Tag Archives: Comets

The Younger Dryas Event

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Scientists Agree: Younger Dryas Impact Event Wiped Out Ancient Civilization | Ancient Architects

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Via Ancient Architects

The Earth was hit by a fragmented comet around 13,000 years ago at the end of the Pleistocene Era and scientists are now starting to agree.

A new research paper has been published in Scientific Reports regarding an ancient civilisation in what is modern-day Syria that was wiped out by the cataclysm, as academics finally come round to the idea that yes this event did happen.

Even the sceptic Michael Shermer, who famously debated Graham Hancock on the Joe Rogan podcast has tweeted Graham saying:

“Ok Graham, I shall adjust my priors in light of more research like this, and modify my credence about your theory.”

The evidence always spoke for itself for a lot of people, but it’s positive to see him address Graham in a public manner like this.

So what have the scientists discovered? Well, remnants of glass have been found that could only have been created during a high-impact event. Other minerals such as chromium, iron, nickel and others were discovered too, all of which form at temperatures higher than 2,200 degrees, according to a statement from the University of California-Santa Barbara.

The site the discovery was made is known as Abu Hureyra, which was abandoned around 5,000 years ago.

The glass finds are believed to have been formed from the instantaneous melting and vaporization of regional biomass, soils and floodplain deposits, followed by instantaneous cooling. This is really only common during impact events.

Graham Hancock and others such as Randall Carlson have long said that it was likely a fragmented comet, and that is what the scientists are saying who are analysing the Syrian finds. A single, major asteroid impact could not have caused the widely scattered material discovered at Abu Hureyra and the experts say that it is more likely a fragmented comet.

The Younger Dryas Event is what caused a large megafaunal extinction, seeing the end of woolly mammoths, species of bison, American horses and camels, and giant sloths. It also saw the end of the North American Clovis culture.

The evidence is there in the field and it continues to stack up. Two years ago we read about reports of a 19-mile wide crater in Greenland that could be related to this cataclysmic event and in October 2019, a study was published that said there was a mini ice age 12,800 years ago that was caused by an impact event.

But at the beginning of this mini ice age there were huge levels of burning and now we know that Abu Hureyra was abruptly destroyed from what can only be an impact event. We have new direct evidence of the disaster, together with tons of data from around the world. History is finally being re-written!

All images are taken from Google Images and the below sources for educational purposes only.

Sources:
https://nypost.com/2020/03/10/giant-a…
https://www.ancient-origins.net/news-…
https://www.nature.com/articles/s4159…

from:    https://sacredgeometryinternational.com/scientists-agree-younger-dryas-impact-event-wiped-ancient-civilization-ancient-architects/

Comet Linear Flyby Soon to End

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See a green comet come close to Earth next week: Stargazers in northern hemisphere could be treated to a stunning show

Comet Linear is 100 times brighter than astronomers had expected
Due to moon-filled skies, you may need binoculars to get a good view
Sky watchers will need to be outside at least 1.5 hours before sunrise
It will be roughly in line with Mars and Saturn on morning of March 29th

By Ellie Zolfagharifard For Dailymail.com

A bright green comet is about to come into view for sky watchers in the northern hemisphere.

The icy space rock, dubbed Comet Linear, will emerge from next week and be around 100 times brighter than astronomers had expected.

Sky gazers in the southern hemisphere, were treated to view of the comet earlier this week, after it passed Earth at 3.3 million miles away.

HOW TO SEE IT

Go to an area with low light pollution away from any cities or towns.

You will need to be out at least 1.5 hours before sunrise,

The comet is moving between the constellations Sagittarius and Scorpius. This is in the southern part of the sky.

The planets Saturn and Mars are in this part of the sky as well.

They and the bright star Antares will be the first things you notice, forming a distinctive triangle a little smaller.

The comet is climbing to the left of this trio.

You may need the help of binoculars, as the moon light will could obscure your view.

