Return of the comet: 96P spotted by ESA, NASA satellites

Return of the comet: 96P spotted by ESA, NASA satellites
The comet entered the lower right corner of SOHO's view, and skirted up and around the right edge before leaving on Oct. 30. Jupiter can be seen passing left-to-right behind the solid central disk -- called an occulting disk -- that blocks sunlight and allows SOHO to see the solar atmosphere, planets and comets. Credit: ESA/NASA's Goddard Space Flight Center/SOHO/NRL/Karl Battams/Joy Ng

The ESA (European Space Agency) and NASA mission SOHO—short for Solar and Heliospheric Observatory—got a visit from an old friend this week when comet 96P entered its field of view on Oct. 25, 2017. The comet entered the lower right corner of SOHO's view, and skirted up and around the right edge before leaving on Oct. 30. SOHO also spotted comet 96P in 1996, 2002, 2007 and 2012, making it the spacecraft's most frequent cometary visitor.

At the same time, 96P passed through a second NASA mission's view: STEREO—short for Solar and Terrestrial Relations Observatory—also watched the comet between Oct. 26-28, from the opposite side of Earth's orbit. It is extremely rare for comets to be seen simultaneously from two different locations in space, and these are the most comprehensive parallel observations of comet 96P yet. Scientists are eager to use these combined observations to learn more about the comet's composition, as well as its interaction with the solar wind, the constant flow of charged particles from the Sun.

Both missions gathered polarization measurements of the comet; these are measurements of sunlight in which all the light waves become oriented the same way after passing through a medium—in this case, particles in the tail of the comet. By pooling the polarization data together, scientists can extract details on the particles that the light passed through.

"Polarization is a strong function of the viewing geometry, and getting multiple measurements at the same time could potentially give useful information about the composition and size distribution of the tail particles," said William Thompson, STEREO chief observer at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Return of the comet: 96P spotted by ESA, NASA satellites
The comet entered the bottom of STEREO's view and crossed it diagonally before leaving on Oct. 28. Most of the corona has been suppressed in order to bring out the comet, leaving only the dynamic flow of the solar wind. Credit: NASA's Goddard Space Flight Center/STEREO/Bill Thompson/Joy Ng

Comet 96P—also known as comet Machholz, for amateur astronomer Dan Machholz's 1986 discovery of the comet—completes an orbit around the Sun every 5.24 years. It makes its closest approach to the Sun at a toasty 11 million miles—a very close distance for a comet.

When comet 96P appeared in SOHO's view in 2012, amateur astronomers studying the SOHO data discovered two tiny comet fragments some distance ahead of the main body, signaling the comet was actively changing. This time around they have detected a third fragment—another breadcrumb in the trail that indicates the comet is still evolving.

Scientists find comet 96P interesting because it has an unusual composition and is the parent of a large, diverse family, referring to a group of comets sharing a common orbit and originating from a much larger parent comet that over millennia, broke up into smaller fragments. Comet 96P is the parent of two separate comet groups, both of which were discovered by citizen scientists studying SOHO data, as well as a number of Earth-crossing meteor streams. By studying the comet's ongoing evolution, scientists can learn more about the nature and origins of this complex family.

Return of the comet: 96P spotted by ESA, NASA satellites
Observations of a third fragment indicate comet 96P is still evolving. Credit: ESA/NASA's Goddard Space Flight Center/SOHO/Steele Hill

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Nov 04, 2017
It makes its closest approach to the Sun at a toasty 11 million miles—a very close distance for a comet....Scientists find comet 96P interesting because it has an unusual composition

Clearly the religiously held belief of the dirty snowball hypothesis of comet theory has been blown out of the water by direct observation. Despite the claims of the acolyte jonesdumb.
https://youtu.be/i_pNpGSgMgI
The final nail has been set in the coffin and buried under six feet of dirt with jonesdumb's relevance on the topic.

Nov 04, 2017
It makes its closest approach to the Sun at a toasty 11 million miles—a very close distance for a comet....Scientists find comet 96P interesting because it has an unusual composition

Clearly the religiously held belief of the dirty snowball hypothesis of comet theory has been blown out of the water by direct observation. Despite the claims of the acolyte jonesdumb.
https://youtu.be/i_pNpGSgMgI
The final nail has been set in the coffin and buried under six feet of dirt with jonesdumb's relevance on the topic.


Lol. Posting youtube crap! Sorry, dear, but they found plenty of ice, plenty of dust, no rock and no electric woo. Point me to the literature if you think otherwise. I'm not wasting bandwidth watching crap from people who think Velikovsky was right! And that dinosaurs were too heavy! Lol.

Nov 04, 2017
https://smd-prod....trip.jpg

Wow! Look at all that non-electric ice!

