Asteroids

[viscount aero]

Where's the gravity effect. Pieces floating off! There should be a accretion to all asteroids...

LOL!!!

[viscount aero]

There was another story a while ago similar to this one whereby an asteroid "suddenly" began flaring up and producing a "comet-like tail." And that it "baffled scientists." Yet it was never mentioned that comets may actually be asteroids and vice versa. Or that what they were witnessing was the "birth" of comet, ie, comets must come from somewhere and begin exhibiting their characteristic luminous tails at some point. But it never occurs to them they are seeing this phenomena caught in the act. They must also think, in absolute terms, that all comets must have highly eccentric and unstable orbits. So they must have really been dumbfounded when they recently discovered an asteroid with its own ring system.

From:
http://arxiv.org/abs/1403.1237

"Disintegrating Asteroid P/2013 R3
David Jewitt, Jessica Agarwal, Jing Li, Harold Weaver, Max Mutchler, Stephen Larson
(Submitted on 5 Mar 2014)

Splitting of the nuclei of comets into multiple components has been frequently observed but, to date, no main-belt asteroid has been observed to break-up. Using the Hubble Space Telescope, we find that main-belt asteroid P/2013 R3 consists of 10 or more distinct components, the largest up to 200 m in radius (assumed geometric albedo of 0.05) each of which produces a coma and comet-like dust tail. A diffuse debris cloud with total mass roughly 2x10^8 kg further envelopes the entire system. The velocity dispersion among the components is about V = 0.2 to 0.5 m/s, is comparable to the gravitational escape speeds of the largest members, while their extrapolated plane-of-sky motions suggest break-up between February and September 2013. The broadband optical colors are those of a C-type asteroid. We find no spectral evidence for gaseous emission, placing model-dependent upper limits to the water production rate near 1 kg/s. Breakup may be due to a rotationally induced structural failure of the precursor body."

"ld Weaver, Max Mutchler, Stephen Larson
(Submitted on 5 Mar 2014)

To this: "Splitting of the nuclei of comets into multiple components has been frequently observed but, to date, no main-belt asteroid has been observed to break-up"---that doesn't mean that asteroids do not break up and with probable frequency. Comets are often attractive to telescopes because of their inherent beauty and luminosity. Besides being specks of nothingness in the cosmic ocean, asteroids are just mere rocks. But are they?

"Splitting of the nuclei of comets into multiple components has been frequently observed but, to date, no main-belt asteroid has been observed to break-up. Using the Hubble Space Telescope, we find that main-belt asteroid P/2013 R3 consists of 10 or more distinct components, the largest up to 200 m in radius (assumed geometric albedo of 0.05) each of which produces a coma and comet-like dust tail"---I haven't observed my own stomach nor anyone else's but I know stomachs exist and with great frequency. There are probably much more of these asteroids breaking up like this. And again they don't at all draw any line from asteroids to comets even though they must use the terms "coma" and "comet-like dust tail." Regardless it just cannot be a comet nor even a type of comet They pay no heed to Darwin whatsoever, which is baffling coming from scientists, in that they seem to disallow for "species" of comets or anything else in the cosmos. Something must "only be" a planet. Something must "only be" an asteroid. There is no such thing as a variation upon a theme in astronomy for them

"The broadband optical colors are those of a C-type asteroid. We find no spectral evidence for gaseous emission, placing model-dependent upper limits to the water production rate near 1 kg/s. ---I must be missing something. Where do they get "water production rate" from?

"Breakup may be due to a rotationally induced structural failure of the precursor body."---That's like saying "the car encountered structural failure upon falling from the 67 story parking garage as it hit the ground," ie, it doesn't really explain how the car got into a situation where it would fall from 67 stories in the first place. Saying "rotationally induced structural failure" doesn't really say anything. It's also like saying "Clearly his face was contorting in pain because he had an internal bodily anomaly. Let's give him some pills for the internal bodily anomaly"--which offers no actual remedy as to what the pain is caused by, or why it is there, where it is coming from.

