ISON Experiments – CIOC

At the Comet ISON Observing Campaign (CIOC) meeting in August 2013, some outstanding scientists led by Dr Mike Mumma of NASA Goddard Centre for Astrobiology, discuss their experiments for Nov/Dec 2013

Mumma mentioned that their studies have a population of 26 Comets. They have already identified 24 molecules. They are interested in comparing Kuiper Belt Comets (which move elliptically in the plane of the ecliptic) to Oort Cloud Comets (ISON).

The experiments will have the following overall objectives. 

The main points I took home : 

  • The level of sophistication of our scientists’ study is well beyond most peoples vision or comprehension
  • Water is already accepted as the pre-dominant “non organic volatile” 
  • Extensive experiments on 14 previous COMETS will be continued on ISON 
  • A “taxonomy” (ie classification system) is evolving for Comets. But I notice exoComets are not yet part of the planned taxonomy
  • ExoComets get a promising mention on one slide : The origins of Oort Cloud Comets is still uncertain – are they exoComets. I say “YES”. 
  • Finding “life” continues to be a challenge until NASA defines what are the biomarkers for life – expect paper in 2014 by NASA astrobiologist Chris McKay. Focus will continue to be looking for complex molecules required in DNA. 

ISON presents yet another opportunity to continue the relentless advance of human discoveries.

This one slide, showing the “paradigm changing items”, is probably enough detail for this BLOG. See the video to understand where we are in the actual realization that “Life IS a Cosmic Phenomenon”. 

They seem to have not considered the possibility that inbound hyperbolic comets like ISON might come from adjacent stars. It is only after the kind of event we saw yesterday (where ISON’s eccentricity dropped below “1.00”) that the SUN captures the COMET and traps it in an elliptical orbit of thousands of years. ISON’s orbit period is now 400,864 years 🙂 Sorry ISON. I will sadly not be around when you finally return 400,000 years from now.

To understand the “capture” (or non Capture) issue better, click here to see an explanation from JPL’s Dr Alan Chamberlin on why, even though “e” has just dipped below “1”, it is not correct to say that we’re witnessing the capture of comet ISON.

ISON Captured by SUN? Not necessarily

Sunday Nov. 24, 2013 : (Question to JPL) Dear Alan (Chamberlin) at JPL :  Is this statement accurate?  If not how would you reword it?

Big day for ISON yesterday. I noticed today the eccentricity dropped below “1.00”. Does this mean NASA is now calculating it is no longer on a hyperbolic orbit heading out of the solar system, but is now on an elliptical path? Today e is now .9999977109551715 with newly calculated orbit time of 400,864 years – ie Big News – Has ISON has been captured by the SUN and is now in a very long elliptical orbit. I suspect this is a historic moment when we have just seen an exo-COMET captured by our sun.

Monday Nov 25, 2013 : (Response from JPL) Hi Bill, The current orbit (51) for Comet ISON is represented as heliocentric osculating orbital elements at epoch 2013-Nov-04.  The eccentricity listed on our web-site (0.9999977109551715) has a formal uncertainty of 9.8317e-08 (i.e., on the order of 1e-7 1-sigma).  Note that this puts the eccentricity not very far away from 1.0. 

One important issue is that these elements are with respect to the Sun — not with respect to the solar system barycenter.  It is quite common to see comets with e slightly less than 1.0 with respect to the sun and e >= 1.0 with respect to the solar system barycenter.  The other important issue is to understand that these are osculating elements which effectively means they change with respect to the epoch used (i.e., they are representative of a conic orbit which just touches the actual orbit at that epoch and are handy for quick-and-dirty 2-body propagation).

If we look at the heliocentric osculating elements (specifically e) at other epochs, we see that e is greater than 1.0 except for epochs close to perihelion (i.e., the point at which the comet is closest to the sun), 2013-Nov-28.  See output below from Horizons. 