Nov 04, 2017
The first indisputable , direct detection of H20 in any comet was made during IR observations of comet Halley from the NASA Kuiper Airborne Observatory (KAO) in December 1985.


http://adsabs.har...87..411W (1987)


When astronomers view the comas of comets spectroscopically, what they actually see is the hydroxyl radical (OH), which they assume to be a residue of water (H2O) broken down by the ultraviolet light of the Sun (photolysis)


The idiot Thornhill, 2006.
http://www.thunde...omet.pdf

Must get annoying being lied to all the time.
.

Nov 04, 2017
Simple logic and direct observation shows the dirty snowball is pre-spaceage hypothetical nonsense. No peer-review needed.
Wow! Look at all that non-electric ice!

That would be a dusty plasma, not snow moron.
The first indisputable , direct detection of H20

Electrochemistry, but not jonesdumb "electrochemistry". Remember when oxygen was found at 67P that you so conveniently ignore.
http://www.astron...g-oxygen
Must get tiresome to consistently lie jonesdumb.

Nov 04, 2017
^^^^So show me the papers that confirm your woo.

And no, it isn't dusty plasma, you idiot! It was water ice, spectroscopically resolved:
https://arxiv.org...3382.pdf

And your 'electrochemistry' doesn't work. It's woo. How are you getting H2O when the solar wind is not even reaching the comet? No O- to combine with. And nowhere near enough SW. Pure woo.
Still, if you want to continue believing the lies of a Velikovskian woo merchant, fine. Nobody else does.

Nov 04, 2017
http://www.astron...g-oxygen

You'll find that paper is not taken at all seriously by the Rosetta RPC team. Which is why it has only 1 citation. From someone writing about exoplanet biosignatures.

You can see it being discussed with one of the RPC team here:
http://www.intern...11838654

Nov 04, 2017
^^^^So show me the papers that confirm your woo.

You have already displayed how you conveniently ignore that which you do not believe, published or not. What's the point acolyte?
How are you getting H2O when the solar wind is not even reaching the comet? No O- to combine with.

Conveniently ignoring the data and explanation as usual.

Nov 04, 2017
And what happens when you hit one of Thornhill's 'rocks' with an impactor? It leaves an impossibly large crater, and excavates a shed load of solid ice grains! Whoops.

https://www.aanda...ght.html

https://pdfs.sema...12a3.pdf

Nov 04, 2017
You'll find that paper is not taken at all seriously

In other words, conveniently ignored as it neither fits with their beliefs nor do they have a viable explanation. You must have learned the same techniques as they, and your application of the technique is spot on.

Nov 04, 2017
Conveniently ignoring the data and explanation as usual.


What data? I dealt with the data here:
http://www.intern...11837709

Nov 04, 2017
You'll find that paper is not taken at all seriously

In other words, conveniently ignored as it neither fits with their beliefs nor do they have a viable explanation. You must have learned the same techniques as they, and your application of the technique is spot on.


Nope, as a mission scientist on that page agreed, the mechanism is highly unlikely, and the numbers are way out.
http://www.intern...11837709

These people are not au fait with cometary environments. It was a bad paper.

Nov 04, 2017

And what happens when you hit one of Thornhill's 'rocks' with an impactor? It leaves an impossibly large crater, and excavates a shed load of solid ice grains! Whoops.

Whoops is right! How did it align with the predictions? The predictions failed miserably. And that "impossibly large crater" was so conveniently "filled up" and was "hidden" with debris that conveniently fell right back into place...LOL!

https://www.newsc...s-story/

Lest we not forget/ignore the prediction by Thornhill there would be a flash prior to impact, as was observed. Still, conveniently ignored.

Nov 04, 2017
Nope, as a mission scientist on that page agreed, the mechanism is highly unlikely, and the numbers are way out.
http://www.intern...11837709

As has been pointed out repeatedly, that which does not agree or is explainable by your failed theories is conveniently ignored and marginalized. It's religious in nature, and a pathetic display of scientific method. Clearly these people are protecting their relevance which is soon to be realized is none.

Nov 04, 2017
Nope, as a mission scientist on that page agreed, the mechanism is highly unlikely, and the numbers are way out.
http://www.intern...11837709

As has been pointed out repeatedly, that which does not agree or is explainable by your failed theories is conveniently ignored and marginalized. It's religious in nature, and a pathetic display of scientific method. Clearly these people are protecting their relevance which is soon to be realized is none.


No, idiot, I'll repeat; the mechanism is highly unlikely, and the numbers are way off. Do what I did. Read the paper, figure it out for yourself. Show me where I, and a plasma astrophysicist, are wrong.

