Comet C/2012 S1 - ISON

Well I am actually referring to something solid, the SWIFT image from January, but it might be possible that they faked it exactly to get guys like me all worked up over nothing and distracted from the real threat, whatever THAT may be.
But my ultimate question is related to the way they approach this thing from the start.

This is from the image's accompanying article:
"While the water and dust production rates are relatively uncertain because of the comet's faintness, they can be used to estimate the size of ISON's icy body. Comparing the amount of gas needed for a normal comet to blow off dust at the rate observed for ISON, the scientists estimate that the nucleus is roughly 3 miles (5 km) across, a typical size for a comet. This assumes that only the fraction of the surface most directly exposed to the sun, about 10 percent of the total, is actively producing jets."


So, they're actually trying to measure it, but in the whole article there's no mention of the only obvious thing in the image: the comet's comma's size. To me, that's fishy. Why don't they say how big it is? I mean, at a distance of 5.4 AU from the Sun, that's one hell of a comma!
 
Revolucionar said:
So, they're actually trying to measure it, but in the whole article there's no mention of the only obvious thing in the image: the comet's comma's size. To me, that's fishy. Why don't they say how big it is? I mean, at a distance of 5.4 AU from the Sun, that's one hell of a comma!

Hello Revolucionar,
How do you calculate the diameter of the coma from that image? Someone may have taken the trouble to do it but without reviewing the method, there is no way to be certain of it. We have just that jpg image on the website. You can notice that the coma has almost the same angular size as the stars (which are supposed to be point-sources). That means that its image is dominated by the point-spread-function of the optical system. On the other hand, the 5.5 minute exposure image is tracking the stars, another parameter to take into account when performing the deconvolution of the image, which is not trivial. Even if one has access to the raw data, the operation is not easy at all. I think the diameter from unresolved images is just a red-herring and that one has to concentrate on verifiable data and not to be taken by all the nibiru nonsense surrounding this or that comet.
 
Now, that's a good point... Finally! I think it partially resolves the issue, but then the question remains: why aren't they giving a scale of reference for the newer, better resolution pictures, taken at closer distances, and why are they making them with that stupid layering method which ends up with parallax displacement and further allows for the nutcases to speculate how it's a mothership, or the Nibiru system, or whatever.
Can't they just present us with a simple high-resolution image with a scale of reference? It's all said if you know that the best picture up until now comes from an amateur astronomer with a backyard telescope, who was, BTW, the first to see it come around the Sun.
I have a feeling from the beginning that they might be adding fuel to the fire of doomsayers, but i don't know why.
 
First of all, when the Hubble unstacked data have been published, some amateurs did the stacking (combination images taken at different times) right and others did it wrong. The Nibiru youtube videos showed those that were made wrongly (with the parallax thingy).
The latest ground-based images have been taken mostly by amateurs because the comet is still at a small elongation from the Sun, you can't do that with bigger telescopes without taking a huge risk of damaging very expensive instruments, in addition to restrictions related to the altitude of the object above the horizon at the most favorable window of observation. There are also other reasons related to photometry and instrument calibration (every instrument will see more or less of the coma/tail). Image processing is a delicate operation and if memory serves me well, some issues have been discussed in this video: _https://www.youtube.com/watch?v=K5ZY_hzxz9c
Putting a scale on an image is not a standard operation. Usually the observer indicated the scale with something like X arcseconds/pixel if he/she has taken the time to calibrate the image on a nearby double-star. But usually you do that when your object is near the zenith where the distortion due to the atmosphere is minimal. In astrophotography it doesn't matter because all you want is to have pretty images :)

With ISON, things become interesting in October. For the moment there is too much speculation that is irrelevant, especially from the disinformation front. OSIT
 
As if all the fear-mongering about C/2012 S1 wasn't enough, now we've got that old disinfo site, Sorcha Faal, rumbling about the dreaded "planet killer" coming in 2014.

The Federal Space Agency (ROSCOSMOS) is warning in a new report to President Putin today that Russian space defenses should be “immediately activated” and that the 5,000 new civil population bomb shelters completed this past year be “urgently stocked” after scientists confirmed that newly discovered Comet C/2013 A1 (Siding Spring) is, indeed, a “planet killer” and has Mars “in its sights.”

According to this report, Mars-bound Comet Siding Spring was discovered by Rob McNaught on 3 January at Siding Spring Observatory in Australia after which all of the information relating to this threat was turned over to Project Wormwood run by IPS Radio and Space Services and established at Learmonth Solar Observatory to participate in the first two phases of Planetary Defence.

