related stuff on here later in the Spring!

Outstanding pics Jeff, love em! Makes a welcome detour from 4’8” an a alf stuff! 🤣😉.

[Peter Kazmierczak]

Looks like you got as close as Jim Lovell did on his two Apollo trips. So do we now call you "Rocket Man"?

 

In the second image, is that wriggly line a drystone wall?

Edited February 11 by Peter Kazmierczak

[sjp23480]

1 hour ago, Physicsman said:

Hi Andy.

 

Good question about the Moon crater shape and thanks to "Tortuga" for providing a good response.

 

For many years the majority of astronomers considered the Moon's craters to be of volcanic origin, like the calderas of shield volcanoes - because of the circular shape. This idea was prevalent in Europe, though many in the US pointed out the difference in scale on the Moon. Many lunar craters are over 100 miles in diameter, and the "hole" at the summit of volcanoes rarely exceeds one mile.

 

Obvious though this was, the volcanic idea persisted. People wondered how incoming impactors (large lumps of rock, some travelling at over 50,000mph and massing thousands of tons) hitting the Moon at various angles could produce a circular shape. We now know the complete obliteration of the impactor is effectively an exploding "bomb" acting from a point - with some explosions billions of times more powerful than Hiroshima. So, whatever direction the rock hits, a circular depression (crater) is produced.

 

For craters over around 20 miles across, the expanding shock wave (as in an earthquake) causes a rebound of material at the centre. Many larger craters have mountain groups - "central peaks" - in the middle.

 

The Earth was also subjected to the same intense bombardment as the Moon. Most of this occurred over 4 billion years ago. Some impacts still occur today, but only relatively small objects, most of which disintegrate as they pass through the atmosphere. The crater record of the Earth has largely been wiped out over time because of the weathering effects of the atmosphere, oceans etc. And the Earth is two thirds covered in water - the Moon has no atmosphere and the bare surface retains the impact record.

 

Fundamentally, the circular shape of lunar craters is because of the equi-directional nature of the energy release/explosions no matter what direction the impact happens.

 

To put things into perspective, the shape and origin of the Moon's craters has only been "settled" since the late 1940s, with Apollo data confirming the idea. Then again, the Earth's tectonic plate features - fundamental to explaining much of the Earth's surface - has only been confirmed since the middle of the 20th century.

 

Our understanding of planetary bodies has come a long way in the last century, with plenty more to learn!

 

And Andy - I used good old Imperial units since you hate metric!!

 

Apologies to go on here.....barely scraping the surface. I hope the pictures are enjoyable, whatever the science behind them!

Jeff,

 

Great pictures.

 

What I find interesting is that we can see the craters at all. As I understand it, as the moon orbits the Earth the same "side" of the moon faces the Earth all the time. 

 

At some time in the dim and distant, that side of the moon must have had a different aspect be hit by meteors. 

 

I also find the whole mechanics of eclipses interesting. The size of the moon and it's distance from the Earth are exactly the right size to obscure the sun. 

 

Fascinating stuff

 

Steve

 

 

[MarshLane]

Stunning Images Jeff, you are going to have stop flying your drone over there so often tho - I mean if you can do it, while sat surfing rmWeb, what excuse does NASA have for these big rocket things!

 

Well done on the photography tho, really good. I presume they are focus stacked?  What was the original number of images for the composition?

 

Rich

[John Besley]

BTW how big are the craters that give us the 'face yawning' that we see on full moon...

 

Don't suppose you can see any NASA stuff up there?... Just asking for a friend 

[Winslow Boy]

It is my understanding that the moon is very gradually moving further away from earth. Can't remember why, but those bright people at NASA got a mirror left there and every so often shine a laser at it. Each time they do it they get a slightly longer signal back, proving that it is moving away.

[Donw]

Superb pictures Jeff. With regard to the craters are there any new ones big enough to show up? What sort of size Asteroid would be needed to create a 100 mile wide crater? I think I read that there have been about 18 recorded on Earth in the last 10o years or so, obviously many smaller ones have not been recorded. The earth is a lot bigger so must get more than the moon.

 

Don

[Donw]

5 minutes ago, Winslow Boy said:

It is my understanding that the moon is very gradually moving further away from earth. Can't remember why, but those bright people at NASA got a mirror left there and every so often shine a laser at it. Each time they do it they get a slightly longer signal back, proving that it is moving away.

 

At some point we will no longer get total eclipses on earth as it moon away.  There is also the possibility it may affect the slowing of the earths day by the effect of the moon. As it moves away the braking effect could reduce making the earths day slow less. Mind you the loss of total eclipses is about 1.2 billion years away so no panic there.

 

Don 

[Physicsman]

Blimey!!

 

I only looked on here as my Hotmail informed me that someone had sent me a PM. There's a fully-fledged astronomy course-worth of questions here! I'll try my best to give some "ball park" estimates to some of them.

 

Impactor sizes - it all depends on the speed of impact, as well as the size of the object. The image, below, shows a picture of a near Full Moon with the "left eye" of the Man in the Moon circled in yellow. This is the "Mare Imbrium" - it's about 1100km (700 miles) across. Around 4.2 billion years ago an asteroid, estimated at around 200-300km across, hit the Moon travelling at around 60,000mph (100000km/h). This impact gouged out the Imbrium area and, over 200-300 million years it gradually filled with lava to look similar to it does today. I did a quick estimate of the mass of the asteroid - it would be around 1000 million million tonnes.