It’s important to be careful about saying too much based on osculating elements and it’s just as important to understand what they are.  I can only recommend you find some reference materials on the subject if you’re interested as I’m unable to give you a substantial primer.  It’s also important to take into account uncertainties in any object’s orbit.  

In any case, it’s not correct to say that we’re witnessing the capture of comet ISON. 

I hope this helps. With kind regards, 

Alan 

———————————————————————–

Dr. Alan B. Chamberlin, Jet Propulsion Laboratory, Pasadena, CA 

 __________________________________________________________________________

Post Script

I believe Dr Chamberlain is helping us understand that JPL has currently “51” different sets of orbit parameters for ISON, taken over time . Each set are different – ie the orbit  subtly changes as the comet comes into the inner solar system and gets affected by the inner planets (esp Jupiter).  He points out “we see that “e” is greater than 1.0 except for epochs close to perihelion”. He even notes that although “e” is “< 1 in epoch 51, the “uncertainty parameter ” associated with “e” is sufficiently high to “put the eccentricity not very far away from 1.0″. In effect he is warning me that the orbit is still pretty much parabolic and we cannot draw the conclusion it has changed from “hyperbolic” to ” elliptical” (or that ISON has been captured). Within days, if it fragments and there are large clumps left, these may well become “elliptical” and be CAPTURED by the SUN.  BUT ISON has not been captured by the SUN YET.  i.e. it’s trajectory is still the same : it is heading around the sun and off through the Oort Cloud to another star.              

 

ISON – In Memoriam

In Memoriam

 
 
“Born in a dusty and turbulent environment, comet ISON spent its early years being jostled and struck by siblings both large and small. Surviving a particularly violent first few million years, ISON retreated to the Oort Cloud, where it maintained a largely reclusive existence for nearly four billion years. But around 3-million B.C., a chance encounter with a passing star coerced ISON into undertaking a pioneering career as a Sungrazer. On September 21, 2012, ISON made itself known to us, and allowed us to catalog the most extraordinary part of its spectacular vocational calling”.  Karl Battams, CIOC (NASA’s Comet ISON Observing Campaign.
 
  

Log of Comet ISON Sightings

Cattle Point Urban Star Park, Oak Bay, Victoria, BC, Canada

Sunday Nov. 24, 2013  Big day for ISON yesterday. I noticed today the eccentricity dropped below 1. Does this mean NASA is now calculating it is no longer on a hyperbolic orbit heading out of the solar system, but is now on an elliptical path? See NASA JPL database. Today e is now .9999977109551715 with newly calculated orbit time of 400,864 years – ie Big News – ISON has been captured by the SUN and is now in a very long elliptical orbit. I suspect this is a historic moment when we have just seen an exo-COMET captured by our sun.

For next week as ISON passes the closest to sun on Thursday, we will not be able to see ISON from earth. BUT GOOD NEWS, as well as Hubble (in space) and ALMA (on earth) we have the amazing STEREO with its two space-based observatories – one ahead of Earth in its orbit, the other trailing behind. This is how we will “see” ISON during this key 7-4 days. If ISON does break up, during this time, STEREO should be able to show us how it looks during and after the disintegration. This is worth looking at – CIOC (NASA’s Comet Ison Observing Campaign).  

The CIOC Team

Metchosin, Victoria, BC, Canada

Saturday Nov. 23, 2013 :  This morning sighting of ISON in BC, Canada was a tough one. All I used was my 15X70 binoculars. It was well below the level of Mercury and even Saturn had risen above the level of the cloud band hugging the ocean before I could see it. It was past 0630. The core was clear but the coma was very faint and no tail was visible. By 0645 the comet was no longer visible but I was able to be sure of the correct area because there were still a couple of stars visible in the field. Then to the far west of the binoculars FOV a bright, slow moving satellite drifted into the field. I tracked it until it faded out. While I was doing this I thought that it was so bright it must be the International Space Station. Checking the NASA site when I got home confirmed it probably was. Cool, the ISS passed right through the same FOV as the comet even though I couldn’t see it.  Well, that’s it for sure until sometime in early December…..Maybe? 