Nov 04, 2017
And as of yet, not a comment on the utter failure of the predictions or the successful predictions by Thornhill.
The impact was much more energetic than presumed by mission scientists, Thornhill predicted the energy to exceed that of a simple physical impact. Thornhill- 1; Mission- 0
Sized, volume, and characteristics of the dust plume. Thornhill-2; Mission- 0
Surface geology, open your eyes. Thornhill- 3; Mission- 0
New collimated jets, check. Thornhill- 4; Mission- 0
It goes on, but what's the point, you will ignore and marginalize.

Nov 04, 2017
No, idiot, I'll repeat; the mechanism is highly unlikely

But there is the O, and as the direct data from Rosetta shows there are plenty of electrons present... The M.O., ignore, marginalize, and obfuscate. You're a pro!

Nov 05, 2017
And as of yet, not a comment on the utter failure of the predictions or the successful predictions by Thornhill.
The impact was much more energetic than presumed by mission scientists, Thornhill predicted the energy to exceed that of a simple physical impact. Thornhill- 1; Mission- 0
Sized, volume, and characteristics of the dust plume. Thornhill-2; Mission- 0
Surface geology, open your eyes. Thornhill- 3; Mission- 0
New collimated jets, check. Thornhill- 4; Mission- 0
It goes on, but what's the point, you will ignore and marginalize.


Sorry, where were his calculations for this? And why didn't he tell you lot that the crater was waaaaaay too big to have been made in rock? And why not tell you that a shed load of ice grains were
ejected by that impact? That killed his rocky comet nonsense dead. That's why.

Nov 05, 2017
Of all the spectra likely to be recognized and differentiated from any other, water has to lead the list.

It's rank stupidity to claim that water spectra "aren't water." It's like calling a giraffe a "giraffe shaped thing with long legs, a long neck, and spots all over it."

Nov 05, 2017
No, idiot, I'll repeat; the mechanism is highly unlikely

But there is the O, and as the direct data from Rosetta shows there are plenty of electrons present... The M.O., ignore, marginalize, and obfuscate. You're a pro!


And there is nowhere near enough H2O+. As required by their mechanism. As I demonstrated on ISF. By many orders of magnitude. And what is going to happen to a positive ion, or an electron, for all I care, when it hits a piled up magnetic barrier? Just going to pass through it, is it? Sorry, but such things would be observed, and they aren't. Do the maths. There was a recheck of the Halley data, where they also now see O2. Have a look at what they found in the cavity. And, again, do the maths. After you've figured out which way everything is headed within that cavity. Like I said, it was a poor paper.

Nov 05, 2017
Just to simplify this for those who may be struggling:
The authors of the paper that CD linked propose a mechanism involving accelerated H2O+ ions striking the comet. The numbers they give are a flux at 2 AU of 3 x 10^9 -3 x 10^11 m^2/s. This agrees with a paper they quote from Nillson et al:
Evolution of the ion environment of comet 67P/Churyumov-Gerasimenko
https://www.aanda...-15.html

It is noteworthy that the flux of water ions impinging on the nucleus is frequently of a similar order of magnitude as that of the solar wind. At times, it is even higher than a typical solar wind flux and reaches above 10^11  m-2 s-1.


So, the area of the comet exposed to the SW is ~ 10 km^2 = 10^6 m^2 = ~ 10^17 impacts per second. If each one creates an O2 molecule, that is the number created. O2 = ~ 5% of H2O production. At max that = ~ 200 l/s. = 7 x 10^27 mol/s.

Houston, we have a problem. Anybody see what it is?

Nov 05, 2017
This is a snow pile is it white and icy? Why not? https://www.bosto...ont-melt

Nov 05, 2017
And why didn't he tell you lot that the crater was waaaaaay too big to have been made in rock?

jonesdumb likes to revise history to fit his religious like beliefs. Even wiki and it's questionable reporting disagrees with jonesdumb. From wiki reporting on the predictions of comet scientists;
Photographs taken by the spacecraft showed the comet to be more dusty and less icy than had been expected. The impact generated an unexpectedly large and bright dust cloud

It goes on to say;
Initial results were surprising as the material excavated by the impact contained more dust and less ice than had been expected. The only models of cometary structure astronomers could positively rule out were the very porous ones which had comets as loose aggregates of material. In addition, the material was finer than expected; scientists compared it to talcum powder rather than sand.

TBC...

Nov 05, 2017
Con't
Other materials found while studying the impact included clays, carbonates, sodium, and crystalline silicates which were found by studying the spectroscopy of the impact.[15] Clays and carbonates usually require liquid water to form and sodium is rare in space.

