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Old 10-09-2009, 11:15
njp
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Sometimes an image prepared for public release is just a nice, glossy centrefold and is not a very 'true' representation of the real thing.
Can you give an example?

How "true" is any image that can only be seen at all with the help of very expensive optics? How about microscopy, where the specimens have to be stained or (in the case of electron microscopy) subjected to very extensive preparation (such as coating them in metal)?

I can see what you are hinting at, but you did your argument no favours by making a comparison with the sort of image manipulation routinely performed by glossy magazines.
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Old 10-09-2009, 11:16
Assa2
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Old 10-09-2009, 11:28
Assa2
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Can you give an example?

How "true" is any image that can only be seen at all with the help of very expensive optics? How about microscopy, where the specimens have to be stained or (in the case of electron microscopy) subjected to very extensive preparation (such as coating them in metal)?

I can see what you are hinting at, but you did your argument no favours by making a comparison with the sort of image manipulation routinely performed by glossy magazines.
I realise that and in hindsight it was perhaps not the best analogy to use.

The essential point I was trying to make was that typically the images are colourised to demonstrate the chemical compositions of an object i.e. a nebula, so in truth there is no green or orange or yellow or rusty red or what ever. Or the colourisation is used to enhance detail not ordinarily visible.

Quote taken directly from the NASA sight you linked to:

Color in Hubble images is used to highlight interesting features of the celestial object being studied. It is added to the separate black-and-white exposures that are combined to make the final image.

Creating color images out of the original black-and-white exposures is equal parts art and science.

We use color:
• To depict how an object might look to us if our eyes were as powerful as Hubble
• To visualize features of an object that would ordinarily be invisible to the human eye
• To bring out an object's subtle details.
The vast majority of the public who see these images would not have a clue about that. It really doens't matter as long as people see the images and are inspired by them in some way.
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Old 10-09-2009, 11:43
Assa2
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This is a perfect example of what I'm talking about:

http://www.hubblesite.org/gallery/be...olor/eagle.php

This is one of Hubble's most famous and beautiful images. Unfortunately it's not a 'true' reflection of what the Eagle Nebula looks like. Red light has been selectively colourised as either green (from hydrogen) or red (from Sulphur). There has also been some other manipulation carried out to clean up the image which they don't talk about here. This image took days to prepare by skilled and very artistic people specifically for public consumption to highlight a breakthrough observation in star formation.
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Old 10-09-2009, 11:48
Assa2
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This is a perfect example of what I'm talking about:

http://www.hubblesite.org/gallery/be...olor/eagle.php

This is one of Hubble's most famous and beautiful images. Unfortunately it's not a 'true' reflection of what the Eagle Nebula looks like. Red light has been selectively colourised as either green (from hydrogen) or red (from Sulphur). There has also been some other manipulation carried out to clean up the image which they don't talk about here. This image took days to prepare by skilled and very artistic people specifically for public consumption to highlight a breakthrough observation is star formation.
Was doing some digging on the Eagle Nebula 'pillars of creation' and it seems they may be no more! A nearby star that went super-nova may have 'blown' the nebula away 6,000 years ago. We won't see the result for another 1,000 years or so.
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Old 10-09-2009, 11:49
BeethovensPiano
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There has also been some other manipulation carried out to clean up the image which they don't talk about here. This image took days to prepare by skilled and very artistic people specifically for public consumption to highlight a breakthrough observation is star formation.
Of course there is going to be some process to clean up the image, every camera in space will have this applied. You have image "noise" produced by current in the CCD chip itself during long exposures as well as other image artefacts such as radiation exposure and hits from cosmic rays etc.
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Old 10-09-2009, 14:11
jarwyn
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Just had a look at the new HUBBLE images on the bbc website today - amazing.

But one question bothers me, if the images are so good ... why can't they point it at MARS and determine if there is water there once and for all?

Or am I missing something obvious (I'm not an astronomer).
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Old 10-09-2009, 14:36
njp
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But one question bothers me, if the images are so good ... why can't they point it at MARS and determine if there is water there once and for all?
We already know there is water vapour on mars, from spectroscopy, and geological evidence suggests that there was once flowing water. In the absence of great oceans of the stuff, that's the best a telescope can tell us.