IPS Radio and Space Services is the Australian Space Weather Agency, providing advice to customers in the Australasian area on the near-space environment, and the effects it has on communications, navigation, satellite operations, and other technological systems, whereas the majority of Project Wormwood activities are follow-up astrometry (position measurements) that are required to obtain precise orbits for space objects (asteroids/comets) that have previously been discovered by other programs.

US scientists report that they expect Comet Siding Spring’s closest approach to Mars to occur on 19 October 2014, at about 11:45AM. PDT (18:45 GTM), which their latest orbital plot places its closest approach to Mars a little farther out than previously estimated — at about 117,000 kilometers (73,000 miles) from the surface of the Red Planet.

Richard Zurek, chief scientist for the Jet Propulsion Laboratory's (JPL) Mars Program Office and project scientist for NASA's Mars Reconnaissance Orbiter (MRO), had previously warned that if Comet Siding Spring did impact Mars it “could be a huge, global event” and further warned “we will have to start thinking about what precautions we should take.”

Where US safety measures would include positioning their orbiters so that they are on the other side of Mars at the time of comet impact, this report continues, the “lethal potentiality” of Comet Siding Spring cannot be underestimated, specifically as its size, 50 km (31 miles) would result in an upper limit energy of impact that could reach 20 billion megatons and leave a crater measuring 44 km (338 miles) in diameter.

The greatest danger to Earth should Comet Siding Spring impact Mars, ROSCOSMOS experts state in this report, would be the massive debris field ejected into space which would then plummet towards the Sun and eventually crossing our planets orbit.

While it is gratifying to me to see a few others taking the comet threat seriously in the past year, since I've been hammering on this topic for 16 years or so, I'm not sure I like the direction it is taking. Putting this kind of thing out on disinfo sites only makes it ridiculous. And there is a very real danger.
 
Meanwhile, don't know if these links have been posted here already, but a couple of articles about C/2012 S1:

http://earthsky.org/space/big-sun-diving-comet-ison-might-be-spectacular-in-2013

Comet C/2012 S1 (ISON) has been the most talked-about comet of 2013. When discovered in late 2012, it was said to have the potential to become a striking object visible to the eye alone around the time of its perihelion – or closest point to the sun – on November 28, 2013. People started saying Comet ISON and comet of the century in the same sentence. In June and July 2013, Comet ISON was behind the sun as seen from Earth, but when it was recovered in early August, it wasn’t as bright as hoped. What will happen with Comet ISON in the remaining months of 2013? Comets are notoriously unpredictable, but it’s safe to say that many are waiting to see if Comet ISON will sizzle … or fizzle. ...

skyandtelescope.com’s senior editdor Alan MacRobert:

Comet ISON is about two magnitudes (six times) fainter than it should be compared to the calculations that first led astronomers to predict it would become a grand naked-eye sight before dawn in early December. The comet could still turn out to be fairly good, or it might never reach naked-eye visibility at all.

Skyandtelescope.com editor-in-chief Robert Naeye:

Comets are notoriously fickle, unpredictable objects, so I’m not giving up hope just yet. But these latest observations should temper expectations. We’ll simply have to wait and see how the comet develops in the months ahead as it ventures closer and closer to the searing heat of the sun.

Since Bruce Gary’s great capture of the comet on August 12, other astronomers have also captured Comet ISON on film, also showing that it is not living up to expectations.

http://www.reuters.com/article/2013/07/30/us-space-comet-idUSBRE96S16U20130730

Astronomers slated to meet this week to discuss observing plans for Comet ISON may not have much to talk about. The so-called "Comet of the Century" may already have fizzled out.

"The future of comet ISON does not look bright," astronomer Ignacio Ferrin, with the University of Antioquia in Colombia, said in a statement on Monday.

Ferrin's calculations show the comet, which is currently moving toward the sun at 16 miles per second, has not brightened since mid-January. That may be because the comet is already out of ice particles in its body, which melt as the comet moves closer to the sun, creating a long, bright tail.

Another theory is that the comet is covered in a layer of silicate dust that snuffs out water vapor and other gases that brighten the comet.

"Comet ISON has been on a standstill for more than 132 days ... a rather puzzling feat," Ferrin wrote in a paper submitted to the Monthly Notices of the Royal Astronomical Society and posted online at the archival site arXiv.org.
 
The great Telescope Canary (GTC) detects strange anomaly of Comet ISON

In the photos, you see the main body at the base of another small following. Astronomers do not know what it is. The report prepared by researchers of the Gran Canarias Telescope (GTC), said also that the ISON Comet does not increase in size as expected. Whenever there are problems, becoming more often are related to the ISON astronomers Comet nothing do but write and abnormalities of the records never seen before in a Comet, and among these it is mainly due to the fact that: Ison does not behave like a space object, or a Comet, but it is another thing and who officially do not want to admit it or declare the current public institutions. So, as mentioned above, the Ison is not only a Comet, but a mysterious object that science does not know how to interpret.
Writing Segnidalcielo (traduction Bing)

 
Anthony said:
The great Telescope Canary (GTC) detects strange anomaly of Comet ISON

In the photos, you see the main body at the base of another small following. Astronomers do not know what it is.

