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Old 01-06-2008, 21:22
t0dger
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Phil Archer has been rather taken with all things astronomical since he got a new telescope. I wonder if that, even only in part, might be responsible for this thread?

(Currently, Phil is making pictures of stars which, according to Ruth, have got some kind of 3D effect )
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Old 08-06-2008, 18:29
Ricardodaforce
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Another book recommendation for you. It's an oldie though. I'm currently reading Tom Wolfe's The Right Stuff. Excellent read.
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Old 12-06-2008, 00:29
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Apparantly Gordo Cooper is due a space burial this month.
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Old 13-06-2008, 15:30
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It would appear that Discovery has a slightly damaged tail fin. It's being inspected at the moment.
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Old 15-06-2008, 13:55
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Although it's taking a risk, I'll stick my neck out and make a few predictions about what the Phoenix lander will find at Mars' north pole and here they are:

* In terms of geology (or should that be areology?), there'll be aluminosilicate minerals, magnesium-iron silicates, iron oxides and iron sulphides;
* There will be water present, e.g. in the form of ice permafrost under the surface;
* There will be no conclusive signs of life found.

This is a difficult one but even if life did evolve on Mars and survive numerous upheavals, it probably only got to the stage of colonial/filamentous bacteria type level. I think they are looking in entirely the wrong place for life.

I would suggest the putative northern ocean shoreline to look for microfossils but that will probably take a crewed mission and the other place I would search is where there is any residual geological thermal activity that could keep water liquid and warm in rock layers and serve as a have for micro-organisms. Again, this would mean a lot of drilling and a crewed mission. I'd like to see a surface sample return mission like the Soviets did on the Moon.

For what it's worth, I think it's safe to say that any life on Mars is not abundant, widespread or diverse. Indeed, I would not be surprised if the only microbes to be found were ones that had hitched a lift from Earth on the various landers from the Soviet Union and United States in the 1970s. There is a precedent for this already.

The Apollo 12 lunar mission land a few hundred metres away from the Surveyor 3 probe and the retrieved samples from this probe contained dormant bacteria which were subsequently revived on Earth. At the time of writing I cannot recall from memory which species were involved though.
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Old 16-06-2008, 09:37
njp
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The Apollo 12 lunar mission land a few hundred metres away from the Surveyor 3 probe and the retrieved samples from this probe contained dormant bacteria which were subsequently revived on Earth. At the time of writing I cannot recall from memory which species were involved though.
Streptococcus mitis. However, whilst the ability of some strains to survive such conditions is not in question, it seems possible that the Surveyor 3 results may have been the result of a breach of sterile procedure in the lab handling the samples.
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Old 17-06-2008, 21:08
Ricardodaforce
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Another book recommendation for you. I just bought at hardback by Andrew Chaikin called Space. It is packed with outstanding photography. Loads of Mercury and Gemini images I've never seen.
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Old 02-07-2008, 18:06
Ricardodaforce
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Amazing. Over 30 years since launch both Voyagers out outside of our Solar System and still sending data back to Earth. In 5-7 years Voyager 1 will be in interstellar space and still sending back data. See here.
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Old 05-07-2008, 23:25
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Nice video here showing how NASA intend to get back to the moon.
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Old 09-07-2008, 02:57
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Details of a new documentary about the Apollo moon missions here.
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Old 09-07-2008, 03:10
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NASA has now released details of the remaining shuttle flights before the fleet is retired.
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Old 09-07-2008, 09:30
jon8769
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Details of a new documentary about the Apollo moon missions here.
Keep an eye out for this everyone. Its very good indeed.

http://dsc.discovery.com/tv/nasa/nasa.html
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Old 15-07-2008, 19:04
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Interesting article claiming the Chinese could put a man on the moon within the next decade.
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Old 20-07-2008, 15:42
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The very latest research from the Mars Reconnaissance Orbiter has just been published in the current editions of Nature and Nature Geoscience magazines.