[Sparky]

"Breakup may be due to a rotationally induced structural failure of the precursor body."--

If a little bit of rotation can tear it apart, what are they thinking to arrive at that?
The asteroid must be structurally weak, and some force caused the rotation to exceed that structural limit. If it is structurally weak,,, such as a pile of gravel, then how has it been held together til now? And if it is cohesive enough to hold together, what force would set it to spinning without breaking it. This explanation produces more questions than it answers.

[viscount aero]

"Breakup may be due to a rotationally induced structural failure of the precursor body."--

If a little bit of rotation can tear it apart, what are they thinking to arrive at that?
The asteroid must be structurally weak, and some force caused the rotation to exceed that structural limit. If it is structurally weak,,, such as a pile of gravel, then how has it been held together til now? And if it is cohesive enough to hold together, what force would set it to spinning without breaking it. This explanation produces more questions than it answers.

Yes that's exactly what I'm saying; you've pointed out another way of saying it. The statement of theirs says virtually nothing in actuality. It offers no explanation or cause. It's like they said "With the man observed on fire he was clearly burning." And they stop with that. Nothing else is offered for discussion.

[Trouserman]

"Breakup may be due to a rotationally induced structural failure of the precursor body."--

If a little bit of rotation can tear it apart, what are they thinking to arrive at that?
The asteroid must be structurally weak, and some force caused the rotation to exceed that structural limit. If it is structurally weak,,, such as a pile of gravel, then how has it been held together til now? And if it is cohesive enough to hold together, what force would set it to spinning without breaking it. This explanation produces more questions than it answers.

They do provide a possible explanation: YORP torque, an effect of irregular thermal radiation. This could plausibly spin up an asteroid over the course of millions of years, however weak the forces holding it together.

[Steve Smith]

It looks like only one dashcam caught the event. Even though there are several postings (some with misleading intro stills) it's always the same car at the same place at the same time.

https://www.youtube.com/results?search_ ... eor&page=1

[viscount aero]

They do provide a possible explanation: YORP torque, an effect of irregular thermal radiation. This could plausibly spin up an asteroid over the course of millions of years, however weak the forces holding it together.

I hadn't seen the below article until today, but the YORP idea is highly specious of an explanation when reading the main points of the press release below. On the surface, the idea does sound plausible until you follow their train of logic as the report unfolds:

from: http://www.csmonitor.com/Science/2014/0 ... g-asteroid

"Back in 2010, astronomers discovered an asteroid that was breaking apart due to a head-on collision with another asteroid. But now they have seen an asteroid break apart – with no recent collision required.

They assume almost everything that fragments or blows apart must be collision-based.

Asteroid P/2013 R3 appears to be crumbling apart in space, and astronomers using the Hubble Space Telescope recently saw the asteroid breaking into as many as 10 smaller pieces. The best explanation for the break-up is the Yarkovsky–O’Keefe–Radzievskii–Paddack (YORP) effect, a subtle effect from sunlight that can change the asteroid’s rotation rate and basically cause a rubbly-type asteroid to spin apart.

“This is a really bizarre thing to observe — we’ve never seen anything like it before,” said co-author Jessica Agarwal of the Max Planck Institute for Solar System Research, Germany. “The break-up could have many different causes, but the Hubble observations are detailed enough that we can actually pinpoint the process responsible.”

Astronomers first noticed this asteroid on September 15, 2013 and it appeared as a weird, fuzzy-looking object, as seen by the Catalina and Pan-STARRS sky-survey telescopes. A follow-up observation on Oct. 1 with the W.M. Keck telescope on Hawaii’s Mauna Kea revealed three co-moving bodies embedded in a dusty envelope that is nearly the diameter of Earth.

Then on October 29, 2013, astronomers used the Hubble Space Telescope to observe the object and saw there were actually 10 embedded objects, each with comet-like dust tails. The four largest rocky fragments are up to 200 meters/yards in radius, about twice the length of a football field.