Currently, Comet Linear is moving rapidly into view from the northern hemisphere. But due to moon-filled skies, you may need binoculars to get a good view.

Sky watchers will need to be out at least 1.5 hours before sunrise, in a location as free from light pollution as possible.

The comet is moving between the constellations Sagittarius and Scorpius, which is in the southern part of the sky before dawn.

Each morning the comet will be higher up with respect to the surrounding stars.

The planets Saturn and Mars are in this part of the sky as well.

They and the bright star Antares will be the first things you notice, forming a distinctive triangle a little smaller than your clenched fist held at arm’s length, according to Sky & Telescope.

The comet is climbing to the left of this trio. It will be roughly in line with Mars and Saturn on the morning of March 29th and along a line connecting Saturn and Antares on March 31st.

‘Don’t expect Comet Linear to be obvious with a long tail,’ explains Sky & Telescope Senior Editor Kelly Beatty.

‘Its light isn’t concentrated in a single point but instead is spread out in a soft round glow, larger than the Moon but many thousands of times dimmer.’

Comet Linear has a greenish colour caused by molecules of diatomic carbon that are fluorescing in sunlight.

However, the green tint likely won’t be evident unless you view the comet through a telescope.

Given the comet’s unexpected surge, astronomers aren’t sure how long it will remain.

READ MORE:   Comet 252P/LINEAR Soars Into Predawn View This Week – Sky & Telescope
Read more: http://www.dailymail.co.uk/sciencetech/article-3509840/See-green-comet-come-close-Earth-week-Star-gazers-northern-hemisphere-treated-stunning-show.html#ixzz448UTOQuS
Follow us: @MailOnline on Twitter | DailyMail on Facebook

Check out also:   https://www.youtube.com/watch?v=ThbuvhwWuFA

SunDiving Comet

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SUNDIVING COMET DESTROYED: The solar system now has one less comet. Earlier today, a sundiving comet discovered on Sept. 15th by Worachate Boonplod, a science writer from Thailand, passed too close to the sun and apparently evaporated. A coronagraph onboard the Solar and Heliospheric Observatory (SOHO) recorded the death plunge:

One comet went in, no comets came out. Fierce heat from the sun likely evaporated the comet’s fragile ices, transforming it into a disintegrated cloud of gas and dust.

Sundiving comets are more common than you might think. SOHO has found more than 3000 of them. Most are members of the Kreutz family. Kreutz sungrazers are fragments from the breakup of a single giant comet many centuries ago. They get their name from 19th century German astronomer Heinrich Kreutz, who studied them in detail. Kreutz fragments pass by the sun and disintegrate almost every day. Most, measuring less than a few meters across, are too small to see, but occasionally a bigger fragment like this one attracts attention.

from:    spaceweather.com

Non-Group Sun Grazing Comet

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UNUSUAL COMET DIVE-BOMBS THE SUN: Astronomers are puzzling over a comet that passed “insanely close” to the sun on Feb. 19th. At first glance it appeared to be a small object, not much bigger than a comet-boulder, doomed to disintegrate in the fierce heat. Instead, it has emerged apparently intact and is actually brightening as it recedes from the sun. Click to view a post-flyby movie recorded on Feb. 20th by the Solar and Heliospheric Observatory (SOHO):

Unofficially, the icy visitor is being called “SOHO-2875,” because it is SOHO’s 2,875th comet discovery.

Karl Battams of the Naval Research Lab explains what’s odd about SOHO-2875: “It’s a ‘non-group comet,’ meaning that it does not appear to be related to any other comet or comet family that we have on record.”

Most comets that SOHO sees belong to the Kreutz family. Kreutz sungrazers are fragments from the breakup of a single giant comet many centuries ago. They get their name from 19th century German astronomer Heinrich Kreutz, who studied them in detail. SOHO-2875, however, is not one of those fragments.