The analysis of the photos sent back from this orbiting probe have indicated that water was once widespread on Mars and that it was likely to have persisted a long time on Mars. The researchers found evidence of flowing rivers, river deltas and large lakes.

As the life we know is dependent on the presence of water, this increases the possibility that primitive microbial life could have at least got started on Mars but we shall have to wait and see. The next major development will be an uncrewed sample and soil return mission before the end of the next decade.

This can be compared with the Soviet Union's Luna 16, 20 and 24 missions which all successfully returned lunar soil samples to Earth in the 1970s. These uncrewed missions did not receive anything like the publicity of the American Apollo missions but they brought back about 275 grammes of lunar material in total for analysis. The full story can be seen here at http://www.nature.com/nature/journal...ture07097.html, http://www.nature.com/nature/journal...ture07097.html.
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Old 20-07-2008, 15:50
HenryGarten
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Ah if Luna 15 had not crashed I am sure you would have heard a great deal about it.
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Old 20-07-2008, 16:00
CASPER1066
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If we have a telescope good enough to reach the moon, why cant see pictures of the lunar landing module or anything like that ??..

can someone tell me ?..thanks
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Old 20-07-2008, 16:06
HenryGarten
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If we have a telescope good enough to reach the moon, why cant see pictures of the lunar landing module or anything like that ??..

can someone tell me ?..thanks
You have not long to wait. A probe to do just that is due away in November.
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Old 20-07-2008, 16:08
Carlos_dfc
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If we have a telescope good enough to reach the moon, why cant see pictures of the lunar landing module or anything like that ??..

can someone tell me ?..thanks
It's too far away (quarter of a million miles)
Telescope resolution is a direct function of the diameter of the objective lens or mirror.
To image something a couple of metres across, at a distance of quarter of a million miles, you'd need a telescope with an objective diameter of hundreds of metres.

The best ground based telescopes, and even the 'Hubble' can only manage to detect something the size of a football pitch, at that distance - and by 'detect', I mean a football pitch would only be a couple of pixels on the camera sensor - no detail, just a 'spot'

However......
Just a few days ago, the Japanese 'SELENE orbiter (which is taking high-res images of the Moon's surface) has imaged the Apollo 15 landing site, and picked up the plume of dust, disturbed by the Apollo 15 lander, when it blasted off on it's way home.
http://www.universetoday.com/2008/07...g-site-images/
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Old 20-07-2008, 16:12
CASPER1066
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You have not long to wait. A probe to do just that is due away in November.
thanks......ill be interested to see that........

Is is also true that Nasa have lost all the orignal films from the landings....
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Old 20-07-2008, 16:14
HenryGarten
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thanks......ill be interested to see that........

Is is also true that Nasa have lost all the orignal films from the landings....

Here is the link. See http://lunar.gsfc.nasa.gov/mission.html
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Old 20-07-2008, 16:14
CASPER1066
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It's too far away (quarter of a million miles)
Telescope resolution is a direct function of the diameter of the objective lens or mirror.
To image something a couple of metres across, at a distance of quarter of a million miles, you'd need a telescope with an objective diameter of hundreds of metres.

The best ground based telescopes, and even the 'Hubble' can only manage to detect something the size of a football pitch, at that distance - and by 'detect', I mean a football pitch would only be a couple of pixels on the camera sensor - no detail, just a 'spot'

However......
Just a few days ago, the Japanese 'SELENE orbiter (which is taking high-res images of the Moon's surface) has imaged the Apollo 15 landing site, and picked up the plume of dust, disturbed by the Apollo 15 lander, when it blasted off on it's way home.
http://www.universetoday.com/2008/07...g-site-images/
thanks for that......im sure if it has picked up a plume of dust it should be able to pick up a lunar landing module and all the things which were left behind?,,,
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Old 20-07-2008, 16:18
CASPER1066
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thanks Henry.........#
It was always argued that radiation was too strong for anyone to have gone to the moon in 60's. That we would need a shield 6 inchs thick which would have made it to heavy.......

