Snowstorm on a Comet

From Science@ NASA

NASA has just issued a travel advisory for spacecraft: Watch out for Comet Hartley 2, it is experiencing a significant winter snowstorm.

Deep Impact photographed the unexpected tempest when it flew past the comet’s nucleus on Nov. 4th at a distance of only 700 km (435 miles). At first, researchers only noticed the comet’s hyperactive jets. The icy nucleus is studded with them, flamboyantly spewing carbon dioxide from dozens of sites. A closer look revealed an even greater marvel, however. The space around the comet’s core is glistening with chunks of ice and snow, some of them possibly as large as a basketball.

Comet Snowstorm (snowstorm, 550px)

This contrast-enhanced image obtained during Deep Impact’s Nov. 4th flyby of Comet Hartley 2 reveals a cloud of icy particles surrounding the comet’s active nucleus. [larger image]

“We’ve never seen anything like this before,” says University of Maryland professor Mike A’Hearn, principal investigator of Deep Impact’s EPOXI mission. “It really took us by surprise.”

Before the flyby of Hartley 2, international spacecraft visited four other comet cores—Halley, Borrelly, Wild 2, and Tempel 1. None was surrounded by “comet snow.” Tempel 1 is particularly telling because Deep Impact itself performed the flyby. The very same high resolution, high dynamic range cameras that recorded snow-chunks swirling around Hartley 2 did not detect anything similar around Tempel 1.

“This is a genuinely new phenomenon,” says science team member Jessica Sunshine of the University of Maryland. “Comet Hartley 2 is not like the other comets we’ve visited.”

The ‘snowstorm’ occupies a roughly-spherical volume centered on Hartley 2’s spinning nucleus. The dumbbell-shaped nucleus, measuring only 2 km from end to end, is tiny compared to the surrounding swarm. “The ice cloud is a few tens of kilometers wide–and possibly much larger than that,” says A’Hearn. “We still don’t know for sure how big it is.”

Data collected by Deep Impact’s onboard infrared spectrometer show without a doubt that the particles are made of frozen H2O, i.e., ice. Chunks consist of micron-sized ice grains loosely stuck together in clumps a few centimeters to a few tens of centimeters wide.

Comet Snowstorm (spectra, 550px)

This plot compares the infrared spectra of particles surrounding Comet Hartley 2 (black crosses) to spectra of pure water ice grains in the laboratory (purple lines). Micron-sized grains provide the best match. What it means: Hartley 2’s snowballs are made of small bits of H20.

“If you held one in your hand you could easily crush it,” says Sunshine. “These comet snowballs are very fragile, similar in density and fluffiness to high-mountain snow on Earth.”

Even a fluffy snowball can cause problems, however, if it hits you at 12 km/s (27,000 mph). That’s how fast the Deep Impact probe was screaming past the comet’s nucleus. An impact with one of Hartley 2’s icy chunks could have damaged the spacecraft and sent it tumbling, unable to point antennas toward Earth to transmit data or ask for help. Mission controllers might never have known what went wrong.

“Fortunately, we were out of harm’s way,” notes A’Hearn. “The snow cloud does not appear to extend out to our encounter distance of 700 km. Sunlight sublimates the icy chunks before they can get that far away from the nucleus.”

The source of the comet-snow may be the very same garish jets that first caught everyone’s eye.

The process begins with dry ice in the comet’s crust. Dry ice is solid CO2, one of Hartley 2’s more abundant substances. When heat from the sun reaches a pocket of dry ice—poof!—it instantly transforms from solid to vapor, forming a jet wherever local topography happens to collimate the outrushing gas. Apparently, these CO2 jets are carrying chunks of snowy water ice along for the ride.

Comet Snowstorm (jetmodel, 550px)

An artist’s concept of Comet Hartley 2 shows how CO2 jets drag water ice out of nucleus, producing a ‘comet snowstorm.’ [larger image]

Because the snow is driven by jets, “it’s snowing up, not down,” notes science team member Peter Schultz of Brown University.

Ironically, flying by Hartley 2 might be more dangerous than actually landing on it. The icy chunks are moving away from the comet’s surface at only a few m/s (5 to 10 mph). A probe that matched velocity with the comet’s nucleus  in preparation for landing wouldn’t find the drifting snowballs very dangerous at all–but a high-speed flyby is another matter. This is something planners of future missions to active comets like Hartley 2 will surely take into account.

Comet snowstorms could be just the first of many discoveries to come. A’Hearn and Sunshine say the research team is only beginning to analyze gigabytes of data beamed back from the encounter, and new results could be only weeks or months away.

Stay tuned for updates from Comet Hartley 2.