“Non-group comets like this appear a few times a year, so in that sense it’s not too unusual,” continues Battams. “But this one is relatively bright. The big question most people will have now is, Can I see it, or will I be able to see it, from Earth? At first I thought the answer was no. But I am very pleasantly surprised–shocked in fact! The comet has brightened dramatically and now is sporting an increasingly impressive tail. Visibility from Earth in a few weeks is no longer out of the question, although I still wouldn’t put money on it.”

“I’ll continue to tweet updates on my twitter.com/SungrazerComets feed, so folks can follow along there too.”

from:    spaceweather.com

Celestial Highpoints of 2014

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Most Interesting Celestial Events of 2014

astronomical events 2014What astronomical phenomena will be observable to people in different parts of the Earth this year?

2014 will be saturated with celestial events in respect of comets and asteroids, but less intense and interesting in respect of eclipses.

First on the list is a lunar eclipse which will occur on April 15 and will last 1 hour 19 minutes. Only the inhabitants of North and South America will be able to see the complete eclipse.

In 2 weeks after that, on April 29, a partial solar eclipse will take place when the Moon will cover the sun only partially. The eclipse will reach its maximum phase in Antarctica and will be observable to the inhabitants of Australia and Tasmania. The eclipse will last only 6 minutes.

The next eclipse will be a full moon, which will take place on October 8. This time, the eclipse will be seen to the inhabitants of North America, the eastern part of Russia, Australia, New Zealand and some other Pacific islands. This eclipse is interesting because during the total phase the Moon will cover Uranus.

Last eclipse of the list is a partial solar eclipse, which will happen on October 23 and will be visible in North America and eastern Russia.

The brightest asteroid of this year will be Vesta, one of the largest asteroids in the main asteroid belt. Its brightness is expected to peak in April when it will be visible with the naked eye. The second brightest asteroid will be Pallas, which is larger than Vesta and ranks first in size among all the asteroids in the main asteroid belt. Pallas will be seen later this month. Among the other most interesting asteroids, Hebe and Juno are worth noting.

Some sources mistakenly attributed Ceres to the asteroids and included it in the list above. However, Ceres had been considered an asteroid till August 24, 2006, when it was classified as a dwarf planet.

The bigger an asteroid is, the more sunlight it reflects. However, the brightness of an asteroid is heavily dependent on the albedo (reflectivity characteristics of its surface), which in turn is determined by the composition of its constituent species. For example, the asteroid Vesta reflects 4 times more light than the dwarf planet Ceres because of the high albedo of the surface and is the most visible asteroid in the sky, which often can be seen even with the naked eye.

The brightest comets will be 154P (P/Brewington), C/2011 W3 (Lovejoy), C/2012 X1 (LINEAR), C/2012 K1 (PanSTARRS) and C/2013 A1 (McNaught). The list may vary depending on the expected increase in brightness and the discovery of new comets.

from:    http://www.learning-mind.com/most-interesting-celestial-events-of-2014/

ISON & Encke Movie

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UPDATE: New ISON and Encke Movie

Submitted by Karl Battams on Fri, 11/22/2013 – 15:52
Comets C/2012 S1 (ISON) and 2P/Encke continue to race through the solar system in this updated sequence! CLICK TO ANIMATE! [Image Credit: Karl Battams/NRL/NASA-CIOC]

Here’s the latest awesome movie I have of Comet’s ISON and Encke in the NASA STEREO-A HI-1 field of view! Click the image opposite and enjoy (it’s about 4.7MB so might take a moment to load)

I’ll spare you a repeat of the details I gave yesterday, and instead will just encourage you to read that blog post, in which I describe some of the background info here, including why this movie is so amazing and why it’ll just keep getting better!

There are a couple of new things I want to say here though. First I received a good question via Twitter that was along the lines of “where exactly is the Sun relative to all this?“. I briefly mentioned it yesterday but it’s worth elaborating on a tad. The Sun sits outside of the field of view of this camera, off to the right as you look at this movie. What I’m not showing you here (purely in the interest of small file sizes) is the full field of view of this camera. Here is a full field image, complete with a CME that appears to be blasting towards the comets… Will it hit them? We’ll have to wait and see, won’t we!