Im sure this will put all the speculation to rest..........
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Old 20-07-2008, 16:18
Trinitrotoluene
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If we have a telescope good enough to reach the moon, why cant see pictures of the lunar landing module or anything like that ??..

can someone tell me ?..thanks
The reason is that it's simply to small to be seen (even with hubble). It would be like trying to read a book that was 30 miles away with some binoculars! It can be shown that it can't be seen with a little maths:

Let's say the largest object on the moon was 5 metres in diameter, I picked 5 because it's a nice round number! The distance to the moon is roughly 384,000 kilometres.

Angular Size = 5 / 384,000,000 = 13 billionths of a Radian

To convert from from Radians to degrees:

In degrees = (1.3 x 10-8) x 180 / Pi = 750 billionths of a degree across

Ok, so we've obtained in degrees the area that we would have to look at to be able to see that particular object, now I will tie this into hubble.

Astronomers use 'arcseconds' instead of degrees. There are 3600 arc seconds in a degree. If we do the maths 750 billionths of a degree x 3600 we get around 0.0026 arc seconds, but because we approximated with the distance I'll round this upto 0.003 arcseconds.

So, I hear you ask? What can hubble see? Our eye can see 60 arcseconds, The best telescope on the ground can see objects 0.5 arcseconds in size, hubble can see more clearly, upto 0.05 arcseconds in size. That makes the moon landing equipment 18 times smaller than what hubble can see. Even if it was 18 times bigger it would resolve to one pixel, to put that in perspective you probably have about 800 thousand pixels on your monitor right now!

Now then, that isn't the only problem! The moon is moving across the sky at 0.5 arcseconds due to it's orbit around earth, you can probably see the problem all ready! It would be like trying to take a sharp picture of a train whizzing by!

I hope this answers your questions,

TNT
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Old 20-07-2008, 16:19
HenryGarten
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thanks......ill be interested to see that........

Is is also true that Nasa have lost all the orignal films from the landings....
I very much doubt that. However I do believe that the blueprints for building the lunar module have been lost.
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Old 20-07-2008, 16:22
CASPER1066
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The reason is that it's simply to small to be seen (even with hubble). It would be like trying to read a book that was 30 miles away with some binoculars! It can be shown that it can't be seen with a little maths:

Let's say the largest object on the moon was 5 metres in diameter, I picked 5 because it's a nice round number! The distance to the moon is roughly 384,000 kilometres.

Angular Size = 5 / 384,000,000 = 13 billionths of a Radian

To convert from from Radians to degrees:

In degrees = (1.3 x 10-8) x 180 / Pi = 750 billionths of a degree across

Ok, so we've obtained in degrees the area that we would have to look at to be able to see that particular object, now I will tie this into hubble.

Astronomers use 'arcseconds' instead of degrees. There are 3600 arc seconds in a degree. If we do the maths 750 billionths of a degree x 3600 we get around 0.0026 arc seconds, but because we approximated with the distance I'll round this upto 0.003 arcseconds.

So, I hear you ask? What can hubble see? Our eye can see 60 arcseconds, The best telescope on the ground can see objects 0.5 arcseconds in size, hubble can see more clearly, upto 0.05 arcseconds in size. That makes the moon landing equipment 18 times smaller than what hubble can see. Even if it was 18 times bigger it would resolve to one pixel, to put that in perspective you probably have about 800 thousand pixels on your monitor right now!

Now then, that isn't the only problem! The moon is moving across the sky at 0.5 arcseconds due to it's orbit around earth, you can probably see the problem all ready! It would be like trying to take a sharp picture of a train whizzing by!

I hope this answers your questions,

TNT
thank you very much for taking the time......your way ahead of me......but I get your point......
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