ScienceCasts: Some Comets Like It Hot

[ILoveDominikaDetko]

What that piece of ice did survive & will comeback in 600 Years?

So the inner comet had to be made of heavymetal when the outside is rockin with ice.

The Tail is lookin so weird cos the comet did lost its tail already for a sh time (Sun FlareHit)? & THE SUN IS SO HOT WHERE DID THE TAIL GO?, THERE IS NO TAIL AND NEVER WILL BE A TAIL, NEAR SUN IS BURNIN EVERYTHING, exspecially small particles & after that it got a tail again cos its colder? Tail is not H2 after, would be burned away, metal gases?

[camellset]

Sorry, the explaination of this comet and its survival through the solar corona is incorrect. Please reconsider your thoughts.

[Adelastro]

Thanks NASA for showing my photo at 3:53! The video is awesome.

[m0skit0zindahouse]

Damn! A Game Boy @ 0:27!

[888Quetzalcoatl888]

This is total bullshit

[Saparonia]

A million degree corona not melting an icy snowball is a logical impossibility.

[MeganSpeaks]

@Saparonia Not really, in fact I know exactly why. The cold and heat balance out the core.

[astrodotsg]

The photo shown at 4:03 was taken by Jiao Hao. He is a forum member of SINGASTRO, a public amateur astronomy forum in Singapore. This photo and two more stunning wide-views of the comet taken by him in Australia can be found in the astrophotography section of the forum --> singastro [dot] org

[you2tooyou2too]

I wonder how long until they can measure how much orbital (kinetic) energy the comet has lost from its 'collision' with the sun. That could also tell us more about the density curve of the sun or its atmosphere.

[you2tooyou2too]

I cannot easily imagine the solar light generation process being cool, but in a sense, the heat you feel in your skin is extremely local (not even para-terrestrial as someone mentioned). Even the air does not convert the sunlight to heat nearly as much as more energy absorbent materials like our skin, which can then feel the 'heat' directly.

[you2tooyou2too]

A lot of interesting questions, but the tail (perspective acknowledged) requires at least smooth solar wind to form, which might not exist within the solar atmosphere. I can imagine a protective process like the very stable water droplets on a hot skillet. I can imagine the irregular trail (not tail) could be due to decent tumble, and turbulence in the solar atmosphere, as well as plasma-magnetic interaction. CMEs and such are deep magnetic, not superficial mechanical phenomena.

[Saparonia]

@you2tooyou2too A hot skillet isn't very hot and if you put ice on it it will melt immediately with a lot of noise. The water droplets on a hot skillet only last for seconds. This small piece of gritty ice was inside the corona of a star. We are told it is millions of degrees Celsius there and this Has to be wrong. The one factor we should be taking into consideration is that the Sun was extremely quiet and we can LOGICALLY surmise that activity was more relevant than heat.

[Saparonia]

The Sun was unusually quiet and there was no activity when the comet passed spending an hour within the Sun's corona. Ice melts in high temperatures and even a comet 5 times the size of a football field cannot logically stay frozen in temperatures of millions of degrees. The only logical explanation is that the Sun, despite being plasma and giving off radiation of many types, is not hot but is cool. The heat we feel is produced by interaction of our electromagnetic shield and the solar wind.

[Greddier1]

lost its tail? i dont think so. we were viewing it from the front. so the tail is hidden behind the head. more like a fish for example. if it is viewed from side, we can see its tail. if from front, we can only see its head.

[Saparonia]

@Greddier1 Yes I agree, it is perspective.

I also think that the heat we appear to feel from the Sun is also perspective. In fact it is local not solar.

This comet was 200 meters and they seem to be trying to change the measurements of it to fit it with existing beliefs of the Sun being hot.

Plasma and radiation are not necessarily hot but can blast a ball of ice to pieces which is what usually happens.

There were no flares, no coronal holes and no CME's when Lovejoy was within the corona.