Author: Dr. Tony Phillips | Credit: Science@NASA

 

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Steve Schaper

I suspect that the reason the ‘waist’ emits water vapor, and the two nodes have jets and snowballs has to do with the theory that these are two nuclei stuck together, and also that the ice needles and snowballs that don’t achieve the very low escape velocity, will tend to fall back towards the barycenter – the waist – and they’ve already lost most of the C02 which they might have had. As a result you have ‘snowfall’ at that location, so naturally when warmed, it emits primarily water vapor. This fallback may also explain the appearances of comet nuclei which almost have a ‘weathered’ look to them.

jack morrow

OK. So far it seems everything takes “scientists” by surprise. Hey, I’m a pilot and lots of things took me by surprise , but I never said I was a”pilot scientist” or professed what I saw or observed was a fact or made up some fiction as to what I observed. I am completely saturated with this crap. Not all comets are a dirty snowballs. What a bunch of crap! It is as stupid as saying Columbus discovered N. America after seeing the artifacts from S. America , Canada , Alaska, Greenland, etc, etc. There is more to it than a dirty snowball.

David Ball

As a young lad, I naively believed that by now (2011) mankind could rope one of these bad boys and space-based robotic mining units retrieve and separate all minerals and water.

David Ball

Oh and cool post, looking forward to analysis of data retrieved. Thx.

Michael

I think many people don’t watch the weather and have no idea what is coming from week to week.
I’m a pretty good news hound but from the news programs you watch on TV you wouldn’t have any idea a cold front is on its way down. A big change is on the way.
I’m guilty of not knowing what the weather was going to be for the past 6 weeks or so. I was interested in different things
The news I got about this big cold front was right here on WUWT. Tonight I turned on the Weather Channel to see what is was all about.
All I’m saying is, a lot of people for whatever reason have no idea it’s going to be getting a lot colder.

Michael

[probably the worst, most off topic comment ever, TSA and Janet Napalitano have nothing to do with this story…..SNNNNNIP!]

Michael

This whole body scanner thing is like a science experiment. You should look at it from it’s inception to what we have today. It’s quite fascinating. I’m sure the psychology community will make a must review case study of it in the future.

Finally, something worth spending the taxpayers money on.

Ian H

@Steve Schaper: Very good analysis. Sounds right to me.
@jack morrow: Suggest you check your medication.

Hugh

Even now there are teams of environmental lawyers and scientists trying to figure out how to bring Hartley 2 within a global emissions trading scheme …

david

Beautiful … utterly amazing.
Even better, just 1 of these is all that’s needed to rubbish all 100 year climate forecasts … if it were closer we’d have something to really worry about, instead of computer models.

Arizona CJ

Beautiful, and a great post, thank you!
I’ve always been curious just how much the random jetting can impact a comet’s delta-v. From what I understand, it’s enough to alter their course slightly in some case, enough to make one predicted be be an earth-grazer on the outbound leg from the sun problematic to predict precisely. (There was a very entertaining Sci-Fi book called Lucifer’s Hammer based roughly on that theory).
However, given the main topic of this blog, I shocked that none of you see the real danger here; clearly, this comet is melting. Therefor, it can only be due to global warming…

Arizona CJ says:
November 19, 2010 at 12:27 am

I shocked that none of you see the real danger here; clearly, this comet is melting. Therefor, it can only be due to global warming…

And it is obviously due to all that CO2 being released – my model told me so when I programmed it to say that.

Aunty Freeze

‘NASA has just issued a travel advisory for spacecraft: Watch out for Comet Hartley 2, it is experiencing a significant winter snowstorm.’
Is Al Gore riding on the comet?

Malaga View

When heat from the sun reaches a pocket of dry ice—poof!—it instantly transforms from solid to vapor, forming a jet wherever local topography happens to collimate the outrushing gas. Apparently, these CO2 jets are carrying chunks of snowy water ice along for the ride.

Give me a minute… let me get my ducks in a row on this one.
1) Heat from the sun is warming the surface of the comet.
2) The comet has an atmosphere full of two greenhouse gases: CO2 and H2O.
3) The comet’s atmosphere is so cold that H2O is in the form of snow and ice.
Conclusion:
NASA Climatologists need to talk with professor Mike A’Hearn – left hand meets right hand – and agree a common line regarding Greenhouse Gases.
jack morrow says:
November 18, 2010 at 9:27 pm
professed what I saw or observed was a fact or made up some fiction as to what I observed. I am completely saturated with this crap…. There is more to it than a dirty snowball.

