Deep Impact Predictions

maxtheknife · Jul 9, 2005

Fantastic posts, Dmjspace. I've been enjoying them, thanx <img src="/images/icons/smile.gif" />

dmjspace · Jul 9, 2005

Maxtheknife, Thanks. Aside from the couple of kneejerk pronouncements claiming the death of the EPH at the beginning of this thread, it's actually remained quite civil here. Maybe we'll all <gasp /> learn something from having a normal conversation, unfortunately a rarity in the message boards. Some might ask, "Who cares if it's a snowball or a dirtball?! It's 80 million miles away!" But it's important to know because, if this is a piece of a planet, it means that planets can occasionally meet an explosive demise. Last time I checked, we were all living on one. Yes, we may end up blowing ourselves up anyway in a nuke-fest, but I guess I'm not *that* much of a cynic. I hope we stick around long enough to solve some of these cosmic mysteries...

a_lost_packet_ · Jul 10, 2005

dmjsapce - Maybe we'll all <gasp> learn something from having a normal conversation, unfortunately a rarity in the message boards. Thats the real goal here. It's not to prove or disprove someone's idea, but to find out what the evidence actually shows. Cosmology has been called the biggest "non-experimental" science. Deep Impact certainly qualifies as an experiment which can test a hypothesis. However, just because the expected results aren't all there doesn't mean that the entire hypothesis has to be thrown out. It may just need some modifications that come to light given the experimental results. I, like most people on these boards, am very interested to see what the final results are. I can only hope that the ejecta clears somewhat before the end of the flyby craft's mission life. I really want to see that darn crater! <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

vogon13 · Jul 10, 2005

I suspect the freshly exposed ices at the bottom of the new crater are going to outgas and obscure the new crater until the comet nucleus moves away from the sun. Several months from now. <div class="Discussion_UserSignature"> TPTB went to Dallas and all I got was Plucked !!So many people, so few recipes !!Let's clean up this stinkhole !! </div>

a_lost_packet_ · Jul 10, 2005

It's definitely possible. If it's any longer than a few more weeks I don't think the flyby's cameras are going to be able to get us any good pictures. Another problem is that if it is outgassing, the new crater may be enlarged by the gradual sublimation. Then, it'd be off to the drawing boards to make estimates on how much material was ripped away by outgassing versus how much was initially removed by the impact. Considering the plume already produced, the material must be very fine and the below-surface material not very dense. Hopefully, this won't impact the size of the crater very much as it plumes. <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

dmjspace · Jul 10, 2005

packet said: Considering the plume already produced, the material must be very fine and the below-surface material not very dense. Hopefully, this won't impact the size of the crater very much as it plumes. Yes, scientists are now saying that there was a deep layer of very fine dust on the surface of Tempel. That creates a lot of problems in interpretation. The dust scatters a lot of light, potentially creating the illusion of an explosion larger than that which actually occurred. That much dust also would potentially slow (if only minutely) the probe's impact. It's going to take a while to piece together what happened here. What's important, however, is that the EPH expects a regolith (a loose layer of dust over rock) on comets and asteorids. I'm not sure if standard models expect any significant regolith. Actually, I've been informed that the standard model did NOT expect regolith because it assumes high velocity impacts would have ejected any such dusty covering. But in 1991 we got a closer look at Gaspra, and it was covered with debris. The EPH, on the other hand, expects a layer of loose debris (carbon ash from the explosion) covering asteroids and comets. If Tempel is basically an asteroid covered with dust, then the plume must have been composed mostly of rock particles (with some ice mixed in). But the fact that we are not seeing a spewing geyser of ice from the "snowball" inside presents some problems for the standard model. NASA expected high velocity outgassing jets of "prisitine" ice. Where are they?