 

 

A typical large lunar crater of around 100km diameter would need an impactor around 10 miles (16km) across. These would have been thousands of times more common than the Imbrium asteroid - this is about the size of the dinosaur-wipe-out asteroid from 64 million years ago.

 

Steve, the Moon's rotation is "tidally locked" - it makes one rotation relative to the Sun in the time it rotates once round the Earth. So it always keeps the same side towards us. The large basins - such as Imbrium - are visible to the naked eye, but individual craters require a telescope.

 

Yes, the Apollo missions left behind prism reflectors as part of the "ALSEP" package. A laser pulse from Earth is reflected off the reflector and part of the beam returns to Earth. The time it takes to go there-and-back is measured and the distance to the Moon calculated - laser light travels at the speed of light. The Moon is moving away from the Earth by around 3 to 4cm a year. The Moon's gravity exerts a pull on the Earth and can move water in the oceans (one cause of tides). This "sloshing" slows down the rotation of the Earth - our days are getting longer. The angular momentum of the Earth-Moon system remains approximately constant so to compensate for a slowing Earth, the Moon's orbit has to increase - it moves away.

 

I'll do another batch of "woffle" tomorrow - time for my coffee!! (Rich, I'll outline the "photo" method I use).

 

Thanks for asking - remember, my answers are generalities, not definitive.

Edited February 12 by Physicsman

[Physicsman]

John, sorry, I meant to answer the NASA stuff question.

 

Diffraction, the re-directing of waves when they pass through a gap - such as light into a telescope - fundamentally limits the detail we can see. Even the largest telescopes on Earth or in Earth orbit can't see details on the Moon smaller than around 100 metres. And that's under perfect conditions. 

 

So a lunar module is completely invisible from Earth. However, satellites such as the Lunar Reconnaisance Orbiter (LRO) have imaged all the Apollo landing sites from low lunar orbit. The lander with its shadow, tracks created by the rovers etc are very clearly visible. However, the conspiracy theorists just claim this is all fake. Complete idiots!

Edited February 12 by Physicsman

[Andrew P]

I have learnt so much in the last half hour. 👍 truly absorbing, and I can relate to your fascination Jeff, @Physicsman 

 

 

I did try to read it all to my Good Lady, but was told to SHUT UP,  at this time in the morning.🤪

[Physicsman]

3 hours ago, Andrew P said:

I have learnt so much in the last half hour. 👍 truly absorbing, and I can relate to your fascination Jeff, @Physicsman 

 

 

I did try to read it all to my Good Lady, but was told to SHUT UP,  at this time in the morning.🤪

 

I always knew Dee had a modicum of good sense!

 

I mean, all that gobbledegook I've put on here!!

 

Glad to hear that some of it made sense. I could write about this stuff for hours. And the practical part is the best - outside taking the data, even if your "whats-its" are being frozen off!

[Physicsman]

Rich, here's a brief answer to your imaging question.

 

If you refer to the first or second images further up this page....

 

Each of these is actually a mosaic of 6 separate pictures, merged together. Each component picture is made from 1000 separate "frames". So the top two pics are effectively a stack of 6000 separate images.

 

For each picture I take, in effect, 10000 photos using my planetary camera working at 80 frames per second (I've got a couple of others that I use at around 110fps, but they are wider field). So imaging the area chosen takes about 10000/80 = 125 seconds. I then shift the telescope slightly to an adjacent area and repeat. In this case I did 6 adjacent areas.

 

From each set of 10,000 pics, I choose the best 1,000 (10%). The 6 lots of 1,000 are then merged/composited to produce a final image. This can then be contrast adjusted, but I make as few adjustments to the basic data as I can. My aim is to produce as good a rendition of what I see through the telescope/on the laptop screen as I can.

[MarshLane]

15 hours ago, Physicsman said:

However, the conspiracy theorists just claim this is all fake. Complete idiots!

 

Well obviously its fake - my nephew took his remote controlled buggy over the sands at Cleethorpes ... if you put a picture of the tracks from that into black and white its just as good as Nasa's 'close-up' shots of the moon ... a man on the mood pah! as if! 😉  Sorry I really do need to stop letting sarcasm take over!

 

Thanks for the description of your photograph process. Fascinating.  I have done video filming work running a 6K camera a 120fps in the past and know the amount of data that comes from that, so can imagine the processing power for compiling that lot.  Well worth it though, the quality of your photos speak for themselves.  Keep up the good work.

 

Rich

Edited February 12 by MarshLane

[Physicsman]

Cheers Rich.

 

I store all the data on SSDs  - and a 10,000 frame video comes in at 20Gb,  so it soon accumulates.

About 15Tb since August 2022.

 

 

[AdeMoore]

Really interesting, learning a lot from the above.

Thanks for taking the time to explain it Jeff.

I didn’t realise we were always looking at the same side of the moon!

So presumably if you want to photograph the hidden sides you can only do that from space?

or have I miss read?