[MeganSpeaks]

@Greddier1 It lost its tail. The material in the Tail was melted away thus not exposing the tail if there is no material. The core of the comet though survived due to heat and cold balancing out.

[Saparonia]

@MeganSpeaks Someone on here pointed out that it was travelling towards us and the tail was behind it. NASA have a new baby in the July 2011 comet that disintegrated but if you check it out the Sun was emitting flares and CME's at the time. I am just waiting for the next one when the Sun is quiet, but they will probably have technical faults that prevent them publishing anything that supports the Sun being in fact cool.

[kpheider]

"Using a 40 day (2012-01-06) observation arc": As of 2011-Dec-16 05:00UT, I think Lovejoy has been ejected from the Solar System and will NOT be back. Lovejoy looks like it was at aphelion 136.9AU from the Sun in 1729. Of course a 40 day observation arc is also somewhat lacking for absolute answers hundreds of years into the future/past.

[netman21]

Those claims of loosely compacted dust and ice seem unfounded. EVERY flyby of a comet has shown cratered hard surfaces just like an asteroid. And how can comets form tails of sublimated water vapor out past the orbit of Jupiter where the Sun's light does not provide enough warmth?

[kpheider]

@netman21 Comet are made of volatile ices (water, ammonia, methane, etc.) and non-volatile materials.

[TheWillwillwill]

How do we know this thing was made of ice? If it was ice it would have exploded from the million degree temp from the suns corona. also if you place water in a stream of charged particles I think electrolysis of water would result in hydrogen and oxygen which would ignite.

[CPMSTV]

Amazing clips of the comet and the sun!

[RustyRazor2010]

Lost it's tail? I would think that it was still present at the time in a non-visible form (gas) because of sublimation.

[bedzinskiwr]

wrbedzinski:very good of performancy in galaxy!

[cruxader27]

why is that comets tail points away from the sun?

[rjestin]

@cruxader27 The sun continually produces a stream of charged particles in all direction away from the sun. It called the Solar wind and it travels outward from the sun faster than the comet is moving. It's kind of like a windsock effect, except the wind is charged particles from the sun, and the sock is the fragment of comet that break and melt off in the heat of the sun.

[cheenaproductions]

Perhaps it survives just as Love and Joy survive. Infinitely

[TheTrieye]

kool

[comvitor]

No mention in this vid about:

1: What happened with this comet at Dec 21-22, as recorded by SECCHI B - HI1? Please see dutchsince video (search for, I couldn't post the link here...)

2: Why suddenly Lovejoy disappear from the photographer's sight after several amazing photos taken day by day from south hemisphere?

[TheChannelZeroNews]

If the comet is a rock of ice and the sun is extremely hot, how does a comet even come a few million miles close to the sun?

[accd1d]

cool, was it made of mostly tetrahedrally bonded carbon atoms ? that would make sense. Cheers, -a

[LsBaba]

One of my fav SciAtNASA vids. It's nice to know we don't know so much :) Life is interesting.

[mundoovni]

Fasinating!! Thanks for the information! :D

[antony492]

The Sun is shaking it's fist at it "I'll get you in 6000 years time"

[docatomics]

...and again we didn't see it coming

~good thing is wasn't Earth directed if it had broken up

=seem-to-be this need$ more $urvival $pending $pending

[Rocflanagan]

I wonder how they estimated that it won't be back for six hundred years...

[Zorgonia]

@Rocflanagan simple Newtonian physics, the same way rockets orbits are calculated and the same way that Halley predicted -correctly- that his namesake comet would return every 76 years.

I wonder, are you very young or home schooled?

[Warlockofhell]

Good stuff, see ya in 600 years!

[TheAtheistSocialist]

Science Rules !

[TheAtheistSocialist]

I love how absolutely godless this video is.

[smooth73074]

Fascinating!

[RosePetalsFalling]

I wish I could have seen this!

[jasleil]

I hate you Comet Lovejoy, you didn't visit the northen hemispher!!

600 years for the next visit, oh man. I'll never get to see it.