Can you provide a link to the site where this is reported?
 
It's from this facebook channel, the person that did the extreme weather comilation, you have to scroll down a bit though.

https://www.facebook.com/pages/HawkkeyDavisChannel/440679762635468

It's related to this: http://www.youtube.com/embed/ME2WXjRB9cA

http://www.youtube.com/watch?v=PvS6V8B349M
 
There is this article from 19 of September, but no mention of 1680.

More ISON Craziness: Tales of Popes, a Prophet and a Comet
_http://www.universetoday.com/104784/more-ison-craziness-tales-of-popes-a-prophet-and-a-comet/

There’s an astronomical tall tale from the Middle Ages that seems to get recycled as factual every time a “great” comet rolls around. This week, we thought we’d look at a story that just won’t die, as well as a new twist in comet conspiracy that’s rolling around ye’ ole ‘Net.

We’ve debunked the current craziness surrounding ISON recently, but apparently our work isn’t finished! Comets seem to bring ‘em out of the woodwork. Today, we’ll discuss how that old prophet of doom Nostradamus may have “predicted” Comet ISON being part of the ‘end times,’ but first, let’s look at an astronomical tale of the past. Did a pope really excommunicate the most famous of all comets?

The mid-15th century was a trying time for Medieval Europe. The Black Death had decimated the population of Europe a century prior, and the armies of the Ottoman Turks were advancing from the east. A bright comet could only bear ill will in the minds of the superstitious.

It was into this setting that Pope Callixtus III came into power in 1455. Callixtus was the first of two popes fielded by the Spanish Borgia family, which would later include his nephew Rodrigo who became Pope Alexander the VI, as depicted in the Showtime series The Borgias.

A fine the apparition of Halley’s Comet occurred in June and July 1456. Belgrade was to come under siege by the Ottoman Turks from July 4th to 22nd of that year, and the Fall of Constantinople on May 29th, 1453 to Mehmed II was still fresh on everyone’s mind.

Astronomical signs and omens were a hot topic as well. The partial lunar eclipse of May 22nd, 1453 was seen by many to have fulfilled prophecy that an eclipse would mark the fall of Constantinople. Of course, there are from 4 to 7 eclipses that can be seen on any given year, and lunar eclipses are visible from the entire moonward facing side of the Earth. It’s not too tough to find one to fit any given bill of gloom and doom.

Keep in mind, Halley’s Comet wasn’t even identified in the 15th century as the same comet that was returning once every 75.3 years. That fact wouldn’t be uncovered until Edmund Halley successfully predicted the return of the comet that now bears his name on Christmas Day 1758.

Halley’s Comet would’ve been a spectacular sight in the early summer of 1456, unfurling a tail that was said to have been 60 degrees long and spanning the constellations of Cancer and Leo. The brilliant comet would’ve been a conspicuous object for up to three hours after sunset, and it’s certain that observers around the Mediterranean, including a Rome-based pope would’ve seen it.

But did the pope actually excommunicate the comet to assuage the fears of the European populace of an invasion from the east?

While a quixotic story, the idea that a pope could’ve banned a heavenly body from salvation is apocryphal as best. The Papal Bull issued by Callixtus III on June 29th, 1456 called for prayers and penance and the ringing of church bells in light of the cruelty visited upon Eastern Europe by invaders from the east, but makes no mention of the comet. In fact, no primary source for the tale exists.

The story seems to have gotten its start with a historian named Platina, who wrote a biography of Callixtus III in 1471. Here we find the appearance of:

“A hairy reddish comet appearing for several days… Callixtus, in order to avert the wrath of God, ordered processions to be held…”

No out right excommunication per se, but the Pope and the comet were now forever linked in the eye of history.

French mathematician and astronomer Pierre-Simon Laplace later gave the excommunication tale a boost in the late 18th century, and further embellishment followed from astronomer François Arago writing in 1832.

Keep in mind, these are historical works written down some years after the fact, often translated from Latin to French to English—ideas such as LaPlace’s “conjurer la comete” can easily come across as to “exorcise” or “excommunicate” a comet. Also, political satire of popes, both alive and dead, was common after the start of the Protestant Reformation. Halley’s Comet also made a fine apparition in 1835, and Arago may have been looking for something to captivate the public with in anticipation.

