SUMMARY: One of the instruments tuned into Deep Impact is NASA's Swift satellite, normally designed to detect and analyze gamma ray bursts. Swift has been watching the expanding debris cloud, and detected increasing numbers of X-rays every day. This has enabled scientists to accurately measure the total amount of material released. So far, it appears that several tens of thousands of tonnes of debris were blased off the comet into space; enough to bury a football field under 9 metres (30 feet) of dust.

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This is interesting, the total amount of fine dust released by Deep Impact is enough to cover a the Penn State football field about 9 meters deep, but the crater is about (by some estimates) ten times the surface area of a football field. This means the dust constitutes about one meter of whatever the depth of the crater is.

We don't know what the depth of the crater actually is, but you can be sure it is much more than one meter. So what's the rest of the excavated material? I'm curious to see a quantatative measurement of the Hydroxyl Ions observed so as to get an estimate of the ice that was vaporized, or released and sublimated in the sunlight.

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Forming opinions as we speak

There's already infrmation about the amount of water detected, and not just OH, see here, it actually shows an initial decrease in the amount of water vapour. Other comments: see the EU thread.
And the light that formed wasn't all sunlight eihter.

Cheers.

Thanks for the link, VanderL.

However, I looked at the figure with the four measurements here, Water Vapor Measurements.

Perhaps others can see useful information there, but frankly I was very disappointed.

I expected quantitative information on the major comet constituents from NASA's much celebrated Deep Impact on the 4th of July .

Are there other links which give relative amounts of

a.) Rocky material
b.) Water, and
c.) Hydrocarbons

in the comet?

I would hate to see the Deep Impact event go the way of the Genesis Mission and fade from view with nothing but empty promises.

With kind regards,

Oliver
http://www.umr.edu/~om

Thanks for the link. You are right that the lack of a scale on the Y-axis really doesn't help us much as far as water vapour measurements go.

BTW, you've expressed your disappointment about the Genesis data quite a few times recently. Perhaps the thing to do, is start a thread in "Space Exploration" about the Genesis data, similar to the WMAP Year Two data thread. This would concentrate the discussion about this topic better than just leaving a lot of loose complaints in other topics.

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Forming opinions as we speak

Thanks for the suggestion, Anton.

Would a thread in "Space Exploration" about the Genesis data bring more pressure on NASA for change than "loose complaints" in other threads about the repeating discrepancy between their PR for each mission and the lack of experimental data ?

With kind regards,

Oliver
http://www.umr.edu/~om

I don't know (my guess is yes), but it would certainly help to both focus the conversation, and keep the other thread on-topic. I suspect that there is some support for your general concern about the slowness of the publishing of the Genesis results. The thread on the WMAP Year Two data may or may not have had an impact, but it has been a pretty thoughtful discussion bringing focus to the issue, and resulting in several congressmen receiving letters, whereas loose sniping did nothing.

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Forming opinions as we speak

Fantastic results. Can anybody tell me why copper was chosen as the material for the impactor?

Thanks for the link, VanderL.

However, I looked at the figure with the four measurements here, Water Vapor Measurements.

Perhaps others can see useful information there, but frankly I was very disappointed.

I expected quantitative information on the major comet constituents from NASA's much celebrated Deep Impact on the 4th of July .

Are there other links which give relative amounts of

a.) Rocky material
b.) Water, and
c.) Hydrocarbons

in the comet?

I would hate to see the Deep Impact event go the way of the Genesis Mission and fade from view with nothing but empty promises.

With kind regards,

Oliver
http://www.umr.edu/~om [/b][/quote]
Hi Oliver,

There is some information on what has been found thusfar this website contains all publicly available images/spectra. I share your concern about the sparsity of available data. Of course the Deep Impact team will make sure Nature and Science publications will come from the data. This is only natural, but it is a frustrating wait for additional information.

I'm curious why you think the water data are disappointing, the curves show all that is needed, the peak's area under the curve is the amount of water vapour, pre-impact and post-impact. The difference is the increase in water vapour by the impact, and it is almost non-existent. So, one conclusion can be made: comets are not "dirty snowballs".

Another finding is that no complex organic molecules were detected (as were found in comet Hyutake).

Cheers.

Copper was chosen as the impactor material so that it would not chemically react with the comet's surface (that would muddy up the data presumably).

Oliver have you seen this article?

This quote says it all:
Cheers.

Thanks, VanderL.

That's interesting. Hydrocarbons are made of elements #1 and #6. Water is made of elements #1 and #8. Rocks are made mostly of elements #8 and higher.

With kind regards,

Oliver
http://www.umr.edu/~om

Thanks, VanderL.

That's interesting. Hydrocarbons are made of elements #1 and #6. Water is made of elements #1 and #8. Rocks are made mostly of elements #8 and higher.

With kind regards,

Oliver
http://www.umr.edu/~om [/b][/quote]
And silicates?

Cheers.

Silicates are abundant in many rocks. Made of elements #8 and higher.

Oliver
http://www,umr.edu/~om

The comet discussion on this forum so far has been dominated by three individulals (4, including myself, but I'm not really important enough to be counted into the mix).

