Note: See updates below for the ISON ISOFF ISON nature of this comet that has everybody guessing. Picture at right also updated to reflect the new “zombie” status of this comet.
Looks like ISON has disintegrated during its turn around the sun. Given the radiation (estimated temperature 5,000F/2,760C – hot enough to vaporize rock), solar wind, and the tidal-forces (even though smallish, thanks Gavin) associated with its proximity and nearly 800,000 mph speed around the turn about that time, I’m not surprised. Watch the second video below where it goes “poof” (h/t to reader “David”)
NASA’s spaceweather.com reports:
Comet ISON is making its closest approach to the sun, and evidence is mounting that the nucleus of the comet has disintegrated. Watch the head of the comet fade dramatically as it approaches the sun in this SOHO coronagraph movie:
(may take a minute to load)
![sundiver_anim3[1]](http://wattsupwiththat.files.wordpress.com/2013/11/sundiver_anim31.gif)
The movie spans a day and a half period from Nov. 27th (01:41 UT) to 28th (15:22 UT). In the early hours of the 27th, Comet ISON brightens dramatically, saturating the pixels in the digital camera of the SOHO’s coronagraph. By mid-day on the 28th, however, the comet’s head appears to fade. This is a sign that the nucleus has likely fallen apart. That would make ISON a headless comet–more appropriate for Halloween than Thanksgiving.
Researchers working with the Solar Dynamics Observatory report that they are seeing nothing along the track that ISON was expected to follow through the sun’s atmosphere.
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UPDATE: Watch it go “poof” here:
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UPDATE2: NASA JPL Insider Amy Mainzer tweets some last minute hope that ISON may be “undead”
http://twitter.com/AmyMainzer/status/406179229487742976
A zombie comet, how cool is that?
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UPDATE3: Now it seems back again, but looking entirely different than before. A number of astronomers indicate they don’t know what is left of it, maybe a chunk, maybe a smooshed drawn out nucleus or something else. Image from SOHO’s coronagraph:
Dang it, I’ve been over on the previous thread http://wattsupwiththat.com/2013/11/27/watch-live-updates-on-comet-ison/#comment-1487038 talking to myself not realizing there was this thread! Over there you’ll see comments wherein I claimed ISON wasn’t dead at November 28 2151UT. And that it is continuing to brighten again.
Rich.
I looked at you posts owe to Rich.
1minute b4 you posted
” but from my view of LASCO C2 20:36UT (74 minutes ago) a small remnant has survived.”
I posted…
“It’s now looks like ISON survived the arc discharge without serious damage.”
So i beat ya
:p
meemoe_uk said:
I believe that Nobel/noble prizes can be shared by a small group, so in light of my earlier comments on the other thread I offer myself up as a co-conspirator! /sarc
It looks as if the coma of ISON was completely blown away leaving only the nucleus which was too small to be seen, hence the reports of “demise”. Probably many comets have done this in the past but it is only now that we have the technology to even try and see what is going on – and then failed effectively! In the old days people saw a comet approach the Sun, lost sight of it, and saw it come back out again; they didn’t know what happened to it at perihelion.
Regarding the tidal phenomenon, one can think of it as the near side of the comet is trying to follow a slightly different orbit from the far side (going to ignore rotation here), so it does require some cohesive force to hold it together. I don’t know why no-one has done the maths to work out whether a 2km body’s own gravity is enough to counter the tidal force at ISON’s perihelion position. Leif?
A further question would be whether, if part of it was pulled slightly apart, as it moves further away from the Sun and the inverse cube effect decreases more rapidly than its own internal inverse square effect, could it come back together again? Someone, somewhere, may already have calculated this sort of thing.
And then there are the variable internal structural forces to consider, if as people say it is more rock than ice.
Anyway, it’s a privilege to be witnessing this,
Rich.
meemoe_uk (“So i beat ya”) – we just cross-posted. I might just give you the biscuit. It’s true that when I said “small remnant” I did think that the nucleus might have been seriously reduced in size. I don’t think we’ll ever really know, because even now good estimates of nucleus size seem difficult because they are so small compared to the obscuring coma.
Anyway, well done mate! (I may withdraw that if I can’t see it even with binoculars.)
Rich.
@Scuzza Man
Great comment, I totally agree. The MSM is dominated by empty-headed “drive-by” journalism and sensationalism. We don’t want that to happen here on this blog, which should always strive to be scientifically accurate and unbiased.
😐
Well then, I guess if ISON could speak, it would say “the report of my death was an exaggeration”.
As of 14.24 French time, NASA is still claiming “Comet ISON Fizzles as it Rounds the Sun”:
http://www.nasa.gov/content/goddard/comet-ison-fizzles-as-it-rounds-the-sun/#.UpiRr9JDu1g
Presumably, they’re still looking for the right words to cope with the incomprehensible (because uncomprehended) update.
When is going to be the best view we will get from earth of ISON, or is it too late?
Ison 1 – Sun 0
Ison is brightening fast as it leaves the suns corona, similar to other sun grazers that loose their tail and surrounding gas cloud as they get too close to the sun.
http://soho.esac.esa.int/data/realtime/c3/512/
This seems like a good time and thread to mention the late, great astronomer Dr. Thomas C. Van Flandern’s web site http://www.metaresearch.org. He asserted comets and asteroids were essentially the same thing – the remnants of one or more exploded planets. (It seems Mars was the moon of one of these doomed giant planets.) I don’t recall ever seeing metaresearch.org mentioned on this site. I love it for his well thought out, out of the mainstream thinking.