The Hubble data showed that the fragments are drifting away from each other at a leisurely pace of 1.6 km/hr (one mile per hour), which would be slower than a strolling human.

Seeing this rock fall apart before our eyes is pretty amazing,” said David Jewitt, from UCLA’s Department of Physics and Astronomy, who led the investigation.

The slowness of the speed at which the pieces are coming apart makes it unlikely that the asteroid is disintegrating because of a collision. That would be instantaneous and violent, with the pieces traveling away from each other at much higher speeds.

Jewitt also said the asteroid is not coming unglued due to the pressure of interior ices warming and vaporizing, like comets do as they approach the Sun.

They actually continue to believe this about comets despite probes that have disproven the existence of icy coma.

The asteroid is too cold for ices to significantly sublimate, and it has presumably maintained its nearly 480 million-km (300 million–mile) distance from the Sun for much of its life.

At least they say 'presumably' as they don't actually know what the asteroid has done for much of its life. But they presume there are "ices" on it anyway. And they forget that some comets have begun "sublimating their ices" much farther out than 300 million miles.

Jewitt described the YORP torque effect as like grapes on a stem being gently pulled apart due to centrifugal force of an unusually shaped asteroid as it speeds up in its spin. This effect occurs when light from the Sun is absorbed by a body and then re-emitted as heat. When the shape of the emitting body is not perfectly regular, more heat is emitted from some regions than others. This creates a small imbalance that causes a small but constant torque on the body, which changes its spin rate. This effect has been discussed by scientists for several years but, so far, never reliably observed.


Although YORP torque is not entirely unbelievable, it feels too "reaching" of an idea as it does not take into account 1. the trillions of oblong asteroids that are not breaking apart, phenomena that should be commonly seen nearly everywhere were this truly the cause 2. symmetrical objects that break apart 3. laboratory YORP torque statistics specific to rocky bodies in zero g. It would have been more elegant of an explanation to just say "the rock simply fell apart as it weakened over time"--that would have been more believable than invoking a quasi-factual YORP torque theory for this body

For the break-up to happen, P/2013 R3 must have a weak, fractured interior, probably as the result of previous but ancient collisions with other asteroids. Most small asteroids, in fact, are thought to have been severely damaged in this way, giving them a “rubble pile” internal structure. P/2013 R3 itself is probably the product of collisional shattering of a bigger body some time in the last billion years.

They're assuming that everything must be result of collisions that then result in alleged rubble piles. That would mean that 1. There is a collision, that there are millions and trillions of collisions between tiny bodies in space. 2. The fragmented material then reconvenes and recombines into a "pile." They leave out explaining the unspoken step by which the rubble, once collided, then recombines into a pile. That would imply that the gravity acts like a magnet that re-attracts the smashed material back together. That or a significant number of asteroids are all "weak inside" due to "collisions" with other tiny bodies. Does that really occur in space?

With Hubble’s recent discovery of an a different active asteroid spouting six tails (P/2013 P5), astronomers are seeing more circumstantial evidence that the pressure of sunlight may be the primary force that disintegrates small asteroids (less than a mile across) in the Solar System.

That borders on being a ridiculous idea. Sunlight pressure may be the PRIMARY force that disintegrates small asteroids? They must be in bed with their theory of the Pioneer anomaly along those lines of thinking...

The asteroid’s remnant debris, estimated at weighing in at 200,000 tons, in the future will provide a rich source of meteoroids, Jewitt said. Most will eventually plunge into the sun, but a small fraction of the debris may one day enter the Earth’s atmosphere to blaze across the sky as meteors, he said."

That is probably true.

The discovery is published online March 6 in Astrophysical Journal Letters. A preprint of the paper can be found here: http://arxiv.org/abs/1403.1237

[Sparky]

Most will eventually plunge into the sun,

Have you checked on the asteroid/debris trajectory? Could the sun boost this back toward it's origin? Acquiring a retuning obit.!!!. Then we would have this debris cloud sweeping through the planet's orbits for millennia !!!!