Second, I want to make a note of some interesting dynamics in ISON’s tail. You’ll see that Encke has kind of long waves in the tail, whereas ISON’s seems almost like high-frequency “puffs”. Off the top of my head I can think of two possible reasons, though one is really speculative.

The less speculative (and most likely) is that ISON is simply in a faster stream of the solar wind. Imagine holding a flag on a slightly breezy day. The flag will waft gently in the breeze. Now imagine holding it in really strong winds. The flag will be rippling violently, but those ripples will be smaller in amplitude. We need to look at solar wind velocities in that area to be sure, but that’s the guess I’m planting my flag [unintended] into.

The more speculative one would be that maybe it has something to do with ISON’s rotation. But I really don’t think ISON is rotating that fast or we’d have detected it from the ground. I also don’t know that a fast rotation would show up like that anyway. I’m really just thinking out loud on this one. If anyone asks you, I’d definitely stick with the solar wind speed argument for now – it’s much safer.

I don’t know when I’ll next get more data to update this movie. The STEREO spacecraft are far from Earth and they don’t send down this high-res data in realtime, or anything close to it. Hopefully some point tomorrow I’ll get some more but – just to forewarn you – it can take up to two or three days sometimes. If that happens, it’s because of DSN schedule conflicts and not because of some “omg it’s aliens” reason. Let’s please save the tin-foil for making turkey this week, not hats! [That’s a Thanksgiving Holiday reference, for you non-US folks.] Spacecraft data connections are spotty but we will absolutely do our best to get what we can, when we can. Keep checking back, and follow my Twitter feed (link below) for the latest updates.

frfom:    http://www.isoncampaign.org/karl/updated-ison-encke-movie

Mercury gets a 2 Comet Fly-by

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Two Comets to Fly By Mercury

Nov. 15, 2013:  What are the odds? On Nov. 18th and 19th not one but two comets will fly by the planet Mercury.

“This is a unique coincidence,” says Ron Vervack an astronomer at the Johns Hopkins University Applied Physics Lab and a member of the science team for NASA’s MESSENGER spacecraft, “and a golden opportunity to study two comets passing close to the sun.”

On Nov. 18th Comet Encke will pass within 0.025 AU of Mercury, followed a day later by Comet ISON at 0.24 AU (1 AU is the distance between the sun and Earth, 150 million km).   The MESSENGER spacecraft, which is orbiting Mercury, will turn its sensors toward the passing comets for a point-blank investigation of both.

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A new Sciencecast video previews a rare double encounter between Mercury and two comets. Play it

The double flyby is exciting, says Vervack, but “it makes things a little crazy. We have to rush to complete our observations of Comet Encke, then do it all over again for Comet ISON. Everything is happening at more or less the same time.”

MESSENGER was designed to study Mercury, not comets, “but it is a capable spacecraft with a versatile instrument package,” he adds. “We hope to get some great data.” Onboard spectrometers will analyze the chemical makeup of the two comets while MESSENGER’s cameras snap pictures of atmospheres, jets and tails.

Auroras Underfoot (signup)

Comet ISON is already a media favorite. Astronomers have been tracking it since Sept. 2012 when it was discovered on a trajectory that would take it perilously close to the sun.  On Nov. 28th of 2013, Thanksgiving Day in the USA, Comet ISON will pass through the sun’s atmosphere little more than a million kilometers above the sun’s fiery surface.  If the icy comet survives, it could emerge as a beautiful naked-eye object for observers in the northern hemisphere.  MESSENGER’s glimpse of Comet ISON as it plunges inward could give astronomers the data they need to predict the comet’s fate.