A better fit, perhaps the Lazarus-comet? (looks to predate the term ‘zombie’ by centuries; Zombiw was first used, it appears, by Canadian anthropologist and ethnobotanist Wade Davis in Haiti in 1982 or so to describe a particular human ‘state’ he had observed)
.
If only were IPCC…
It seems unlikely that “zombie” was first used in 1982 given that there was a pop band called “The Zombies” in the mid-sixties. I remember the classic song “She’s Not There”.
Perhaps ISON should be called the just-like-climate-change-it’s-totally-normal comet 🙂 That’s another one for #ClimateThanks !
Richard.
meemoe_uk says:
November 29, 2013 at 2:04 am
“Rocks”? “They”? What broke up SL-9 near Jupiter? Not much solar heating there, you can do the math, ISON got to some 0.013 AU of the Sun before breaking up.
From http://en.wikipedia.org/wiki/Deep_Impact_%28spacecraft%29 :
See – owe to Rich says:
November 29, 2013 at 5:02 am
I don’t know why no-one has done the maths to work out whether a 2km body’s own gravity is enough to counter the tidal force at ISON’s perihelion position. Leif?
One way of getting a feel for this is to calculate the gravitational accelerations. For the Sun at ISON’s closest approach gSun = 33.4 m/s/s i.e. only about three times that we enjoy on the surface of the Earth. The difference in gSun that the 2 km diameter of ISON makes is 0.00007 m/s/s. ISON’s own g force is [based on a mass of 3E12 kg] is 0.00020 m/s/s or three times larger than the tidal force. If ISON has ANY cohesion at all [like rock or even a snowball] that just adds to the difficulty of tidal breakup.
See – owe to Rich says:
November 29, 2013 at 5:02 am
I don’t know why no-one has done the maths to work out whether a 2km body’s own gravity is enough to counter the tidal force at ISON’s perihelion position. Leif?
The distance within which tidal breakup occurs is called the Roche-limit. Wikipedia has a good article on that http://en.wikipedia.org/wiki/Roche_limit but the table for selected examples is wrong [the unit should be km not meter]. Anyway, you can see that ISON is outside the Roche limit.
pop-culture references or first use by a ‘scientist’?
‘Zombie-ism’, per se, has been known as part of voodoo (more correctly: Vodou).
Haitian Creole: zonbi – http://en.wikipedia.org/wiki/Zombie
“Zombi” is also another name of the Vodou snake lwa Damballah Wedo, of Niger–Congo origin; it is akin to the Kikongo word nzambi, which means “god”. There also exists within the West African Vodun tradition the zombi astral, which is a part of the human soul that is captured by a bokor and used to enhance the bokor’s power.
.
Could add: “The most well-known researcher to explore the Haitian zonbi is Wade Davis, an ethnobotanist:” per http://www.umich.edu/~uncanny/zombies.html
French_Atkins says:
November 29, 2013 at 3:29 am
As a fellow “astronomo-sceptic”, I totally agree with what meemoe_uk has been saying about an electric interpretation of what is unfolding before us.
Man, your ignorance runs deep.
@_Jim
> Zombiw was first used, it appears, by Canadian anthropologist
> and ethnobotanist Wade Davis in Haiti in 1982
The Wikipedia article you are quoting doesn’t say that Davis was the first to use the word. Need to consult an etymology dictionary, which shows word origins:
http://www.etymonline.com/index.php?allowed_in_frame=0&search=zombie
zombie (n.)
1871, of West African origin (cf. Kikongo zumbi “fetish;” Kimbundu nzambi “god”), originally the name of a snake god, later with meaning “reanimated corpse” in voodoo cult. But perhaps also from Louisiana creole word meaning “phantom, ghost,” from Spanish sombra “shade, ghost.” Sense “slow-witted person” is recorded from 1936.
What broke up SL-9 near Jupiter?
It got zapped electrically. Same way all comets go.
ISON got to some 0.013 AU of the Sun before breaking up
Ison didn’t break up
New news :
Ok everyone, it’s now past 50% odds that Ison’s old trailing tail is going to fade away to obscurity, while the secondary angled at 90deg to its old tail is turning into its main tail.
What u think to that Leif?
As ‘glow’ generally involves ‘plasma’ processes (excited gases) and therefore requires gases at a certain pressure (probably non-existent in the vicinity of the comet) between which electrons travel, how would this modify the “GLOW-mode” discharge process (is this a discharge as in a Neon or Argon lamp)? A further question, what is the method of continuing ‘charge separation’ (or charge accumulation) such that the glow or discharge process may be continued (made continuous, to support continued or continuous glow, etc) by the comet-mass in order to achieve these phenoms?
.
Some people’s pop cultural coolness needs to be improved. “Zombie” is definitely older than 1982. The modern shambling version goes/shambles back to “Night of the Living Dead” (1968); the classic Hollywood variety to Jacques Tourneur’s “I Walked with a Zombie” (1943).The Hollywood ur-example being “White Zombie” (1932; eminently shuddersome, but not for the Un-Grateful Dead). The concept was popularized by William Seabrook in “The Magic Island” (1929), which defined all the trashy voodoo/hoodoo concepts about Haiti while ignoring the sordid truth.
re: John Day says November 29, 2013 at 7:24 am
Already covered that aspect, but thanks anyway. (Day late and a dollar short.)
re: Ulrich Elkmann says November 29, 2013 at 7:32 am Some people’s pop cultural coolness needs to be improved. “Zombie” is definitely older than 1982.
See addenda above, and please, try to keep up …