Friday Nov. 22, 2013 : Although I will give it one last shot tomorrow this morning was probably the last chance for our latitude to be able to observe the so called “Comet of the Century”. I was back at Taylor beach again 15X70 binoculars and 6 inch dobsonian in tow. There was some haze but by about 0615 hrs Mercury had risen enough above the thick haze to think about having a go at it. The comet was just visible with the binoculars due to the brightening sky and haze. Still, thinking about the conditions I feel it is brighter than the day before so I switch to the scope. It didn’t take long to sweep it up and very low power. I switch to an eyepiece that gave60X magnification and a 1.66º FOV. Although no tail was visible a nice bright core and fainter outer halo showed. At that point the couple that I have seen daily walking the beach came by so I showed them the comet. Then before I packed up we all had to leave for work, I gave them a quick show of the Moon and Jupiter. 

So will this be the last we see of this comet or will it survive the Sun? As it will now be dipped below the horizon I guess in a week or so we will know the answer. As I was about to depart the beach I balance my old cheapo point and shoot digital camera on the tsunami zone sine and snapped this parting shot at around 0635 hrs.    http://rascvic.zenfolio.com/p566114947/h12711407#h12711407 I’ve marked Spica, Mercury and the comet. Blown up it actually shows a dot in the circle. 

I will be back at the beach for one more try Saturday morning but I’m not holding my breath on seeing it. Then again, you won’t know unless you give it a go. Bill Weir, in Metchosin, Victoria. BC, Canada

Friday Nov 22 Cattle Point Urban Star Park, Victoria, BC : 

Bill Smith :  HERE IS COMET ISON. With my naked eye. Yesterday with cloud on horizon over Seattle, two clear white streaks could be seen but I thought it just could not be ISON with my naked eye and such cloud. Well right now FRIDAY morning with a beautiful sunrise (with sun still below horizon) at 07:13 am, there is COMET ISON across the Salish Sea towards Seattle as seen from Victoria. Exact same place as yesterday – memories of Hale-Bopp came back. The streaks are exactly where you would predict they would be – and yes – there are two enormous streaks way longer than I expected, due to sun shining on the two (at least two) long tails – the Devil’s Horns. Bill Smith in Oak Bay, BC



The comet is right in the centre. This was taken with a 2 year old LG Smartphone and so does not show ISON too well. But for me this is a very personal moment I want to document. I ask you to believe that with the human eye the two tails were clearly visible.

NASA Stereo : STEREO consists of two space-based observatories – one ahead of Earth in its orbit, the other trailing behind. With this new pair of viewpoints, scientists will be able to see the structure and evolution of solar storms as they blast from the Sun and move out through space. Stereo focuses on Comet ISON. 

Thursday Nov 21, Victoria, BC : 

Bill Smith : Excellent 1 hour show on PBS last night – “Comet (ISON) Encounter”. Try to see it. Early this morning from Cattle Point Urban Star Park looking ESE down to Seattle from Victoria. Clear skys except on horizon. Through clouds two clear white streaks could be seen but I think at least one of these was perhaps from the moon behind the sunrising sky. Not confident either was ISON. Bill Smith in Oak Bay, BC

Bill Weir : I arrived at Taylor Beach again around 0550. This time along with my 15X70 binoculars I also had my 6 inch dobsonian telescope. Unfortunately a thin cloud bank hung over the Strait in precisely the area of the sky I needed clear. I got a very short break as the cloud drifted and made another observation with the binoculars. The tail and coma of the comet looked exactly as they did the day before but the core was noticeably brighter. Then the clouds snapped shut and I was shut out from then on. I did set up the 6 inch but never got to observe the comet with it. I waited until 0645 then had to head to work.

