'Cosmos' Recap: Halley's Comet History and 4 More Amazing Facts from Episode 3

The newest episode of "Cosmos: A Spacetime Odyssey" dove into all things big and small including the history of modern science.

Aired Sunday night (March 23), the third episode of the reboot of Carl Sagan's beloved TV show "Cosmos: A Personal Voyage" explains how knowledge of the workings of gravity, comets and the solar system changed the way that humans look at the stars and science.

"These are the snows of yesteryear," Tyson said of the Oort cloud. "Drifting mountains of ice and rock, the preserved remnants of the birth of the solar system."

AAAAARRRRGGGGHHHHH!!!!!!! We've visited three comets, slammed a 643 pound mass of copper into one, and flown by several more including Halleys. . . NOT ONCE has any ice or water been observed or found. None. Zip! NADA! The closest was the observation of some hydroxyl radicals (OH) released when the Deep Impact probe impacted Comet 9P / Tempel in amounts less than 1/100th the amount expected for H₂O. Yet there was no water at all. In fact, except by orbit, every comet was essentially indistinguishable from every asteroid we've visited, flown by, or probed.

But her is Tyson, nine years later, ignoring all the results of those fly-bys, touch-downs, and the impact and STILL talking about "ice and rock mountains!" That theory has been FALSIFIED! In spades!

I expect current science from this "update," not a rehash of discredited, old theories.

I liked it. I already knew a lot about Newton, but not that much about his relationship with Halley, although I knew it was through Halley’s efforts that the Principia came into being. I also new about his spat with Hooke, and there is more detail to be known about the technicalities of their correspondence. I think Newton let his guard down at one point, and Hooke caught him in an error, which peeved Newton no end, needless to say. I think the dramatisation was largely correct, though.

I noticed they used a cannon in their animation of Newton’s illustration showing the ballistics of an earth orbit. Newton referred to a “projected stone” and hypothesized an airless earth for the sake of the example, so he was being very abstract. He was connecting the IDEA of ballistics to the IDEA of celestial motion. whether he had any notion that this connection would become actual, I don’t know.

I noticed that when the host enumerated the various omens attributed to comets, he mentioned several African tribes, but here as previously, he showed traditional Cro-Magnon, i.e. European, cave man types to illustrate “our ancestors”. I suppose compromises were made.

I thought he could have said more about the Principia, i.e. that it was patterned after Euclid’s Elements. He could have done a “Gee whiz” zoom through of some of the diagrams, too. The work itself is a marvel to behold.

I suppose he had to fight just to put it on the table.

As before, I thought the space animations were cliched and dismal. It amazes me that critics have called them mind-boggling, etc. We’ve been saturated with that stuff, and it is by no means “realistic” !

The cartoons have been the surprise attraction for me.

The water WAS NOT found. In the original data, they reported 1/100th expected amount of water vapor and ice. They saw hydroxyl radicals (OH) . . . And only a small fraction of water molecules. In later years, analysis of other data they claim to have found more "water" signature in the InfraRed of the blast.. This they have confabulated this into water and then ice. OH and Water have the exact same IR signature to an InfraRed sensor. It IS THERE. But it isn't what they think it is. Their own observations prove it.

"In the Deep Impact data we're essentially watching water molecules form and then dissipate right in front of our eyes," said (Dr. Jessica M.) Sunshine, who said her first reaction to the M3 data was skepticism.

The "water" was seen via an InfraRed Sensor only in a "collimated" core of the blast rising rapidly in a 90° straight up from the center of the impact, which is a highly unlikely location for the water to come from, especially at over 1000° C, but that was the only place it was seen. This is "highly unlikely" because it would be the area with the greatest impact, damage, penetration, bore, inertia to ejecta, etc. The rest of the ejecta of dust and rock was ejected at low to high angles (15° up to 75°) but no water or OH radicals were observed in those low angle particle ejecta.more importantly, the water/hydroxyl radicals observed in the collimated jet were described as "pure, not mixed with other ejecta, rock, or other cometary materials. . . virgin, just newly formed water and hydroxyl." Note Sunshine's quotation above! ". . . essentially watching water molecules form and dissipate right in front of our eyes."