I am with Jack Morrow on this one… they make up so many stories… you never know whether to believe them… it’s the Cry Wolf syndrome… but I will go with there is more to it than a dirty snowball.

the2ofusr1

Comment: The Deep Impact mission to comet Tempel 1 was perhaps the most successful space mission for confirming Electric Universe predictions and confounding the consensus view of comets as inert, primordial icy bodies. If the scientific method were truly applied, the puzzles from Deep Impact 1 should have been cause for a review, not just of the current paradigm but also of every choice that led up to it.
Of all the forces we know, there is none stronger than a paradigm.
– Robert Stirniman.
I am grateful for WUWT and the many contributors as there is always 2 or more ways of observing things and This site being a weather watch dog with lots info has me stooping by and growing .I thought I would post this link above as they also provide a different opinion that allows me to escape from the power of the old paradigm ….peace

> There is more to it than a dirty snowball.
The dirty snowball concept was derived from Earth-based observations and was never meant to be the bottom line, hence the interest in sending actual probes to comets. I think the biggest problem with this article come from the author, it seems influenced from reading tabloids in the grocery store check out lane. Instead of filtering inane statements from scientists giddy from some great data and lack of sleep, they form the core of the press release. Combined with uncredited statements like “When heat from the sun reaches a pocket of dry ice – poof! – it instantly transforms from solid to vapor” it’s time to abandon the text and concentrate on the photos.
The similar story at http://www.jpl.nasa.gov/news/news.cfm?release=2010-387 is much better and could readily replace this post.
I’d post it here, but the link has extra photos of the comet, so if you’ve made past some of the inane comments to this post, check out the NASA page.

beng

As an astronomy buff, that’s an astonishing photo — it goes into my archive.
We need to find a way to grab some pristine comet fragments & return them to earth for study.

Malaga View

the2ofusr1 says:
November 19, 2010 at 4:16 am

I had to search for the link: http://www.thunderbolts.info/thunderblogs/thornhill.htm
It is an interesting read… whoch includes the following gem:
A history of unexpected discoveries is the hallmark of a failed hypothesis.

PaulH

Surely ice this old must be rotten ice. 😉

SteveE

Malaga View says:
November 19, 2010 at 2:14 am
When heat from the sun reaches a pocket of dry ice—poof!—it instantly transforms from solid to vapor, forming a jet wherever local topography happens to collimate the outrushing gas. Apparently, these CO2 jets are carrying chunks of snowy water ice along for the ride.
Give me a minute… let me get my ducks in a row on this one.
1) Heat from the sun is warming the surface of the comet.
2) The comet has an atmosphere full of two greenhouse gases: CO2 and H2O.
3) The comet’s atmosphere is so cold that H2O is in the form of snow and ice.
Conclusion:
NASA Climatologists need to talk with professor Mike A’Hearn – left hand meets right hand – and agree a common line regarding Greenhouse Gases.
—————————–
The comet is composed on H2O and CO2, it doesn’t have an atmosphere of those compounds. It’s much like the moon, where the temperature can range from -153 to +107 degrees C depending on whether you’re on the sunny side or not.
It sounds like your ducks are in the same shape as the Monty Python Parrot on that one I’m afraid!

wsbriggs

The Lucifer’s Hammer comment touched on what I was thinking.
What happens when a “dirty” comet strikes Earth. Suppose there are really BIG comets out there, that only come around every 10K or so years. If the Warmistas want to worry about climate change, they can have it all, GHG, eruptions, radiation (x-rays and better from ionized molecules during atmospheric transit.
I’d want a distant seat – say Mars – and some popcorn.

In the weird conception of the “Flintstones’ Pebbles Universe” theorists, comets are made of ICE-CREAM. Plasma and electricity does not plays any role in the universe, and they are all the time running after phantoms created by their own imagination,
As we are living in “interesting times”, where ALL nanny paradigms, concocted by a fantastic “post normal science” will inevitably die, the same as the French Revolution’s circle of 400 degrees or the square angle of 100 degrees, all these devised and invented with the sole purpose of making the peoples of the world ignorant of the laws transmitted from old, by all sages from the past, as Pythagoras and others, in order to build a complete secular society, where there would not exist anymore any references that anyone could relate with the laws really governing the cosmos, where there were no “laws” whatsoever, no “canon”, nothing but “chaos”.
http://www.scribd.com/doc/43332150/Unified-Field-Explained-9

Pamela Gray

Let me get MY ducks in a row. We are constantly searching for water and carbon in our universe. So here we have a comet filled with the stuff. So where did the water and carbon based lifeforms that resulted in an abundance of CO2 in this comet come from? Is it debris from our own planet collisions ejected out to an orbit? Or is it debris from another planet? If it’s from another planet is it one of ours from our Solar system, or one of “theirs”?