Now here’s the rant. All the hype by the media (which is started by the scientific community) about the comet really bugs me. While I was sitting waiting for the clouds to drift two cars drove up. One had a 60+ish couple and the other contained a young dad with his three young children who were all for sure under 10. All were there to see the comet. They all seemed to be under the impression that all they had to do was get out of the car and there emblazoned across the sky would be the “Naked Eye, Comet of the Century”. I unfortunately was left with the task of breaking their bubble.  At least before they left I was able to give a condensed lesson on comets and the kids I was able to show a very sharp view of Jupiter with my 6 inch scope as the seeing was excellent. I also left them with the reassurance that if it was clear the next morning at that time they would be able to find me sitting in the open back of my Forester observing the comet. Bill Weir, in Metchosin, Victoria. BC, Canada

Wednesday Nov 20 Victoria, BC :  I got up earlier than normal so I could drive to Taylor beach and check out ISON. All I used was my 15X70 binos on a tripod. The comet (located to the southwest of halfway between Spica and Mercury) showed nicely with a strong nucleus, small but defined coma and a long thin tail. Very pretty. Knowing  exactly where to look I could just make it out naked eye against a rapidly brightening sky. Bill Weir, in Metchosin, Victoria. BC, Canada

Tuesday Nov 19 : ISON today. 2013 11 19 UT. naked eye: faint 4.2.. no visible. Dr. Salvador Aguirre

Tuesday Nov 19  Victoria, BC : This morning a new acronym came into my life, “A hag”. It stands for Always have asto gear. I’ll explain. At 0650 hrs while driving towards Victoria on highway 1  while at around Portage Inlet I was admiring the beautiful clear sky above a dark band of clouds when I noticed a little tiny white dot. I thought, Mercury how nice. Then it was MERCURY, that’s the area of the sky I need for ISON. It was actually not all that hard while driving in morning traffic to every once in a while locate Mercury and not be a traffic hazard.  I also took note regularly of features to the clouds below Mercury. Eventually I made it to Mayfair Mall and pulled into the upper parking lot. This is where being A hag guy comes in. In my car I have three pairs of binoculars (10X40, 10X50 and 15X70). I also have a PST (Solar scope) and camera tripod. I also like to leave the 15X70s at focus for the Moon so they are closer to focused on infinity for spotting stuff in a bright sky. With only a tiny bit of sweeping, because I had noted the cloud pattern I was able to pick up Mercury with the binoculars and then naked eye again. With Mercury in the south east, Mars close to the meridian and the Moon off in the west I had my ecliptic path. With this chart http://observing.skyhound.com/ISON.html  I knew comet ISON was just a few degrees to the SE of Spica. I also knew that Spica lies just south of the ecliptic.  With the 15X70 binoculars I started to slowly trace a line towards Mars and it wasn’t long before I picked up the tiny spark of light from the core of the comet. At first I thought it could be the 1st magnitude Spica but I continued on my westward scan and soon came to a much brighter white dot, Spica. I moved the binoculars back to the south east and settled again upon the tiny faint glimmer of the comet. No coma, no tail but still a sighting, and from the reasonably bright sky at 0705 hrs PST. I’m happy. If the sky is clear tomorrow morning I think I’ll be getting up a little earlier. This is why it never hurts to be “A hag”. Bill Weir

Charles Banville :  Location Unknown : I used a 135mm lens on my DSLR to locate the comet. Once I located it I switched to a 400mm lens. The moon was extremely bright and I did not see the comet with my unaided eyes. Charles Banville.

Friday Nov 15, 2013 : Yes, I saw it and Lovejoy last Friday morning, Nov. 15th, locating them easily with 12×63 binoculars, then with the naked-eye with difficulty.  Both were about 5th magnitude. Starry Skies, George W Gilba

Please provide your locations : wesmith@outlook.com

 http://waitingforison.wordpress.com/november-2013/ 

ISON ALIVE – the excitement continues

Saturday Nov 30, 2013

19:42 UTC : Bye Bye ISON? A “sublimated” Comet is now reduced to a cone of molecules (mostly H and O) being blasted as a cone away from the sun by the solar winds. I wonder if the Northern Lights will be affected over the next day or two (estimated time for molecules to arrive at earth)? 