Comet Encke is less well known, but no less interesting.  For one thing, it is the source of the Taurid meteor shower, a slow display of midnight fireballs that occurs every year in early- to mid-November. Comet Encke dips inside the orbit of Mercury every 3.3 years, so it is regularly exposed to solar activity.  In 2007, NASA’s STEREO spacecraft watched as a solar storm ripped off Encke’s tail–which promptly grew back: movie.

“We’ll be catching Comet Encke just days before its closest approach to the sun (0.3 AU),” Vervack  says, “so we get to see it at its most active.”

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MESSENGER’s first images of the approaching comets. Larger image, details

Ironically, the fact that MESSENGER is designed to study a rocky planet could prove advantageous for the icy comets.  MESSENGER’s x-ray spectrometer, in particular, could detect signs of ‘comet dirt’.

“We hope to obtain the first definitive detections of x-ray emissions from silicon, magnesium and aluminum,” he explains. “If you think of a comet as a dirty snowball, these are elements that make up the dirt.  Close to the sun is where we expect the dirt to be vaporized.”

In total, Vervack expects MESSENGER to gather 15 hours’ worth of data on Comet Encke and another 25 hours on Comet ISON.  With that kind of observing time, discoveries are a distinct possibility.

Vervack says the first images will be beamed back and released to the public within days of the flybys.  “There are no guarantees,” he cautions, “but I can’t wait to see the pictures.”

from:    http://science.nasa.gov/science-news/science-at-nasa/2013/15nov_twocomets/

Comet Linear X1 Explodes

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COMET LINEAR X1: The sun isn’t the only thing exploding. Almost 450 million km from Earth, Comet C/2012 X1 (LINEAR) is having its own outburst. On Oct. 20th, amateur astronomers realized that the comet’s brightness had increased 100-fold and its morphology resembled that of exploding Comet 17P/Holmes in 2007. Follow-up images in recent nights seem to show jet-like structures in Comet LINEAR X1’s expanding atmosphere. Amateur astronomer Nick James of Chelmsford, UK, obtained these data on Oct. 26th:

Another set of images taken by James shows the comet’s atmosphere or “coma” expanding over a period of two days. “The coma’s diameter is increasing at a rate of 30 arcseconds per day,” says James. “At a distance of 2.95 AU this corresponds to 65,000 km/day or a little less than 1 km/s.” He made these observations using an 11-inch Celestron telescope.

Located in the constellation Coma Berenices, Comet LINEAR X1 rises in the east about an hour before the sun. The low altitude of the comet in morning twilight is a challenge, but because the comet is fairly bright, magnitude +8.5, it is still a relatively easy target for backyard telescopes equipped with digital cameras. Monitoring is encouraged! Resources: 3D orbit, ephemeris, sky map.

from:    spaceweather.com

What is the Strange LIght in the Western Sky?

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Unknown Glowing Light In Evening Western Sky - Starship? Comet? Nibiru? Hercolubus?
Unknown Glowing UFO In Evening Western Sky – Starship? Comet?  Nibiru? Hercolubus?

Last updated on October 16, 2013 at 12:00 am EDT by in5d Alternative News

 

 

 

by Gregg Prescott, M.S.

For the past week or longer, there has been a strange, glowing UFO in the horizon of the western sky and according to SkEye and Stellarium, there are no stars or planets in that area.

If you are looking at the western sky in the early evening, you will see Arcturus glowing as well as Venus.  You will also see a light to the left of Arcturus that is not defined by the skymap, SkEye.

You will see this bright light in the early evening in the western sky.

Unknown Glowing Light In Evening Western Sky - Starship? Comet? Nibiru? Hercolubus? | In5D.comSkEye is a free app for your cell phone that maps out the sky for you.  With this app, you can see every known star, planet and constellation.

Similar to Venus, this light is not seen very high above the ecliptic plane of earth’s orbit.

While zooming in on it with my Canon 35x Powershot, the light would change from red to green to white.  Even with a tripod, I had difficulty zooming in and focusing in on it but I will continue trying to get empirical video and photos of this anomaly.