What the Deep Impact collision did was not uncover any existing water or ice in some deeply buried "pocket" on Tempel 1—water that just coincidentally ejected in a chemically pure collimated jet of superheated steam from only the exact center of the impact point—it instead, by initiating an electrical discharge between the positively charged impact probe and the VERY highly negatively charged comet, evinced by the double electrical arc just before impact, then vaporizing tons of rock freeing up lots of free Oxygen in a charged environment, allowing the Hydrogen Ions in the solar wind to combine in the hot plasma column of the discharge with that newly freed Oxygen to form pure virgin OH and some H₂O which almost instantly dissipated— just exactly as the scientists described observing.

Incidentally, all this can and has been easily recreated in the laboratory,

Every other comet we've visited has been dry as a bone.

Other comets defy convention: Shoemaker-Levy 9 exploded when it encountered Jupiter’s magnetosphere, and the pieces did not expel the volatile compounds astronomers expected to see. Deep Space 1 flew by comet Borrelly in 2001, finding it hot and dry instead of cold and wet. The Stardust mission to comet Wild 2 found a great deal of dust, but no trace of water could be found on its surface.

Ordinary asteroids can, occasionally, when approaching the sun, suddenly take on the attributes of comets:

According to a recent press release, on December 11, 2010 asteroid 596 Scheila became much brighter than previously observed, forming a large C-shaped coma. The Swift space-based observatory did not find water vapor thought to be “normally” associated with comets. Instead, two dusty plume-like tails trailed behind the asteroid, subsequently fading over the next several months.

Asteroid 596 Scheila in her Comet Costume!

A total of 5 million kilograms (11 million pounds) of water[36] and between 10 and 25 million kilograms (22 and 55 million pounds) of dust were lost from the impact.[34]

By the way, since we have no good photographs of Tempel 1 actual ejecta, those numbers are wild ass guesses. Said "water" was glimpsed as a self-illuminated spectrum line for just a split second or two in the flash, then dissipated. Deriving a quantitative figure is highly speculative. . . I, for one, would love to know how Dr. Sunshine picked that number out of the air. . . Figuratively.

That's about 1.3 million gallons. Hmmmm something doesn't smell right! That's about FOUR ACRE FEET of water!!! Now I know that number was pulled out of someone's nose! An acre is 235 feet in diameter. . . Enough water to cover a crater 235 feet in diameter four feet deep in water. . . But, but, but. The crater ain't that big, not by a very long shot!!!!

The blurry dimple in the center of the yellow circle is the crater made by the Deep Impact projectile. . . Note, it's not the dark one at the ten-eleven o'clock position, but right in the center. The yellow circle is about 100 meters in diameter

If the yellow circle is ~100 meters or 110 feet times 3 equals ~330 feet! then that little tiny dimple Deep Impact crater is 1/20 of that in diameter! Let's be generous and make it 1/10th or 33 feet in diameter. Assuming a hemispherical crater, the volume of material is calculated by volume = 1/2 x (4/3) x π x 1/2 33ft³. 9,408 cubic feet vacated from that crater. . .

Oh oh. . . There are 7.48 gallons in a cubic foot of water, and somewhat less in crystalline ice. . . but let's go with water. 7.48 times 9,408 cubic feet equals 70,372 gallons of H₂O. . . Convert to kilograms. . . 266,387 kilograms of water, if the ENTIRE crater were full of only water!

Where did the rest of the 4,733,613 kilograms of water come from that Wikipedia claims blew out from that crater, not to mention the 10 to 25 million kilograms of OTHER ejecta that was somehow Stuffed into that hole. Somebody's exaggerating. . . Or should we say lying?

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