dmjspace · Jul 10, 2005

stevehw33 said: Its NOT a belief. It's a fact. Comets really are composed of mostly water ices, some rocky materials, CO2 and a few other lesser substances. What you've stated is a belief. It's a model. Why do you think NASA just spent $333 million to go *test* this model? You really don't know anything about spectroscopic data do you? The materials which create the coma and tail of comets are the substances released from the body of the comet by heating from the sun. Those substances have ALWAYS, when tested, shown the presence of large amounts of water. Not as much as expected were comets actually dirty snowballs. And since asteroids are 20% water by volume anyway, the presence of some water in spectra is expected in any model. Obviously, the volatile components, such as ice, are what's going to show up in the coma. The density and mass and size figures have ALWAYS shown a density of comets very nearly that of water, as well. We don't know the "density and mass and size figures" to any degree of accuracy for comets or asteroids, which is why NASA had no fewer than six different models going into the Deep Impact mission. If you'd had a decent physics and chemistry training, and reviewed even the basics of the Deep Impact mission, where the spectroscopic charts of the composition of the comet have consistently been posted, even at the website s of NASA/JPL Deep Impact section, then you'd have seen that fact. And if you were not at once the most arrogant AND ignorant (not to mention irritatingly preachy) poster at SDC, perhaps you'd have more time to spend actually looking at data rather than making assumptions based on textbook models which don't fit the data. facts, By Spectroscopic Data, well established for at l

dmjspace · Jul 10, 2005

Here's an interesting Deep Impact simulation by scientists at the Lunar and Planetary Lab. It shows the difference between NASA's preferred model (the "gravity dominated" scenario) and the EPH's expected model (the "strength dominated" scenario). In the gravity dominated simulation, the probe impacts Tempel and, rather quickly, a majority of debris (75%) falls back to the surface because gravity is the dominant factor. On the other hand, in the strength dominated simulation, the impact occurs and 50% of the ejecta continues to travel away from the comet surface, ultimately escaping the comet's gravitational influence. Given that the actual ejecta cone is still expanding outwards (implying that most of the debris is escaping from the comet), which model appears more accurate at this point? The strength dominated scenario, i.e. the EPH's favored model. Some will undoubtedly argue that the apparent expansion of the debris field is due to outgassing, and is not ejecta. That may be the case, which of course confounds things. However, if it is outgassing, that material is supposed to be almost pure ice. Unless the spectra return huge amounts of water, then we're stuck with the interpretation that the detected dust is escaping under a strength dominated scenario, and that the lack of expected ice jets simply confirms that the comet is mostly rock, not ice.

zenonmars · Jul 10, 2005

dmj: "Maybe we'll all <gasp> learn something from having a normal conversation, unfortunately a rarity in the message boards." lost: "Thats the real goal here. It's not to prove or disprove someone's idea, but to find out what the evidence actually shows. Cosmology has been called the biggest "non-experimental" science. Deep Impact certainly qualifies as an experiment which can test a hypothesis. However, just because the expected results aren't all there doesn't mean that the entire hypothesis has to be thrown out. It may just need some modifications that come to light given the experimental results." WOW !!! Sounds like my arguments about the "artificiality" investigations. All we in the "Hoagland camp" have ever asked is to do the TESTS, to verify or nullify the theory. Is it not amazing what we can learn, and how fast we can learn it, when the Space Agency we, the U.S. Taxpayers bought and paid for, decides to simply perform the test with real-time, verifiable data retrieval? This Deep Impact mission seems to be a mini - allegory of other less-than-satisfying parts of other NASA missions. As with Iapetus and the "missing" radar pings, we are all curious what the spectral data of Tempel 1 will tell us...and when. I have to agree with these words: "I, like most people on these boards, am very interested to see what the final results are." ------------------------------------------------------ Now, as for stevehw33: You no longer anger me, and your abrasive style barely amuses. " RCH is certifiable. His minions always do what the master commands." Steve? Who is your master? Do you have a NASA Master? <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> And why haven't <div class="Discussion_UserSignature"> </div>

telfrow · Jul 10, 2005

Do you have a NASA Massa? Zen: A personal note. Our differences aside, I have to tell you I find that reference offensive. While I have come to understand and accept your unique sense of humor, I am disappointed you chose to include something like that in your post. I would ask, as a favor to me, and other posters here at SDC, that you remove it. <div class="Discussion_UserSignature"> Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild. - Tennyson </div>