I think what people want to know is if there is sub-surface ice. Hubble can't tell us that.
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Old 12-09-2009, 00:21
girloutofwishaw
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Mortified if I am well behind time - but was the shuttle due to arrive around now...?

Regards to all
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Old 12-09-2009, 16:48
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Bad news from the Augustine Panel who have released their summary findings on NASA's future - $3 Billion annual budget shorfall if NASA are to continue with meaningful manned exploration. Reading between the lines it's the end of Constellation as we know it - Ares is as good as dead but Orion might live on. Shuttle program will be extended and they'll try to bodge something out of the 30 year old shuttle technology. Shocking! Forget about moon landings any time soon and Mars looks further away than ever.

http://news.bbc.co.uk/1/hi/sci/tech/8245409.stm

Only good thing is that the ISS might live for a bit longer allowing further expansion.
I think it's also worth having a look at the actual report here http://www.nasa.gov/pdf/384767main_S...0-%20FINAL.pdf. It's only a 12 page summary report and it doesn't take all that long to read.

Reading between the lines, it's clear that some panel members were OK with just having make do with Soyuz trips to the ISS while the Shuttle replacement is under construction but then again the option of a few extra Shuttle flights was mentioned - it looks like they haven't made their mind up on that aspect.

The report is also ambiguous about thesize of the Orion crew vehicle (bigger conical Apollo capsule) and which launch vehicles to develop. They should, I feel, proceed carefully on these issues.

The one thing that ramps up the costs and adds to delays is to start messing around and changing project parameters. That is the bane of many computer and defence projects.

The report seems quite positive about exploring the Moon, Mars and nearby asteroids and they even mention the possibility of visiting one of Mars' moons.

Overall then, this document strikes me as just setting out the options that this committee will consider and does not yet come to any firm conclusions. Neither this report nor the cover letter that goes with it [http://www.nasa.gov/pdf/384974main_T...-%20FINAL.pdf] states when the final report is likely to be issued - again more potential delays and resultant costs.
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Old 15-09-2009, 11:14
Assa2
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I think it's also worth having a look at the actual report here http://www.nasa.gov/pdf/384767main_S...0-%20FINAL.pdf. It's only a 12 page summary report and it doesn't take all that long to read.

Reading between the lines, it's clear that some panel members were OK with just having make do with Soyuz trips to the ISS while the Shuttle replacement is under construction but then again the option of a few extra Shuttle flights was mentioned - it looks like they haven't made their mind up on that aspect.

The report is also ambiguous about thesize of the Orion crew vehicle (bigger conical Apollo capsule) and which launch vehicles to develop. They should, I feel, proceed carefully on these issues.

The one thing that ramps up the costs and adds to delays is to start messing around and changing project parameters. That is the bane of many computer and defence projects.

The report seems quite positive about exploring the Moon, Mars and nearby asteroids and they even mention the possibility of visiting one of Mars' moons.

Overall then, this document strikes me as just setting out the options that this committee will consider and does not yet come to any firm conclusions. Neither this report nor the cover letter that goes with it [http://www.nasa.gov/pdf/384974main_T...-%20FINAL.pdf] states when the final report is likely to be issued - again more potential delays and resultant costs.
If they can continue to develop Orion & Ares in the mean time then the longer the panel takes to consider things, the less likely they are to turn their back on the Constellation program as a whole. I suppose they may delay developing Ares V for a few years to save costs and go with the Ares I / Orion as a stop gap to get back to the ISS and low earth orbit missions. They can then develop Ares V and the other bits of kit they need for Moon/Mars/Deep Space missions later in the next decade for missions in the 2020's.
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Old 15-09-2009, 17:35
MisoSoup
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Hullo space fans

I thought you might like to see these pictures from the 2009 Astronomy Photographer of the Year contest

http://www.telegraph.co.uk/science/p...n-winners.html

I love picture number 7, of the Moon, Jupiter and Venus
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Old 19-09-2009, 10:58
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The first images have just come in from the ESA's Planck Telescope to look into the nature of the early universe by studying the residual cosmic microwave radiation.