But although this story was debunked over a century ago, it still makes its rounds. None other than Carl Sagan repeated the excommunication story in his book Comet (sorry Carl!) although he also notes that the tale is apocryphal. Although the story of the excommunication of Halley’s Comet has been debunked time and again, a search of the Internet reveals about an even split between the credulous and the skeptical.

But there is also a current mythos being born around Comet ISON, Pope Francis and Nostradamus on ye ole web. For the most part, it has to do with — you guessed it — the end of the world. As per the usual, great comets are harbingers of catastrophic events. Combine the words of Nostradamus with the fact that 2013 has been hyped as “The Year of the Comet,” along with Pope Benedict’s unusual resignation, and that equals The End of Time.

If you don’t believe me, search of Comet/ISON/Pope and see what turns up. The gist of the prophecy cites a quatrain stating that:

“the great star for seven days shall burn

So nakedly clear like two suns appearing

The large dog all night howling

While the great Pontiff shall change his territory.”
Of course, the quatrains of Nostradamus, like all prophecies, are suitably vague enough that they could be interpreted almost in whatever fashion suits the reader. And again, we’re looking at the old 16th century French translated into modern English.

And like eclipses, there are a handful of comets every year. Most reach binocular visibility, and a few may go on to become visible to the naked eye. We’ve already had two comets that crossed this threshold this year, comet C/2011 L4 PanSTARRS and C/2012 F6 Lemmon.

And Comet ISON’s “greatness” is still very much in question. Its currently only at 12th magnitude and probably won’t be a naked eye object until at least early November. And it certainly won’t have the appearance of a second Sun!

I’ll leave it to the armchair predictors of comet doom to decipher what “the large dog howling” even means. The chief logical fallacy evoked by the adherents of Nostradamus is what is known as retrofitting— it’s easy to take a cryptically predicted disaster and find an earthquake, eclipse, and yes, even a comet that falls roughly near the given date.

Of course, if ISON kicks into high gear, then we could really be in for a grand show, along with an accompanying upswing in comet hysteria. And thus, the tireless vigilance against comet-mania continues. Hey, we’re all after “link juice” and the almighty SEO, right? Of course, the real harm comes when something like the 1997 Heaven’s Gate mass suicide, inspired by rumors of an alien spacecraft following comet Hale-Bopp occurs.

In short, enjoy the show as ISON approaches, read the online tales of popes and comets past… but as rapper and surreptitious promoter of skepticism Chuck D of Public Enemy implores us, don’t believe the hype.

Maybe we’ll finally be an enlightened and rational species when Halley’s Comet pays us a visit again starting in the summer of 2061 through the spring of 2062!

-For an exhaustive look at the myth of the excommunication of Halley’s Comet, Read An Historical Examination of the Connection of Callixtus III with Halley’s Comet published in 1910.

-To see a (mostly) woo free version of the current Comet ISON versus Pope Francis mythos, (with quatrains) check out this article from news.com.au. Hey, we sift through woo so you don’t have to!
 
34j3.jpg


May be a single comet discharging at two separate points.

Imagine something like this:

halley_hmc_small.gif
 
The image with two spots is not dated, hard to tell. The second spot (to the right) is very likely a star in the background (behind the comet) unless the configuration persists at different dates.

Edit: grammar
 
mkrnhr said:
The image with two spots is not dated, hard to tell. The second spot (to the right) is very likely a star in the background (behind the comet) unless the configuration persists at different dates.
Yeah it's probably that.
 
Here's an interesting morsel of information which appeared on Google+ yesterday. Not sure if it is significant but you may enjoy it nevertheless.
Check out the video attached to the post.

Slooh Space Camera said:
Comet ISON Has A Traveling Companion
_https://plus.google.com/108176209664415419112/posts/2rxWUULWtwR

Comet C/2012 S1 (ISON) wasn't alone in the pre-dawn skies above Slooh's Canary Islands Observatory tonight. Accompanying Comet ISON was the huge asteroid "433 Eros" - the second largest Near-Earth Asteroid. Eros was traveling in roughly the same direction as ISON, but at a slightly faster apparent speed, and can be seen above and to the right of the comet. Slooh Members watched the images come in from the observatory in real-time, and immediately spotted the second object moving between successive images.

This time-lapse of five images, created this morning by Paul Cox using Slooh's online robotic telescopes, shows the two objects as they speed through the inner solar system.

Paul Cox is Slooh's Lead Tech and Outreach Coordinator, and has been running a series of regular online Comet ISON update shows at slooh.com. The shows always include live images of Comet ISON during the broadcast - what a pity there wasn't a show tonight!
 
Back
Top Bottom