00:19 UTC : ISON particles (after fragmentation) significant enough to track. Light reflects mostly from Oxygen. Usually tail points away from SUN towards future trajectory. Not in ISON’s case. Although not having a 3D image, it is hard to get a sense of the direction of the ISON sublimation blast cone. You can see here how the blast cone is unsymmetrical. To the left the particles are blasted out and away from the sun,but to the right the blast cone seems to be “pulled back towards the sun” by the turbulance.

Friday Nov 29, 2013 : Yesterday lunchtime at Cattle Point Urban Star Park, we bit our nails with excitement waiting for ISON to reappear from behind the sun (or SOHO’s sun cover). Google+/Youtube had carried the event live around the globe. It was an exciting build up.  I was even pleased with Phil Tait’s involvement as the BadAstronomer.

As the critical moment came, and as we waited and waited, ISON did not reappear. One of the panel stated he was sure ISON had disintegrated (or sublimed), and a look of disappointment came across all the faces of the show participants as each came to the conclusion he was likely right. One by one with their tails beneath their legs, all the Google+ participants left the show. By 1 pm the show was over and ISON was DEAD.

NASA, keen to get home to their turkey dinners, sadly and quickly announced that ISON had “sublimated” with all its molecules absorbed by the sun’s heat and gravity. I was thinking that maybe the solar wind would in fact blast the particles below a certain size out in a cone which might or might not reach the earth in 2 days time – and that might still happen on Saturday.

Well with Google/NASA on their way to dinner, the only people left was ESA (European Space Agency). About 13:30 a twitter from ESA announced  “Stay tuned, but it does seem that a remnant of ISON’s tail follows the comet’s trajectory. Images refresh here:

I couldn’t contain my excitement.

I twitter back to ESA :  the tail should point away from the SUN after the perihelion – so says all the blogs? True?

Their response was even more devasting : Our scientists have confirmed, comet is gone , thanks for sharing this comet-watching night with us

 I quickly updated my Facebook to delete my new ISON is ALIVE post. 

The evening and night passed slowly as I mulled over ISON’s demise. I was heartened by all the great science results people like Dr. Tony Remijan (ALMA) must have got and thought about Dr. Mike Mumma’s planned experiments which I expect will have produced many scientific advances ( see http://bcmeteors.net/index.php/77-news/170-ison-experiments-cioc ) BUT will ALMA finally prove that the seeds of life itself are carried by the (already proven) water of the core of ISON. Hopefully. 

Well suddenly at  09:45 Friday Nov 29, we get the great news in an @ScienceChannel twitter that ISON (at least the tails and fragmented core) may have survived its trip around the sun : 1h . Comet ISON may have survived its trip around the sun! Here’s the latest:

What a roller coaster you are ISON. And “what next?” we are all asking  🙂

Predictions (in fun) :

  • Great Northern Lights tomorrow + some satellite and radio issues starting tomorrow (as particles carried by solar wind reach earth)
  • Great views of comet ISON starting in 2-3 days as the remnants shoot off to the Oort Cloud and possibly to another star. Early morning (6:30 am) in ESE.
  • Exciting meteor showers mid-January (as earth passes close to the tail-end of the still surviving tail 

Apparently Oxygen is the key element which gives bright light from a comet. So the trailing tail could be oxygen or even actually water vapour. 

Question : Strange. The 2 tails are meant to point away from the sun after the perihelion. What are we seeing here? Could it be sunlight reflecting off the debris trail? Clearly a debris train containing much oxygen. So is it possible if ISON had not had this sublimation event that the tails would point in the opposite direction away from the Sun? But bright light means oxygen. So has disintegration caused trailing particles containing oxygen. My bet is this is mostly water (ie big particles), as if it was oxygen molecules the solar wind would have blasted the molecules AHEAD of ISON by now. Interesting. I await NASA/CIOC explanation. 