The EU model predicts that all active comets will exhibit frequent, short outbursts in different spots on their surface. The outbursts happen because they are electrical discharge phenomena, known technically as (cold) cathode jets. Their onset will be as sudden as an electric spark (described in one report as “nearly instantaneous”) and their duration extended only because space plasma has a limited current carrying capacity. The jets will focus on an extremely small bright area generally situated on a raised point or edge of the comet surface. In July 2004, I wrote in relation to Comet Wild 2: “In the electric theory, unresolved bright spots are to be expected where the cathode arcs impinge on the nucleus and give rise to the cathode jets. What do we find? “The most significant albedo, or at least brightness, features are rare small bright spots that occur in multiple images at different phase angles …ruling out the possibility that it is a phase effect or image artifact. In stereo images, it [a <50-m bright spot at the edge of a flat-floored depression] has no height. There is an adjacent shadow-like dark spot that could be the shadow of an optically thick jet… The bright spots are small and rare, suggesting that they may be short-lived.” Some of the jet sources are reported as tending “to coincide with the locations that are brighter than average.” The jets will form on the comet nucleus closest to its plasma sheath and where the electric field is strongest. Since the plasma sheath is generally closest in the solar direction, it has given rise to the notion that solar heating is responsible for comet jets. However, the solar wind strongly influences the comet’s plasma sheath, which may give rise to jets occurring on unlit areas of the comet.
http://www.holoscience.com/news.php?article=nq9zna2m
No need to say we need an “Astrophysical Gate” now…… Buy more popcorn!

SteveE

Pamela Gray says:
November 19, 2010 at 6:57 am
Let me get MY ducks in a row. We are constantly searching for water and carbon in our universe. So here we have a comet filled with the stuff. So where did the water and carbon based lifeforms that resulted in an abundance of CO2 in this comet come from? Is it debris from our own planet collisions ejected out to an orbit? Or is it debris from another planet? If it’s from another planet is it one of ours from our Solar system, or one of “theirs”?
———————
Not sure your ducks are looking that healthy either…
Why do you need life forms to have made the CO2 in this comet? Venus’ atmosphere is 96.5% CO2 and I’m pretty sure it wasn’t made by any life forms. The same is true of Mars. Volcanoes spew out about 300 million tons of CO2 a year (about a hundred times less than humans emit though) and none of that is from life forms.

joe

2km from end to end and how long would it take to evaporate giving off basketball sized chunks?
quite unlike the phenomenon of snow, isnt it?

Malaga View

SteveE says:
November 19, 2010 at 6:08 am
It sounds like your ducks are in the same shape as the Monty Python Parrot on that one I’m afraid!

Precisely my point… I don’t think many people do have their
ducks in a row… but the plasma guys seem to be getting their cathode jets in a row.

Pamela Gray says:
November 19, 2010 at 6:57 am
We are constantly searching for water and carbon in our universe.

They didn’t bat an eyelid on that one… so best not to play poker with them… or is it just a case of Light On – Nobody Home… my guess is that they are just trying to bluff it out knowing full well that they hold a busted flush.

Manitoba Ken

Is that cool or what? At least some departments at NASA are still in the game.

James F. Evans

The electromagnetic analysis & interpretation of comets is more persuasive than the so-called “dirty snowball” analysis & interpretation, in my opinion.
The Electric Comet
http://thunderbolts.info/pdf/ElectricComet.pdf

Malaga View says:
November 19, 2010 at 8:23 am
Guess those ducks are PINK DUCKS and very sophisticated. 🙂

captainfish

I have a stupid question. If so many comets are releasing CO2, and those comets continue to fly in our general direction,….
Would our gravity attract those CO2 molecules and increase our CO2 PPM density?

Breckite

I want to ski the comet.

captainfish says:
November 19, 2010 at 12:03 pm
That question will be gladly answered by Al “Baby”

Last week I went to a lecture by the PI for the Magnetometer on the Cassini-Huygens probe. Fascinating views of Enceladus, which has ice particle geysers at its south pole.
http://en.wikipedia.org/wiki/Enceladus_%28moon%29

tallbloke says:
November 19, 2010 at 12:11 pm
Interesting its “Tidal heating” (gravity turned back to IR radiation). But that’s contrary to the view of airtight compartments between different forms of energy(wrongly called “mass”) held by post normal science, where only LWR from the Sun warms up planets…
That would enrage some known friars of the “holy astrophysical inquisition”. 🙂

….perhaps they will explain it by their current model, which by “reductio ab absurdum”, use imaginary numbers, obtained by reducing the two fundamental forces to just one vector: sq.root of -1.

