Mars' moon Phobos is slowly falling apart

Mars’ Moon Phobos is Slowly Falling Apart
New modeling indicates that the grooves on Mars’ moon Phobos could be produced by tidal forces – the mutual gravitational pull of the planet and the moon. Initially, scientists had thought the grooves were created by the massive impact that made Stickney crater (lower right). Credit: NASA/JPL-Caltech/University of Arizona

The long, shallow grooves lining the surface of Phobos are likely early signs of the structural failure that will ultimately destroy this moon of Mars.

Orbiting a mere 3,700 miles (6,000 kilometers) above the surface of Mars, Phobos is closer to its planet than any other in the solar system. Mars' gravity is drawing in Phobos, the larger of its two moons, by about 6.6 feet (2 meters) every hundred years. Scientists expect the moon to be pulled apart in 30 to 50 million years.

"We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves," said Terry Hurford of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

The findings by Hurford and his colleagues are being presented Nov. 10, 2015, at the annual Meeting of the Division of Planetary Sciences of the American Astronomical Society at National Harbor, Maryland.

Phobos' grooves were long thought to be fractures caused by the impact that formed Stickney crater. That collision was so powerful, it came close to shattering Phobos. However, scientists eventually determined that the grooves don't radiate outward from the crater itself but from a focal point nearby.

More recently, researchers have proposed that the grooves may instead be produced by many smaller impacts of material ejected from Mars. But new modeling by Hurford and colleagues supports the view that the grooves are more like "stretch marks" that occur when Phobos gets deformed by tidal forces.

The gravitational pull between Mars and Phobos produces these tidal forces. Earth and our moon pull on each other in the same way, producing tides in the oceans and making both planet and moon slightly egg-shaped rather than perfectly round.

The same explanation was proposed for the grooves decades ago, after the Viking spacecraft sent images of Phobos to Earth. At the time, however, Phobos was thought to be more-or-less solid all the way through. When the tidal forces were calculated, the stresses were too weak to fracture a solid moon of that size.

The recent thinking, however, is that the interior of Phobos could be a rubble pile, barely holding together, surrounded by a layer of powdery regolith about 330 feet (100 meters) thick.

"The funny thing about the result is that it shows Phobos has a kind of mildly cohesive outer fabric," said Erik Asphaug of the School of Earth and Space Exploration at Arizona State University in Tempe and a co-investigator on the study. "This makes sense when you think about powdery materials in microgravity, but it's quite non-intuitive."

An interior like this can distort easily because it has very little strength and forces the outer layer to readjust. The researchers think the outer layer of Phobos behaves elastically and builds stress, but it's weak enough that these stresses can cause it to fail.

All of this means the tidal forces acting on Phobos can produce more than enough stress to fracture the surface. Stress fractures predicted by this model line up very well with the grooves seen in images of Phobos. This explanation also fits with the observation that some grooves are younger than others, which would be the case if the process that creates them is ongoing.

The same fate may await Neptune's moon Triton, which is also slowly falling inward and has a similarly fractured surface. The work also has implications for extrasolar planets, according to researchers.

"We can't image those distant planets to see what's going on, but this work can help us understand those systems, because any kind of planet falling into its host star could get torn apart in the same way," said Hurford.


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Nov 10, 2015
As usual, the explanation relies on something that is out of sight and is not falsifiable. This is the MO of the ad hoc standard theory, ignore reality and blame it on something "dark", out of reach, or "unmeasurable".

Nov 10, 2015
As usual, the explanation relies on something that is out of sight and is not falsifiable. This is the MO of the ad hoc standard theory, ignore reality and blame it on something "dark", out of reach, or "unmeasurable".
@cd
this is what is called a "False Claim"
http://www.auburn...ion.html

the above is an article, and it is based upon a hypothesis (big science term)
there are testable parameters, including (but not limited to) observation

if "Phobos has already started to fail, and the first sign of this failure is the production of these grooves" (from above) then there is a method for a testable prediction, and thus falsification

this differs from your eu claims in that your eu has no predictability
its attempts to date have been a resounding failure
-including: Moon craters, Shoemaker-Levy, Grand Canyon, or Cassini ( http://phys.org/n...oon.html )

Nov 10, 2015
The Electric Universe is repeatedly lambasted for making inferences based upon simple observation, without any actual data beyond the observation.

Yet, is not that PRECISELY what these theorists are doing here? There's not a single piece of data offered beyond the observation of the grooves for why this long story is advocated.

This is sloppy work, and regardless of one's ideology, it should be labeled by all as speculative.