I believe this image might show that the trailing 2 tails of ION’s and Dust, are replaced by a “cone” of particles being blasted out and away from the point of disintegration. Could this be what we are seeing? i.e. what leaves the “black circle”  is quite different from what entered. 

Comet ISON – Material for Students

In celebration of this event (hyperbolic, sun-grazer) which occurs only once or twice a century, I have put together a FREE eBook called “COMET ISON”. It presents some unique perspectives which should give students a broader understanding of COMETS and especially these rarer HYPERBOLIC sun-grazing comets like ISON.

In Summary, the material is freely offered for students to use in any papers they are writing.

The FREE eBook asks 9 basic questions :  

  1. Is ISON a long period comet on a hyperbolic orbit?
  2. Is ISON from the Milky Way Galaxy whereas typical short period comets like Halley, are from the Sagittarius Galaxy like our sun (+ its planets, comets and asteroids)?
  3. Will ISON explode and generate the most amazing tail visible to the naked eye in December and January? (28 Nov 2013 – looks like it has disintegrated). No sign yet of material coming round the Sun. 
  4. Will particles be blown on the solar wind to Earth and affect satellite communications or the Northern Lights? 
  5. Will ISON deliver to Earth’s atmosphere a set of new viruses and bacteria as predicted by the Panspermia Hypothesis? 
  6. Are massive hyperbolic exocomets like ISON the source of the earth’s water? 
  7. How lucky are we that earth was not on the trajectory of ISON? 
  8. Will we ever be able to detect, track and divert such hyperbolic comets?
  9. What experiments are planned over the next 2-12 months? Detection of complex molecules (even life itself?)

Click here to download and enjoy this FREE eBook.

William E. Smith November 2013

It is made available under the “Creative Commons” philosophy.

Paul Wiegert University of Western Ontario predicts possible Jan 12, 2014 meteors?

Veteran meteor researcher Paul Wiegert of the University of Western Ontario has been using a computer to model the trajectory of dust ejected by Comet ISON, and his findings suggest that an unusual meteor shower could be in the offing.

“For several days around January 12, 2014, Earth will pass through a stream of fine-grained debris from Comet ISON,” says Wiegert. “The resulting shower could have some interesting properties.

According to Wiegert’s computer models, the debris stream is populated with extremely tiny grains of dust, no more than a few microns wide, pushed toward Earth by the gentle radiation pressure of the sun. They will be hitting at a speed of 56 km/s or 125,000 mph. Because the particles are so small, Earth’s upper atmosphere will rapidly slow them to a stop.

 

“Instead of burning up in a flash of light, they will drift gently down to the Earth below,” he says. 

Best site to keep current :  Click here

 

Waiting for Comet ISON

So now we have three hypotheses for the COMET ISON as it approaches and passes the perihelion over the next 28 days (Nov 28th is the date) : 

  • NASA Frozen Ice : predicts extreme temperature and pressure might (50-50) cause disintegration of the shell and evaporation of the core. Good news : the 2 tails do not intersect earth’s orbit even after any explosion.
  • Hoyle Wickramasinghe’s Panspermia Model : predicts “seeds of life” carried in comet. Might be possible to test in stratosphere when earth is closest to ISON trajectory in late January. BUT if COMA does “explode” it is likely any matter is vaporized.
  • James McCanney’s Plasma Discharge Comet Theory : predicts serious effects on the sun, the earth’s magnetic field and the sun’s own solar wind. Potential effects on earth/satellite communication is unknown but worrisome.

Question from BCMETEORS.NET to STScI OPOPlease could you comment on the best time amateur meteor watchers should look for meteors from ISON’s dust tail.