a_lost_packet_ · Jul 10, 2005

ZenOnMars - WOW !!! Sounds like my arguments about the "artificiality" investigations. All we in the "Hoagland camp" have ever asked is to do the TESTS, to verify or nullify the theory. Is it not amazing what we can learn, and how fast we can learn it, when the Space Agency we, the U.S. Taxpayers bought and paid for, decides to simply perform the test with real-time, verifiable data retrieval? The diference is that we knew there is a comet out there because we have verifiable evidence that it exists. There is no verifiable or even credible evidence regarding what the Hoagland camp wants tested. To devote enormous resources to performing tests on ficticious objects wouldn't be prudent. ZenOnMars - You are pathetically transparent, boringly predictable, and about as convincing as a TV evangelist. RCH? Let's try to keep the discussion slanted towards predictions of the data from Deep Impact. ZenOnMars, what do you predict we will find? <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

geos · Jul 11, 2005

How can a thick layer of dust maintain "impact" craters? The speed of collisions is not right. Maybe they are formed Electrically. Repeat after me: Thornhill was right and I posted HIS CORRECT guesses. Repeat after me: Thornhill was right and I posted HIS CORRECT guesses.

a_lost_packet_ · Jul 11, 2005

geos - How can a thick layer of dust maintain "impact" craters? The speed of collisions is not right. Maybe they are formed Electrically. Repeat after me: Thornhill was right and I posted HIS CORRECT guesses. Repeat after me: Thornhill was right and I posted HIS CORRECT guesses. ? <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

dmjspace · Jul 11, 2005

stevehw33 said: All wrong, as usual. The impact was designed to learn more about comets. We already knew they were made mostly of water. Wrong. And it's only going to get worse for your belief system as the data stream in. See, Steve, textbooks go out of date. Especially when they were based on spurious evidence in the first place. Clearly you don't believe me when I state the obvious: Deep Impact's primary mission was to find out what was *inside* the comet. So I'll let the scientists involved in making observations make it obvious: Here's a press release from July 8: Source: Harvard-Smithsonian Center for Astrophysics Title: Deep Impact Was a Dust-up, Not a Gusher Results are still coming in, but so far the scientists report seeing only weak emission from water vapor and a host of other gases that were expected to erupt from the impact site. "It's pretty clear that this event did not produce a gusher," said SWAS principal investigator Gary Melnick of the Harvard-Smithsonian Center for Astrophysics (CfA). "The more optimistic predictions for water output from the impact haven't materialized, at least not yet." Astronomer Charlie Qi (CfA) expressed surprise at these results. "Theories about the volatile layers below the surface of short-period comets are going to have to be revised," Qi said. Modern astronomers often refer to comets as "icy dirtballs" instead, reflecting the prevailing view that comets contain more dust and less ice than previously believed. Start revising your textbooks. Continuing: Deep Impact was intended to test these theories by excavating material from the comet's interior, giving scientists clues to its composition and structure. SWAS operators were puzzled by the lack of inc

maxtheknife · Jul 11, 2005

MMMmmm good! Delicious post, Dmjspace! <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> Zen... Rofl.... NASA Massa?! <img src="/images/icons/wink.gif" />

zenonmars · Jul 11, 2005

telfrow: "A personal note. Our differences aside, I have to tell you I find that reference offensive. While I have come to understand and accept your unique sense of humor, I am disappointed you chose to include something like that in your post. I would ask, as a favor to me, and other posters here at SDC, that you remove it." Yes, tel, my sense of humor does border on the strange, I'll admit. What I need to know, to comply with your request, is just what it is you find offensive with my post: the vaudvillian, Al "blackface" Jolson, stereotypical, slang "massa"? Or the notion that a government agency could have disinformational experts seeded within the various medias that comprise our "realities"? In fact I am going to change it anyway, as I can see a racist inference, even if it is a cultural antiquity. <div class="Discussion_UserSignature"> </div>

telfrow · Jul 11, 2005

It was the stereotype, Zen. As a former American History teacher whose areas of focus were - and continue to be - the American Civil War, Reconstruction and Civil Rights, maybe I'm more sensitive to the implications and meanings of those types of references than most. Judging from the fact no one else mentioned it, that may be the case. In any event, you have my sincere personal thanks for editing the post. <div class="Discussion_UserSignature"> Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild. - Tennyson </div>