There's more on the story here http://news.bbc.co.uk/1/hi/sci/tech/8260711.stm and it's good to see that this space telescope is functioning well.
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Old 26-09-2009, 15:15
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Last week saw the reports of water being present in lunar soil in the ratio of 1 litre of water per cubic metre of lunar soil. The water is in the form of a thin film around the lunar soil particles.

We have India's Chandrayaan lunar satellite to thank for this discovery and more on the story here http://news.bbc.co.uk/1/hi/sci/tech/8272144.stm. Certainly, there does appear to be potentially useful amounts of water there for future lunar colonists even though that soil is far drier than the worst of Earth's desert soils.

That report was given a high priority by the news channels and radio station. However, another water story got far less publicity and I think it's more important.

Scientists studying impact craters using instruments aboard NASA's Mars Reconnaissance Orbiter have come across water ice which has been revealed by crater impacts http://www.sciencemag.org/cgi/conten.../325/5948/1674.

Although it is early days, these initial results could indicate that water ice is pretty wide spread below the Martian surface in large amounts - a bit like arctic permafrost. It should make it easier for any future Martian explorers as it means that there is a readily available source of water and oxygen there.

That currently solid ice could, millions have years ago, have been responsible both for some of the liquid water flow patterns on the Martian surface and for a thicker atmosphere in the form of increased levels of water vapour.
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Old 03-10-2009, 15:13
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It looks like hell-planet Venus really did have much greater amounts of water present in its past. Measurements from the Venus Express probe have shown that there is a disproportionate ratio of deuterium oxide - heavy water - in the remaining amount of atmospheric water vapour.

The implications that there was much more ordinary light water present eons ago but that it was lost to to climate change, being stripped away by the solar wind and by UV dissociation. More on this story here: http://www.astronomynow.com/news/n0909/16venus/
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Old 06-10-2009, 00:22
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Absolutely stunning hi-res photo mosaic of the Galactic Centre Region. Drag the box and zoom in. So many stars, it's breathtaking: http://astrosurf.com/sguisard/Pagim/GC.html
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Old 06-10-2009, 16:38
Ricardodaforce
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Absolutely stunning hi-res photo mosaic of the Galactic Centre Region. Drag the box and zoom in. So many stars, it's breathtaking: http://astrosurf.com/sguisard/Pagim/GC.html
That's a good link Roy, cheers. Of course, I've seen thing you people wouldn't believe....
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Old 06-10-2009, 17:03
HenryGarten
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That's a good link Roy, cheers. Of course, I've seen thing you people wouldn't believe....
Welcome back. I see you have been away for a while!
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Old 06-10-2009, 17:04
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That's a good link Roy, cheers. Of course, I've seen thing you people wouldn't believe....
just the one thing then?
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Old 06-10-2009, 17:10
benny1982
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This is only my theory but many also agree is that outer space itself alone just goes on for ever and ever and ever and ever. If you went in a super fast spaceship downwards, upwards or along beyond the universe you would just keep going for ever and ever and ever. (providing the spaceship has an electric making generator that would keep it going and going forever)
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Old 07-10-2009, 08:15
Ricardodaforce
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Welcome back. I see you have been away for a while!
Cheers H.

This is an interesting story. Massive ring discovered around Saturn.
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Old 07-10-2009, 08:48
Assa2
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Brilliant stuff! Just goes to show there's still lots to discover in our own back yard.

Good to have you back, Ricardo.
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Old 09-10-2009, 09:52
HenryGarten
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LCROSS due to impact the moon in in just over 150 minutes.

See http://news.bbc.co.uk/1/hi/sci/tech/8297811.stm
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Old 09-10-2009, 12:24
boxx
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LCROSS due to impact the moon in in just over 150 minutes.

See http://news.bbc.co.uk/1/hi/sci/tech/8297811.stm
Watching on Nasa TV now. 10 minutes to impact!!
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Old 09-10-2009, 12:28
mirandashell
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Now 5 minutes!
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