Nov 10, 2015
Yet, is not that PRECISELY
@plasma
short answer: NO

long answer:
1- re-read the above post to cd

2- re read this: https://en.wikipe...c_method

3- the scientific method builds upon past success and validated evidence - the eu has yet to provide that

4- predictability is a good thing

5- failures can also teach us

6- WRT your "looks like a duck" argument above; wolves "look like" dogs to most people, but they're not, and treating them like a dog could get you into a world of sh*t, especially with an Alpha

7- there are means of testing a lot of the hypothesis that eu claims, and the evidence doesn't support the claims (see above list in cd post)

most importantly:
if it were a matter of belief (with eu style observations), we would still believe the earth was flat, that the Pope is ordained from god, that the bible is infallible, that religion is peaceful, and that you can't fly in something heavier than air

Nov 11, 2015
Very interesting. How willl this event in 30-50 million years from now effect the earth and whoever or whatever is still living on earth at the time it occurs? How will it effect mars and any colonies or settlements on mars?

Nov 11, 2015
Re: "long answer ..."

What is the data? There is none. You've completely failed to explain how this is different than pointing to something like an hourglass morphology in space, and likening it to a glow discharge from the plasma laboratory. This press release does the exact same thing.

Nov 11, 2015
So how do you make parallel grooves on Phobos? You can stretch it as the authors mentioned (maybe) or you can hit Phobos with a large enough off-center impact at Stickney Crater to set the entire moon spinning. The secondary impactors (rocks) blown out from Stickney crater will start out in a radial pattern and transition over to a more parallel path pattern, which is what we see. Gravitational interactions with Mars will eventually reestablish the tidal lock, leaving unaware visitors with a mystery, now solved.

If this is right, the fun part is to imagine what this looked like with enormous rocks gouging grooves into the surface as the entire moon spun rapidly.

Nov 11, 2015
Re: "So how do you make parallel grooves on Phobos? You can stretch it as the authors mentioned (maybe) or you can hit Phobos with a large enough off-center impact at Stickney Crater to set the entire moon spinning."

This would be a comprehensive analysis if you assume that at some point between a small iron marble and a body the size of Phobos, objects stop acting as a reservoir for charged particles.

Look carefully at Phobos: What you see are rilles (gouges) which suddenly switch to chains of craters, and vice-versa. Note that we see identical features on Mars ...

http://sen.com/th...eac9.jpg

But, nobody is arguing that Mars is cracking. And neither is anybody arguing that there are collapsing lava tubes on Phobos. The analysis is different for the same observed feature on different bodies.

This raises the possibility of transient electrical events which switch between continuous and sporadic discharges.

Nov 11, 2015
we see identical features on Mars
@plasma
for starters: a long line with secondary linear impact craters beside it is not the same thing as the striated image of Phobos above

two: we already know that Mars had a different atmosphere in the past as well as currently (and historically) has (had) water

generating a hypothesis (as noted and ignored by you) means generating a method to test said hypothesis, which is easy WRT Martian groove you links, but harder WRT Phobos (but not impossible)

this is like the eu ignoring things from Shoemaker-Levy9, Moon craters (or things like this: http://phys.org/n...cke.html ) which are KNOWN methods of impact which can be replicated and tested for the sake of a belief that not only isn't observed, but would be catastrophic if ever observed, considering the energy and more involved


Nov 11, 2015
@plasma cont'd
WRT this
What is the data? blah blah the exact same thing
the press release only explains that they're looking into a hypothesis, not that anything is definitive

then there is the wanting manifested in your observation and seeking information or correlation where there is none to be seen
like this
Look carefully at Phobos: What you see are rilles (gouges) which suddenly switch to chains of craters, and vice-versa. Note that we see identical features on Mars
not only are the not the same, but they're not even close to being similar

this is equivalent to calling a Hummingbird a Raptor barbecue both have wings
lastly
This raises the possibility of transient electrical events...discharges
and yet you still cant demonstrate the events or even the equivalent observed charge/discharge that would cause the damage seen to said objects (which would be considerable)

this IS testable as there would be evidence left behind of a discharge

Nov 12, 2015
Re: "for starters: a long line with secondary linear impact craters beside it is not the same thing as the striated image of Phobos above"

It is the same insofar as we see crater chains switching to rilles/gouges, and vice-versa. Insisting that the craters result from impacts only demonstrates that you are subject to the textbook explanation. This is testament to your own inability to hold the idea as an object such that you can question it. Authentic thinking like a scientist occurs two levels above this socialized mindset. There's no critical aspect to this.

Re: "two: we already know that Mars had a different atmosphere in the past as well as currently (and historically) has (had) water"

If the rilles on Mars are not due to fluids, then that analysis is subject to change. Either way, there is no explanation of Valles Marineris in fluids. So, different explanations are required to explain similar features which differ only in size.