All I can say is that this exploration has produced benefits beyond previous understandings. Unless this experiment had occurred at all, we would not have had the opportunity to discuss this matter to begin with. Let us remember that, far all the importance given to theory, nothing trumps actual observation and interpretation. We can all stand here and trunp "Electric Universe" over "Plasma Universe" over end-all. But, in the reality we exist in today, none of these things cannot be validated without good-old-fashioned exploration.

Nothing shakes a "theory" more than looking the facts square in the face.

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The funny thing about Newton is that he wasn't proven wrong; he was proven inaccurate.

It was his danged inability to throw apples at relativistic speeds toward the ground.

The comet discussion on this forum so far has been dominated by three individulals (4, including myself, but I'm not really important enough to be counted into the mix).

All I can say is that this exploration has produced benefits beyond previous understandings. Unless this experiment had occurred at all, we would not have had the opportunity to discuss this matter to begin with. Let us remember that, far all the importance given to theory, nothing trumps actual observation and interpretation. We can all stand here and trunp "Electric Universe" over "Plasma Universe" over end-all. But, in the reality we exist in today, none of these things cannot be validated without good-old-fashioned exploration.

Nothing shakes a "theory" more than looking the facts square in the face. [/b][/quote]
Couldn't agree more, observations are the way forward, well said dave_f.
I know some people are relying more on math and the theories they produce, but I'm more an observationalist, I want to see data first.

Cheers.

Thanks for the link, VanderL.

However, I looked at the figure with the four measurements here, Water Vapor Measurements.

Perhaps others can see useful information there, but frankly I was very disappointed.

I expected quantitative information on the major comet constituents from NASA's much celebrated Deep Impact on the 4th of July .

Are there other links which give relative amounts of

a.) Rocky material
b.) Water, and
c.) Hydrocarbons

in the comet?

I would hate to see the Deep Impact event go the way of the Genesis Mission and fade from view with nothing but empty promises.

With kind regards,

Oliver
http://www.umr.edu/~om [/b][/quote]
Ouch Oliver,

I think your suspicions that the Deep Impact might fade from view are correct if this article as anything to go by.

I hope this report is a "one off' that won't reflect the future publications. But if I read this article correctly, nothing of any importance or relevance was learned from the DI mission. Nothing really happened, the "comet goes back to sleep" and so should we!

From the article:
I wonder what all that celebrating was about after the impact, I read this as "the results don't match our model(s), forget about this mission, we'll need a drill to get to where the ice surely must be".

Then I suggets you look at the images of the NOT telescope at El Roque de los Muchachos observatory (La Palma, Spain). You can find these images at this website , if that aren't any new jets (well the old ones are also there, that makes it an almost lie?) than I'll buy a hat and eat it.

See? Nothing happened, everything was as expected and the work that has to be done will take a long, long time. Gee, am I disappointed?

I wonder what will happen to the crater contest, maybe they'll organize a lottery and make sure the scientists involved can't enter the competition.

Cheers.

I think this line is telling. Granted it is only a science journalist writing a summary, but the implication is NOT that we are done and nothing happened, but rather that the comet is mostly back to normal, and that the scientists have A LOT of work ahead of them to understand the results from this new dataset.

I will grant you that they will not explore many far-out alternative explanations for the observations. I expect most studies to assume that the comet was formed 4.6 billion years ago of material in the disk about the distance that Saturn is now, and that this object has been through the inner Solar System losing its volatile materials for millions of years.

It does sound like the initial story-line here is that Deep Impact slammed into a layer of dust so thick that the rest of the comet was unperturbed. Concerning the new jets observed in the NOT and WHT images from the Canary Islands, I'd like to see more about them. They seem not to be active now, ten days later. I wonder if they were artifacts of the impact spray only. Again, I'd like to know more about them.

__________________
Forming opinions as we speak

I think this line is telling. Granted it is only a science journalist writing a summary, but the implication is NOT that we are done and nothing happened, but rather that the comet is mostly back to normal, and that the scientists have A LOT of work ahead of them to understand the results from this new dataset.

[/b][/quote]
Yes Antoniseb, and my, admittedly cynical, view is that the rest of the story shows that nothing really important happened, meaning no conclusions will be made that "jeopardise" the dirty snowball model.

Well, this part of the story is something that is completely untestable for the moment (and for the foreseeable future), so that assumption will remain standing for a long while. What is clear from the data however, is that not even an "icy dirtball" can form jets when covered in a thick layer of dust. The findings directly contradict the snowball model, a conclusion no one has dared to venture yet (at least not people who are seen as authorities ).

Yeah, right, I'm not sure if you read the "defence' mechanism I mentioned in the EU thread, but this is definitely one of them. Did you look at the images and explanation of the NOT people? They are very clear; existing jets became stronger and several new jets emerged (15 hours post-impact). You can even see them with you own eyes. I hope you're not prepared do dismiss those findings?

Cheers.

Dismiss them, no, I am very curious about them. From what I've seen so far these new jets appeared and disappeared. I'd like an explanation or hypothesis at least. We are all looking for the detailed time-line of what was observed by what instruments when. The NOT & WHT jets are certainly part of the overall picture.

I am also interested in knowing about how jets can form, given the thick