Though, in the Enceladus case, it could be also caused by anathematized electricity.

Bruce Cobb

Could “snowstorm on a comet” be another phrase like “tempest in a teapot”?
An analogy for something interesting, but of not much consequence, perhaps.
Not unlike Cancun.

sky

In a world full of scientific chicanery, are we absolutely sure that’s an image of Hartley 2? It looks more like my dog’s tongue after slurping dropped hamburger off the patio!

WestHoustonGeo

Quoting jack:
November 18, 2010 at 9:27 pm
OK. So far it seems everything takes “scientists” by surprise…What a bunch of crap! …There is more to it than a dirty snowball.
Commenting:
Speaking as a Scientist, “Lighten up, fly-boy!” D0 pilots have all the answers on incomplete data? Scientists observe and try to explain what they see. The better they see, the better they explain. Sometimes they don’t get it right and that makes hot dog pilots laugh. Most times they get it right and you airheads ignore it!

Breckite says:
November 19, 2010 at 12:10 pm
> I want to ski the comet.
Prepare to be rather disappointed. You’ll want to ski at a speed less than escape velocity. The orbital velocity for an object as dense as Earth is about 90 minutes, size cancels out in the math. Comets are much less dense, and the post’s “The icy chunks are moving away from the comet’s surface at only a few m/s (5 to 10 mph)” must be well above escape velocity.
Even a “real” moon like Deimos has challenges to turn it into an exciting sporting event. I made a stab at writing an April Fool’s Day story about it, but I couldn’t find Deimos’ density and used Earth’s. Even with that I figured I’d leave the time aspect out of my description. Turned out pretty well, though. See http://wermenh.com/deimos.html . I updated the photo of Deimos a few years ago.
Now, a jet pack and a mesh bag, and a goal of collecting the biggest volume of snowballs without them breaking up and pieces drifting through the mesh, that might be a bit of fun.

Gavin

From Science@ NASA article:
“Data collected by Deep Impact’s onboard infrared spectrometer show without a doubt that the particles are made of frozen H2O, i.e., ice. Chunks consist of micron-sized ice grains loosely stuck together in clumps a few centimeters to a few tens of centimeters wide.”
Regarding the “frozen H2O”, for anyone that may not have read it the link posted by Malaga View it says:
“Most of the volatiles detected in cometary coma are formed not by solar heating but by electrical ‘cathode sputtering’ of the high-temperature minerals on the comet surface. The evidence for this comes from the ‘puzzling’ abundance (densities at least 100 times greater than expected) of negative ions near the nucleus. The negative ions combine with the positive hydrogen ions from the solar wind to give, amongst other things, the OH radical, which is then misinterpreted as signaling the presence of water ice on the comet. That is why all other means of detecting significant water ice on comets have generally failed.”
http://www.thunderbolts.info/thunderblogs/thornhill.htm
There is also this link on Hartley 2
http://www.thunderbolts.info/tpod/2010/arch10/101105hartley.htm

kuhnkat

Someone want to explain the difference between confirmation bias and what we have here?? I don’t see ice and snow. Why do they???

kuhnkat

One question.
Isn’t this comet too far from the sun, according to their models of comet behavior, to have this type of jet action????

Ian H

A skeptic is someone who requires strong proof before they will accept strong claims. Judging by some of the comments in this thread there are a lot of non-skeptics here who apparently believe the most bizarre rubbish on the basis of no evidence whatsoever.
Electric universe cultists. Please go away. Your theory is a bunch of incoherent drivel. What – you think a website full of diehard skeptics is going to give your pseudoscientific claptrap an uncritical reception? Go found your own website and leave us alone or we will mock you mercilessly at every opportunity.

Gavin

>Electric universe cultists. Please go away.
Your knee jerk reaction sounds like some of the more extreme AGW people who refuse to consider another point of view.

“Comets also have ‘magnetospheres.’ The cometosheat consists of decelerated plasma. Confirmation that pinched Birkeland currents also occur in cometary magnetospheres was obtained by the detection of X rays from Comet Hyakutake in 1996.” http://public.lanl.gov/alp/plasma/downloads/AdvancesI.pdf

Gavin says:
November 20, 2010 at 3:08 am
Electric universe cultists. Please go away.

That´s chemically pure fanaticism. It´s over buddy!. As the great George Carlin said:
Pack you sh**s folks, WE are leaving”!!

Gavin

@Enneagram
I think you’re pointing your finger at the wrong person. I was quoting Ian H’s comment at 11:58pm.
I am open to the idea of an electric universe because the guys who research it can explain a lot of stuff that mainstream science can’t.