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.
“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.
“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.
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
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.
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.
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.
Oh and cool post, looking forward to analysis of data retrieved. Thx.
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.
[probably the worst, most off topic comment ever, TSA and Janet Napalitano have nothing to do with this story…..SNNNNNIP!]
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.
@Steve Schaper: Very good analysis. Sounds right to me.
@Jack morrow: Suggest you check your medication.
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 …
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.
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
And it is obviously due to all that CO2 being released – my model told me so when I programmed it to say that.
‘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?
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.
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.
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.
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.
Surely ice this old must be rotten ice. 😉
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!
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
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!