But where is the liquid water? These substances were likely created by the discharging that occurred. Anyways...
Let's talk about the crater, when one compares the simulations of the impact;
https://commons.m...-license
And compare to the impact crater;
https://commons.m...-license
It is clear to anyone that the predictions failed miserably. The crater is minute compared to the predictions. So we know it did not hit the fabled porous comet made of loose aggregates of material. If we choose to open our eyes we can clearly see the rocks before our eyes.

Nov 05, 2017
^^^^Lol. Use any online cratering program to find out the size of a crater in rock with the DI parameters. 5 - 7m would be the answer. How big was it?

Nov 05, 2017
But where is the liquid water?

"67P from the outburst of 2016 July 03: The ejected material comprised refractory grains of several hundred microns in size, and sub-micron-sized water ice grains."... Detected with scientific instrumentations. https://academic..../4565550

Nov 05, 2017
Thornhill's prediction;
"The impact/electrical discharge will be into rock, not loosely consolidated ice and dust. The impact crater will be smaller than expected."
Which was confirmed by observation.
Use any online cratering program to find out the size of a crater in rock with the DI parameters. 5 - 7m would be the answer.

You keep pushing the simple impact, Thornhill assumes there will be an electric discharge associated. This is how he presumed there would be an advanced flash, which was observed. It also explains the unexpected energetic display. You need to stop imparting your own narrow religious like beliefs on the event.

Nov 05, 2017
If anybody really wants to know what was modeled and predicted for the DI impact, see this:

EXPECTATIONS FOR CRATER SIZE AND PHOTOMETRIC EVOLUTION FROM THE DEEP IMPACT COLLISION
Scultz, P.H. et al.
https://pds-small...ultz.pdf

And the same author (probably the world's leading expert on impact cratering) discusses the observations here:

The Deep Impact oblique impact cratering experiment
Schultz, P. H. et al.
https://pdfs.sema...de33.pdf

There was nothing particularly surprising about this impact, or the crater size. As much as I love Celestia, it is no match for what Schultz's experiments showed!

Nov 05, 2017
But where is the liquid water?


"67P from the outburst of 2016 July 03: The ejected material comprised refractory grains of several hundred microns in size, and sub-micron-sized water ice grains."

So now water ice is liquid water? Do we need to call it "ice" and "liquid" for you now?

Nov 05, 2017
You keep pushing the simple impact, Thornhill assumes there will be an electric discharge associated. This is how he presumed there would be an ***advanced flash,****


And there wasn't one! Only on impact. Shultz had already predicted a 3 part plume. It was not unexpected. An 'electrical flash' would have been seen by SWIFT and Chandra in x-ray. It wasn't. Ergo, it didn't happen. And Thornhill is still lying. As usual.

Nov 05, 2017
CD also seems to have forgotten that MIRO on 67P measured the thermal inertia of the surface and near-subsurface. Nothing like rock.
CONSERT was an experiment whereby radio waves were sent from Rosetta through the lobe of the comet to Philae. This constrains the make up of the comet at depth. Nothing like rock.
The sound waves from the hammering of the MUPUS instrument on Philae were measured. Nothing like rock.
The density of all comets that have been measured are nothing like rock.

Nov 05, 2017
So now water ice is liquid water? Do we need to call it "ice" and "liquid" for you now?

Indeed, Ice is water as a solid! How could electrochemistry create that ?

Nov 05, 2017
Clays and carbonates usually require liquid water to form....


But don't always. Having had to dig through a bloody Wikipedia article, and then a sodding press release in the NY Times, I managed to find the paper. I'm still reading it. However, just for a start is this bit:

The presence of carbonates is provocative because, like the phyllosilicates, liquid water was thought to be required to form carbonates from CO2 in the presence of silicates. However, recent work by Toppani et al. (22) suggests that carbonates can be grown from the vapor phase in the presence
of silicates, water, and carbon dioxide vapor.

Nov 05, 2017
The paper I mentioned above is:
Spitzer Spectral Observations of the Deep Impact Ejecta
Lisse, C. M. et al
http://science.sc...5787/635 (paywalled)

Nov 05, 2017
A hammer stroke exerted on a surface dominantly excites surface waves of the Rayleigh type. By comparison of arrival times at the individual feet, we estimate the propagation velocity of these Rayleigh waves to be at least 80 m/s. With the bulk density of 533 ± 6 kg/m3 as derived from tracking Rosetta (Pätzold et al., Nature, vol. 530, 2016), this velocity translates into a shear modulus of the comet material of at least 3.2 MPa. Shear modulus scales with velocity squared, so when taking into account the formal uncertainties arising from the arrival time inversion, the shear modulus may easily be as large as 10 MPa. ***This is still low compared to solid rock or monocrystalline ice, but is compatible with highly porous materials. ***


https://agu.confe...r/118788

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