[Jatslo]

...a collision with anti-matter would have certainly released enough energy to break apart and asteroid. The balance between certain matter and antimatter particles tipped toward normal matter by just 1 percent during the particle-smashing run at the 4-mile Tevatron collider at the Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Ill. It's highly unlikely that the 1 percent came about due to chance, according to statistical analysis, researchers said.

When matter and antimatter meet, they self-destruct - "annihilate"; KAPOW!!! So consider that the universe is made of primarily or mostly hydrogen. The H bomb uses uranium or plutonium to create a massive explosion (using fission) that creates enough heat to force hydrogen to fuse to other hydrogen, forming helium, which gives an even bigger explosion. (By hydrogen, I mean hyrdogen or one of its isoptopes, deuterium or tritium).

Annihilation, oh my!

[viscount aero]

...a collision with anti-matter would have certainly released enough energy to break apart and asteroid. The balance between certain matter and antimatter particles tipped toward normal matter by just 1 percent during the particle-smashing run at the 4-mile Tevatron collider at the Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Ill. It's highly unlikely that the 1 percent came about due to chance, according to statistical analysis, researchers said.

When matter and antimatter meet, they self-destruct - "annihilate"; KAPOW!!! So consider that the universe is made of primarily or mostly hydrogen. The H bomb uses uranium or plutonium to create a massive explosion (using fission) that creates enough heat to force hydrogen to fuse to other hydrogen, forming helium, which gives an even bigger explosion. (By hydrogen, I mean hyrdogen or one of its isoptopes, deuterium or tritium).

Annihilation, oh my!

Greetings, Jatslo. Welcome to thunderbolts. Interesting first post.

[Jatslo]

I thought I would honor the creators of this website with some thunderbolts:

"Scientists using NASA's Fermi Gamma-ray Space Telescope have detected beams of antimatter produced above thunderstorms on Earth, a phenomenon never seen before."

http://www.nasa.gov/mission_pages/GLAST ... torms.html

"Fermi is designed to monitor gamma rays, the highest energy form of light. When antimatter striking Fermi collides with a particle of normal matter, both particles immediately are annihilated and transformed into gamma rays. The GBM has detected gamma rays with energies of 511,000 electron volts, a signal indicating an electron has met its antimatter counterpart, a positron."

If the the universe was created in some colossal explosion, then there should be almost a 50:50 ratio; antimatter to matter ratio. That's a big IF. Do the math folks: How much antimatter would it take to break an asteroid into as many pieces as we see at those proportions?

This is a test!

[Jatslo]

If I were going to develop the ultimate weapon against impacters, such as, Comets and Asteroids, I'd make a antimatter weapon, and I'd test it on an asteroid. I'd want to disintegrate it before it hit Earth, for example.

"The United States Air Force, however, has been interested in military uses — including destructive applications — of antimatter since the Cold War, when it began funding antimatter-related physics research. The primary theoretical advantage of such a weapon is that antimatter and matter collisions convert a greater fraction of the weapon's mass into explosive energy when compared to a fusion reaction, which is only on the order of 0.4%."

http://en.wikipedia.org/wiki/Antimatter_weapon

Now, I'm sure you have all heard of "Tesla Lightening Weapons?"

[Trouserman]

Although YORP torque is not entirely unbelievable, it feels too "reaching" of an idea as it does not take into account 1. the trillions of oblong asteroids that are not breaking apart, phenomena that should be commonly seen nearly everywhere were this truly the cause 2. symmetrical objects that break apart 3. laboratory YORP torque statistics specific to rocky bodies in zero g. It would have been more elegant of an explanation to just say "the rock simply fell apart as it weakened over time"--that would have been more believable than invoking a quasi-factual YORP torque theory for this body