Answer :  Hello Bill: One study indicates that there will be very little chance of meteor activity related to Comet ISON:  http://arxiv.org/abs/1310.3171

Nevertheless, it looks to me like possibly the best chance to look for any meteor activity would be in mid-January, when the Earth passes “near” where the comet had travelled earlier in its orbit (NB the earth never passes directly through the path of the comet).  These simulations nicely show the path of the comet and the planets through the Solar System.  Zolt Levay STScI OPO  http://svs.gsfc.nasa.gov/vis/a010000/a011200/a011222/

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Question : Hi Zolt : last quick question : The missing possibility (at least from the abstract) is what would be the affects of  disintegration (estimated at 50%) . Depending on how this might occur? I assume it would be caused by  gravitational stress (+ heat) on the shell. If the shell shatters the resulting “explosion” surely would be similar to the Chelyabinsk explosion (even though this was caused by air friction and heat). When this occurs would not energy (and particles – water etc)  dissipate initially spherically and then conically? Or away from the sun? or what?

Answer : Hi Bill, I’m not an expert in this area, so I can’t comment in detail on the mechanics of exploding comets or meteors.  However, yes I suppose that if the comet disintegrates, I suppose the material would drift apart and be spread over a larger volume, whether its explosive or more gradual.  I wouldn’t be able to estimate how much larger.  

If the comet does disintegrate as it approaches the Sun, those smaller pieces would heat more quickly and be much more likely to completely dissipate.  I guess that material has to go somewhere, but much of it will totally vaporize — becoming gas instead of pebbles — and be spread over an extremely large volume at very low density, and with little chance of intersecting with anything else in the Solar System.  Seems a little anticlimactic I admit.  Nevertheless, it certainly doesn’t hurt to look for extra meteors. 

Zolt, STScI OPO

(Sen) – One of the most eagerly awaited comets in history is livening up as it heads for its rendezvous with the Sun later this year.

Comet ISON has already been monitored by the Hubble Space Telescope and the Swift satellite as it races in between the orbits of Jupiter and Mars. Now another orbiting observatory, NASA’s Spitzer Space Telescope, has taken its own close-ups.

Images newly released show the comet, officially labelled C/2012 S1, as it appeared with Spitzer’s infrared array camera on 13 June when it lay about 500 million km from the Sun. It was clearly already fizzing with activity.

The picture on the left, taken at a wavelength of 3.6 microns, shows a tail of fine rocky dust being ejected from the comet’s head and being blown away by the pressure of the solar wind.

UK astronomy populariser Stuart Atkinson has setup a blog, Waiting for ISON, with observing advice and star maps to help people view the comet. He told Sen: “These are fascinating observations from Spitzer. We’re all crossing our fingers that this is a good sign and that ISON will become very active as it approaches and rounds the Sun.

“Hopefully it means ISON will captivate us all in early December, but of course everyone should just try and stay calm and not get too carried away. ISON might dazzle and delight us, or disappoint and depress us, it’s too early to say yet, no matter what anyone tells you.

“It’s often said that comets are like cats but I think they’re more like politicians: sometimes they promise us the world at first, to get our attention, and then let us down! But let’s hope for the best!”

The comet has an orbit that is close to a parabola, which suggests it may be on its first journey into the inner Solar System from the Oort cloud of icy bodies that is thought to surround it. It has the consistency of a dirty snowball, being made up of dust and gases such as water, ammonia, methane and carbon dioxide left over from the formation of the planets 4.5 billion years ago.

Cranbrook College Meteor – Aug 2013

Hot News from Rick Nowell:  Cranbrook College of the Rockies meteor camera picked up a very long and slow meteor graze or something re-entering the atmosphere.   Slow, it takes 30 seconds to cross the sky.  That happened on Tuesday 6 Aug 2013 at 4:52 am Mountain Daylight Time (or 10:52 Universal Time).