Nov 13, 2015
Insisting that the craters result from impacts only demonstrates that you are subject to the textbook explanation
@plasma
Ah, yes. python logic a combination of "if you can't be there to do X, then you can't say..." mixed with "So, if she weighs as much as a duck..." https://www.youtu...l5ntikaU

i didn't say there was only one possible explanation...

so lets look at this with a logical, scientific mind:

lets assume that there was an event that was 4 times the Carrington event, which we know was quite powerful and we also know is probable... taking said event and then modelling how it would affect Mars (for said crater chain pic) it doesn't provide enough power to cause the damage that is visible in the picture
But that's not all... even if a "plasma event" were to be the cause, it would cause noticeable effects as well as traceable effects that we could measure from our space satellites

2Bcont'd

Nov 13, 2015
@plasma cont'd
and that is assuming that the atmosphere is the same now as it was historically...
but wait, there is more...

if we calculate the probability of this being the cause, it actually comes out very low...whereas if we take the probability of said impacts being due to physical impact of debris, rock, iron, meteorites, meteors, Ice of Comets (any one if them individually), then the odds of the impact being done by said individual mentioned item increase exponentially...
one reason is that we KNOW that there are objects in the paths of the planets that can cause it (we track some, we watch some, and we cross paths with some, like this: http://phys.org/n...cke.html )

so it is not about a wild half-*ssed guess with no information... we actually DO observe these type impacts happening regularly in our own solar system (Shoemaker-Levy9 is one example... broke apart and formed a chain of impacts)

2Bcont'd

Nov 13, 2015
@plasma con't
now lets discuss this
Authentic thinking like a scientist occurs two levels above this socialized mindset. There's no critical aspect to this
which is more logical and critical and the "authentic thinking like a scientist":
- assuming everything is plasma based and therefore (a witch! oops) that vague similarities in pictures that have almost nothing in common must be relevant ( https://en.wikipe...pophenia )

- assuming the most logical cause based upon knowledge, observation and historical data until there is more information that can validate or refute the point

The first is what you and your eu crew do... it is technically called Apophenia
The latter is what the scientific method does https://en.wikipe...cess.svg


Nov 13, 2015
@plasma cont'd
Either way, there is no explanation of Valles Marineris in fluids
this is called an ASSumption
you can't state that there are no or never has been fluid there, especially considering the facts...
http://www.nasa.g...731.html

so this would bring us back to looking at your historical backing of subjects that are not even supported by evidence... one thing makes a huge impact: why you continually attempt to see patterns that are not necessarily there
http://medicalxpr...rns.html

The findings of the study add to a large body of research that suggests that cognitive distortions (or people's warped thinking), play an important role in pathological gambling. It provides further evidence for the assumption that gamblers are particularly prone to perceiving illusory patterns and are more impulsive than others
sounds like the eu in general

Nov 16, 2015
Captain Stumpy

4.4 /5 (13) Nov 10, 2015

As usual, the explanation relies on something that is out of sight and is not falsifiable. This is the MO of the ad hoc standard theory, ignore reality and blame it on something "dark", out of reach, or "unmeasurable".

@cd
this is what is called a "False Claim"


cantthink can't open his mouth without committing a logical falacy. It's part of what makes the religious and conspiracy nutters what they are. But I think you miss the deeper point. They don't care. They're logic deniers. See no use for it. Add to that an inability to appreciate scale and ego identity driven belief systems, sprinkle with a dash of sadism, and you have the garden variety internet troll. For them, if you can imagine it, then it can be true. If you can really imagine it, it really must be true. Problem is, there's often no possible path from there to here. They tend to miss that little detail.

Nov 16, 2015
In tangentially related news, if Phobos whacks Mars it won't be the first Martian satellite to do so.

There are many lines of evidence that the rotation axis of Mars has moved relative to its body (1 2 3). The five or six largest (recognized) impact basins are located on a single great circle. All impact basins centers are located within a maximum latitude of lambda max = 8 degrees.

It is possible that a projectile approaching Mars at a high inclination impacts near the equator. But it is unlikely that five or six projectiles on a highly inclined orbit all impact on the same great circle.

1) Melosh H.J. (1908) Icarus, 73
2) Murray, B.C., and M.C. Malin (1973) Science, 197, 997-1000
3) Schultz, P.H. and A.B. Lutz-Garihan (1982) JGR, 87, A84-A96.

Lunar and Planetary Science XXXVI (2005)
GIANT IMPACT BASINS TRACE THE ANCIENT EQUATOR OF MARS
Jafar Arkani-Hamed (Earth and Planetary Sciences, McGill University, Canada, jafar@eps.mcgill.ca)

Nov 16, 2015
link to above paper -- www.lpi.usra.edu/...2177.pdf

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