My particular sighting came from the Gulf Coast of Florida but this sighting has also been reported from coast to coast in the United States as well as all around the world.

From New York City, “I noticed a star of unusual brightness. It seemed to be flickering from red, to blue to green to white.”

Unknown Glowing Light In Evening Western Sky - Starship? Comet? Nibiru? Hercolubus? | In5D.comFrom Virginia, “Incredible. I live in Virginia Beach and work in Norfolk. I’ve been noticing this object for about a month now, I just shrugged it off as Venus. I tried using Google Sky on my phone but no label came up for it – and I still convinced myself that its Venus and that my phone must just be buggy. I’m weirded out now and still can’t fathom this being a strange planetary object…”

From Massachusetts: “I’m in Massachusetts and I saw it Wednesday evening. The strange thing is, there were no other stars in the sky, none. My husband tried ti convince me that it was Venus, but I don’t think so. It was too big, too bright and like I said, there was not a single other star to be seen.”

From North Carolina: “I live on the foothills of the blue ridge Mts …. near Boone NC and I have been watching this “object” for a year. I remember last year on the way back from Charlotte my son noticed it after I had been watching it for a while. It has gotten allot brighter.”

From England: “Finaly I find soneone else who can see it. I see it also and when I looked in my telescope it made me feel ill. Its weird looks like a cell or germ it flickers red and blue. It changes shape and when I look Unknown Glowing Light In Evening Western Sky - Starship? Comet? Nibiru? Hercolubus? | In5D.comat it I get this creepy feeling like it knows im watching. Im in northeast england and it becomes visible just after sunset.”

From Spain, “we were travelling north on the Alicante-Valencia highway, close to Denia. It was after sunset and we were surprised to see a very bright star (the brightest star one can see in the sky) that pulsated with different colours.”

From Brazil, “First, I thought that it could be Jupiter, and then I tried to see it better using a telescope. I didn’t see the moons of Jupiter that normally appear when you are using the telescope, and I realized that the strange object was emitting light of its own, and not reflecting the light of the sun as a planet does. I enlarged the image several times using the telescope, and I realized that the object, although very bright, was rather small. The next day, using the Stellarium computer program, I realized that there was no object showing in the location that I saw.”

In Japan, a witness saw a ‘mysterious luminary object’ from their window in the western sky above the trees. ‘It was emitting light, shining brightly, changing colours, green, yellow, red and so on. It was moving vertically, up and down, while spinning.’

From New Zealand, “I was walking down the stairs to my car when I saw this really bright star shining. It kept changing colours from red to green in the western sky.”

From Scotland, ” During a recent trip to Italy, at the Pedra e Cupa campsite in Budoni, Sardinia, at 5am on Saturday 4 July a bright star was clearly seen in the western region of the sky and was the only star visible in the sky at this time. Was it the ‘star’?”

From Canada, “I see it to from Ottawa, Canada, here it more active around 20:30 pm, it flickers like crazy and the top part grows white then reduces to red weird star….”

Speculation has inferred that this could possibly be a very large comet or possibly an extraterrestrial mothership.  It may even possibly be Hercolubus or Nibiru.

Carlos Muñoz Ferrada is an world renown astronomer who recently stated that Hercolubus will be making a visit near our planet.

At this point in time, it is unsure of the angle and trajectory of Hercolubus but it is said to have wiped out Atlantis and had caused the “great flood” in many religious texts.

If this light is a starship or mothership, it is of massive proportions for it to be bright enough to be seen with the naked eye.

If you know what this bright light may possibly be, then please comment below. Also, if you are able to take any pictures or videos, then please let me know and I’ll add them to this article.