zenonmars · Jul 11, 2005

Lost: "There is no verifiable or even credible evidence regarding what the Hoagland camp wants tested. To devote enormous resources to performing tests on ficticious objects wouldn't be prudent." Despite Carl Sagan's deathbed cautions to the contrary? (See "Demon Haunted World") " RCH? Let's try to keep the discussion slanted towards predictions of the data from Deep Impact. ZenOnMars, what do you predict we will find?" Gosh, in my few posts on this thread, I tried to rise to the level of most posters here, and, as dmjspace so eloquantly stated, I too believe "The only thing I'm putting my credibility in is data. Not the opinions of scientists rehashing the party line." These other distractions, this time, are not my doing! <img src="/images/icons/smile.gif" /> <img src="/images/icons/smile.gif" /> It was telfrow who brought up Mr. Hoagland back on page 10: "BTW: Funny you bring that up the day after RCH posted the same thing on his blog." stevehw33 also chimed with his attempted insult to me: on page 11: "His minions always do what the master commands. RCH is certifiable. Or one of the worst scammers around." What do I predict? <img src="/images/icons/smile.gif" /> As for the spectra data, I have no real clue. But here is my best prediction: the forthcoming NASA spectral analysis will not be properly forthcoming, if we get much at all. And if and when we hear about it, "they", the JPL/NASA/university-astronomy-insiders will be less than forthcoming with a realistic and paradigm-shattering interpretation. <img src="/images/icons/smile.gif" /> Aren't ya glad ya asked? <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

zenonmars · Jul 11, 2005

tel: "In any event, you have my sincere personal thanks for editing the post." You are most sincerely welcome! Anything for a fellow space science friend, and a good teacher as well. <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

geos · Jul 11, 2005

Thornhill predicted a VERY LARGE flare up. He got it. He was right. Lost only parrots "what everybody knows from the textbooks". The TEXTBOOKS are WRONG. DEAL WITH IT !!! I was right. I was right. I was right. I was right.

a_lost_packet_ · Jul 11, 2005

Geos - Lost only parrots "what everybody knows from the textbooks". What are you babbling about? <div class="Discussion_UserSignature"> I put on my robe and wizard hat... </div>

geos · Jul 12, 2005

Check the FACTS - I posted CORRECT guesses. Your contribution is "nil".

geos · Jul 12, 2005

I post correct guesses because I am better than you; therefore I predict I can take all of your stuff (it was the voice of God)

maxtheknife · Jul 12, 2005

Hey Zen! The gent who works for me is black.... I read him your post, Telfrow's request for removal, and your response..... He says leave it! Never forget <img src="/images/icons/smile.gif" />

telfrow · Jul 12, 2005

Max: Zen can do whatever he likes. It was a personal request, and I documented my reasons. Forget? Hardly. I wouldn't have spent the last thirty five years of my life studying the periods I noted for the purpose of forgetting. That's absurd. As for your African American employee...that's his opinion....but I think he'd have a different view of it if you used the word "massa" to describe your employer-employee relationship. Besides, I know a number of African Americans who would find the reference offensive. But this is off topic. I'd be glad to discuss it, at length, in Free Space, if you'd like to continue it there. <div class="Discussion_UserSignature"> Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild. - Tennyson </div>

Deep Impact Predictions

maxtheknife

Guest

dmjspace

Guest

a_lost_packet_

Guest

vogon13

Guest

a_lost_packet_

Guest

dmjspace

Guest

dmjspace

Guest

dmjspace

Guest

zenonmars

Guest

telfrow

Guest

a_lost_packet_

Guest

geos

Guest

a_lost_packet_

Guest

dmjspace

Guest

maxtheknife

Guest

zenonmars

Guest

telfrow

Guest

zenonmars

Guest

zenonmars

Guest

geos

Guest

a_lost_packet_

Guest

geos

Guest

geos

Guest

maxtheknife

Guest

telfrow

Guest

Similar threads

TRENDING THREADS

Latest posts

Share this page