I understand you doubt this explanation. I'm not married to it, myself. My objection is to characterizing the paper as offering no explanation for an increasing spin rate. 1. As this process is extremely slow, and will only cause breakup of structurally weak objects, it's not clear to me that it should be commonly seen nearly everywhere. 2. The paper does not propose that this is the explanation for all break-ups, but may be the explanation in this particular case. I would be interested in reading about examples of symmetrical objects breaking up in a similar fashion, if you have them. 3. I'm not familiar with laboratory results on YORP. Theoretically, it is a direct consequence of blackbody radiation, momentum carried by light, and conservation of momentum, applied to an irregular body with nonuniform heating. If you consider YORP quasi-factual, I wonder which of these you doubt. (Or perhaps you don't trust the mathematics or think there is some undiscovered counterbalancing effect.)

[viscount aero]

Although YORP torque is not entirely unbelievable, it feels too "reaching" of an idea as it does not take into account ...

I understand you doubt this explanation. I'm not married to it, myself. My objection is to characterizing the paper as offering no explanation for an increasing spin rate. 1. As this process is extremely slow, and will only cause breakup of structurally weak objects, it's not clear to me that it should be commonly seen nearly everywhere. 2. The paper does not propose that this is the explanation for all break-ups, but may be the explanation in this particular case. I would be interested in reading about examples of symmetrical objects breaking up in a similar fashion, if you have them. 3. I'm not familiar with laboratory results on YORP. Theoretically, it is a direct consequence of blackbody radiation, momentum carried by light, and conservation of momentum, applied to an irregular body with nonuniform heating. If you consider YORP quasi-factual, I wonder which of these you doubt. (Or perhaps you don't trust the mathematics or think there is some undiscovered counterbalancing effect.)

I don't doubt the mathematics involved in YORP. For example, I don't doubt the mathematics specifically describing the expansion metric. I simply doubt in the belief that there is cosmological expansion as described by the metric. With YORP, I think the people who invented it are quite intelligent and the math is sound. But is it describing something that actually happens?

To your point 1: The article implies that rubble piles and collisions that led to the breakup are common occurrences:

"For the break-up to happen, P/2013 R3 must have a weak, fractured interior, probably as the result of previous but ancient collisions with other asteroids. Most small asteroids, in fact, are thought to have been severely damaged in this way, giving them a “rubble pile” internal structure. P/2013 R3 itself is probably the product of collisional shattering of a bigger body some time in the last billion years."


So where are all of the breakups due to YORP? There should be trillions of breakups as the Sun shines 24/7 in space upon all of the shattered debris floating around.

To your point 2: see above

Point 3: To reiterate, I do not entirely disbelieve the occurrence of a YORP effect but I find it very reaching of an idea in this case. I doubt severely that the rocky debris that underwent collisions is all static and non rotational. Certainly, some of the rocks are probably not spinning, but I'd bet most are tumbling through space as they travel. So they're already on the threshold of flying apart on their own anyway (if you must adhere to purely mechanical causes for breakup). If anything, the rock simply flew apart. There is no need for anything exotic to explain it (However it is the cometary-like structures observed which takes this into another area--one which I'm not totally answering to here).

To then invoke a mysterious and far-fetched idea that UV radiation tacitly exhaled on one of the rocks, and then broke it apart, is not a very believable idea particularly when/if there are no actual accounts of this happening via experiment (which places YORP into the realm of theoretical physics such as worm holes and branes). And particularly when the observation of such breakups is apparently so rare when UV, space rocks, and alleged rubble pile-inducing collisions are not rare. See my reply to point 1 again.

Sure, it could happen. I do leave that open for consideration. But in light of the other circumstances around smashed debris I highly doubt the YORP effect is actually happening here. If I am in error about my current understanding of YORP and its testability then I will accept this and stand corrected. It's only a chat forum

[Sparky]

An asteroid comes apart, slowly or in an explosion, by way of electrical disassociation of it's bonds. If it presents a tail it is called a comet. A comet is an asteroid with electrical activity on it's surface, expelling ions, and it's chemical bonds being disassociated by electrical currents, which produces explosions.

YORP