If you have seen this anomaly, please comment below and tell us the state or country you live in. Thank you!

from:    http://in5d.com/unknown-glowing-ufo-starship-comet-nibiru-hercolubus.html

 

Comet ISON Update

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Potentially Dazzling Comet ISON Should Survive Sun Encounter, Study Suggests

By Mike Wall, Senior Writer   |   October 09, 2013
Comet ISON Enhanced Hubble Image space wallpaper
This stunning space wallpaper is a NASA Hubble Space Telescope image of Comet C/2012 S1 (ISON) when the comet was slightly closer than Jupiter’s orbit at a distance of 386 million miles (621 million km) from the sun.
Credit: NASA/ESA,/J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team

The odds are pretty good that Comet ISON will survive its much-anticipated close solar approach next month, a new study suggests.

As long as ISON is a fairly typical comet — one with “normal” size, density and rotational characteristics — it probably won’t disintegrate during its upcoming flyby, which will bring the icy wanderer within just 730,000 miles (1.2 million kilometers) of the sun’s surface on Nov. 28, researchers report.

That’s good news for skywatchers, for Comet ISON could potentially put on a dazzling show if it manages to weather its solar encounter. And it’s also good news for scientists, who have been planning their most intense observations of the comet for after the flyby (since ISON will be easier to see from Earth after the approach than before). [Comet ISON: 8 Things to Know]

Comet ISON Sky Map
 From now through October, comet ISON tracks through the constellations Gemini, Cancer and Leo as it falls toward the sun. Image released March 29, 2013.
Credit: NASA’s Goddard Space Flight Center/Axel Mellinger

In the new study, Matthew Knight of the Lowell Observatory in Flagstaff, Ariz., and Kevin Walsh of the Southwest Research Institute in San Antonio conducted simulations of Comet ISON’s upcoming solar approach, then put the results in context by looking at how other “sungrazing” comets have performed during their encounters with our star.

The possible outcomes for Comet ISON are total disintegration; initial survival with a breakup coming later, perhaps days or weeks after the Nov. 28 flyby; and full survival for another orbit around the sun. Which one of these will actually occur depends on ISON’s size and density, as well as the nature of its rotation (how fast it’s spinning, and in which direction), researchers said.

Comets less than about 0.12 miles wide (0.2 kilometers) face destruction by the sun’s heat, which can evaporate off all of their ices. But scientists think ISON is big enough to deal with this issue; most estimates place the comet’s core between 0.12 miles and 1.2 miles across (0.2 to 2 km).

Another threat comes from the immense gravitational pull of the sun, which can tear apart comets that are unusually light and fluffy. But as long as ISON is of roughly average density, it should be able to hold together, researchers said

None of this is set in stone, of course, since most of the key characteristics — including Comet ISON’s exact size, density and spin — remain unknown. And it’s notoriously difficult to predict the behavior of comets, especially “dynamically new” ones like ISON making their first trip to the inner solar system from the distant, frigid Oort Cloud.

“Whether or not disruption occurs, the largest remnant must be big enough to survive subsequent mass loss due to evaporation for Comet ISON to remain a viable comet well after perihelion,” Knight said in a statement.

Meanwhile, another new study suggests that Comet ISON might exhibit a burst of activity a week before its close solar encounter.

Researchers used NASA’s Hubble Space Telescope to measure the rotational pole of ISON’s core and determined that only one side of the comet is being heated thus far as it streaks toward the sun.

But that should change on or around Nov. 21, when Comet ISON ducks inside the orbit of Mercury, the solar system’s innermost planet, team members said.

“Since the surface on the dark side of the comet should still retain a large fraction of very volatile materials, the sudden exposure to the strong sunlight when it gets closer to the sun than Mercury could trigger huge outbursts of material,” study leader Jian-Yang Li, of the Planetary Science Institute in Tucson, Ariz., said in a statement.

Both studies were presented today (Oct. 9) at the American Astronomical Society’s Division for Planetary Sciences 45th annual meeting in Denver.

from:    http://www.space.com/23124-comet-ison-sun-encounter-survival.html