[cid:f94223bc-ecaf-4a31-a8c4-36379206b130]

 

 

This is a composite photo with the 30 seconds of video frames superimposed.  This has been enhanced in IRIS by subtracting a camera dark frame to remove background hot pixels, offsetting 10 from the bottom amplitudes and applying an adaptive filter to remove some hiss, then taking a logarithmic stretch to bring up background stars, like Vega, Capella and Jupiter.  (Altair seems too low when I compare to a starmap though).  Note two reference points, a beacon to the North at Alt/Az (1.0, 3.1º), and another beacon to the NW at (3.0º, 309º).

The object kind of sputters and leaves a short smoke trail behind it.   Fast at first, then slowing down.  But no chunks falling off.  It comes out of a thin cloud haze on the West, and vanishes in a band of clouds to the Northeast, into the morning twilight glow.  But the sky appears clear in between. 

Thin clouds could make it appear to sputter, but the sky appears clear overhead.  Here in the attached SlowGraze_6Aug2013_600s.PNG I composited 600 seconds of video trying to enhance cloud structure.  The object passes between two bright stars, Deneb and Vega.  Capella is visible over the vent,  but the rest of the dots are hotpixels.  (See attached Mask_Boundary Hotpixels.JPG).  You can see Jupiter rising in East, close beside the vent.

 

[cid:bdb42d6f-a9df-4450-9766-9cf037f1a95f]

(We put the camera beside the vent to shade it from light from some windows to the East.) Jeff Brower’s meteor camera in Kelowna also picked it up.

Esko Lyytinen in Finland tells Jeff that it has been uploaded to a number of websites, even one in Japan, and Jeff says it has received attention in the press.

For the video see:

http://skysentinel.nmsu.edu/allsky/viewer/798783

http://lunarmeteoritehunters.blogspot.jp/2013/08/bc-canada-long-duration-fireball-meteor.html

College of the Rockies, Cranbrook, BC, Canada  49°31’03″N, 115°44’37″W, 940m

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Hi all, Esko Lyytinen, of Finland, was once again kind enough to work on our images overnight. He has a preliminary result and he does emphasize he will be refining his modelling once he receives Rick’s cvs file for the event. That will hopefully determine if the meteor skipped back into skip or entered earth’s lower atmosphere. If we hear from the Albertan cameras, then we may have a much clearer picture of the final path.  I did send Rick’s lat/lon/el to Esko so that will refine the original data. So with those caveats here is what Esko came up with. (I quote with his permission):

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Analysis from Finland

Jeff,  I calibrated your camera by means of then stars. And I measured 15 mutually timed positions (of the fireball) in the one second images, with a time span of 16 s ( two missing in between, because not well measurable).

As to the Cranbrook camera coordinates, I may not have these as accurate. I have these: 0.427 km,    115.7 W ,  49.6 N .
And as judged from the decimals count, these are only approximate.

I have these early results of the fireball. The radiant azimuth is 230.9  and elevation 4.2 . The reference horizon and meridian for these is 118.0 W, 49.5 N  (not so fare from the beginning, rought 70 km after this) .
The entry velocity is 17.1 km/s.

It came in your camera at the height of 85.6 km and to Rick’s camera at 82.0 km. The last measured in your camera is at 64.4 km and Rick’s 58.7 km.

Because going away, the velocity near the end will not be accurately derived near the end. This data would even give some negative deceleration, which of course can not be true (but may actually be close to zero, mening quite a big meteoroid). If getting from Rick’s camera timed data also, might tell this better.

The most low “point” of the track would be maybe 10 seconds after last seen in Rick’s camera. It depends on the deceleration if the escaped back to space or not. Because no deceleration is visible in your data, I think it maybe probable that it did escape back to space. It may have been quite big (?)

As told, the precise coordinates of Rick’s camera are desirable.  And if this would allow for internally timed could probably tell better on the velocity near the end. I see the video in the net, but if timed data does not exists in a more concise form, then the original video would be desirable.

 

Great work Esko and thanks from everyone at BCMeteors.net,  from Jeff Brower, BC Canada