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Phobos, the Martian moon, quickly approaches to the surface of the planet due to tidal effect (because Phobos's orbital period is shorter than a Martian day). Only a few hundred million years ago Phobos had to housed almost in a stationary orbit. The probability of formation of Phobos in accuracy in a stationary orbit is negligible. Therefore we must explain how Phobos could be in this orbit.
The author offers the following explanation. After its formation the system of Martian moons consisted of three bodies, like modern Plutonian system. In addition to the tiny moons Phobos and Deimos Mars had another large moon (moon X). Phobos was in orbital resonance with the moon X, and this resonant system was stable and self correcting. Phobos was, as it is now, located below the stationary (areostationary) orbit. The moon X was located above it and tidal influence of Mars pushed the moon X away from the Martian surface. In an effort to keep the orbital resonance, resonant influence of the moon X pulled Phobos up too, in spite of the tidal effect of Mars.
When Phobos had reached stationary orbit, new factor had appeared. This factor was an asymmetry of the Martian surface. Because Phobos's orbital period became equal to Martian day, Phobos located stationary above the surface on Mars, herewith some mountain area was behind him. The force of gravity of huge stone rocks permanently pulling Phobos ago, preventing resonance effect of the moon X. As a result, the moon X continued to rise, and Phobos had stopped at a stationary orbit. Orbital resonance was be broken. From this point Phobos was lowered under the influence of tidal friction of Mars.
The moon X escaped from Mars because of tidal effect. Or it was broken accidentally flown asteroid. Perhaps some meteorites are fragments of the moon X.

Richard C Hoagland believes that Phobos is a spaceship . . .

Hi Krupin,

So, you admonish me to hurry up with my Phobos rendering? Before the mars moon completely disappears...?

Seriously; is this scientifically veryfied? I always thought Phobos (and Deimos) could be fragments of a tangent impact on Mars (Valles Marineris). As a further result was the loss of Mars' atmosphere. But my thoughts about this are even fewer than hypothetical... It is just my imagination; stuff for a SF novella.

Michael

MiR wrote:Seriously; is this scientifically veryfied?

No, his idea is a rather complicated explanation to a problem with much simpler solutions. It also creates more problems then it solves and uses some rather dodgy physics. It's much easier to just imagine Phobos starting sufficiently far from the planet (but within the synchronous orbit radius) that orbital decay would have delivered it to its current location. It just simply doesn't stand up all to Occam's razor. It's also likely that he's trolling, given that he posted the exact same thing here on the BAUT forum and then left.

MiR wrote:I always thought Phobos (and Deimos) could be fragments of a tangent impact on Mars (Valles Marineris).

Valles Marineris was formed by crustal stress associated with the Tharsis region.

MiR wrote:As a further result was the loss of Mars' atmosphere.

The loss of the Martian atmosphere was due to your typical atmospheric escape as you see hapenning at Earth and Venus. The main difference is that Earth and Venus are much more massive so as to avoid losing it so fast, and, unlike Mars, Earth has a strong internal dynamo to generate a magnetosphere.

Hungry4info wrote:The loss of the Martian atmosphere was due to your typical atmospheric escape as you see hapenning at Earth and Venus. The main difference is that Earth and Venus are much more massive so as to avoid losing it so fast, and, unlike Mars, Earth has a strong internal dynamo to generate a magnetosphere.

Oh yes, I already thought by myself; there must be such an unspectacular explanation...

Hm, and then it is also not true, that the martian population fled from Mars and crashed - about 65 million years ago - on our earth. And began, with much pleasure, to eat all of our dinosaurs... while we were still furred on four paws roaming the land at night and sipped the big dino eggs?

Hungry4info wrote:Valles Marineris was formed by crustal stress associated with the Tharsis region.

Hmmmh... I really don't know

Seriously; here I've found some interesting webpages of new insights about Phobos, please read:
http://www.bbc.co.uk/news/science-environment-11378762
http://www.europlanet-eu.org/outreach/index.php?option=com_content&task=view&id=304&Itemid=41
http://www.onorbit.com/node/2510

Michael

MiR wrote:

Hungry4info wrote:Valles Marineris was formed by crustal stress associated with the Tharsis region.

Hmmmh... I really don't know

Michael

Hi Michael, your dubds concernings Mars' impacts needs just to be assessed: they are actually taken into consideration within the driven mechanisms which played a role in the martian geology (martian dichotomy). Naively speaking, early impacts could be responsible to "move" and "concentrate" deeper hot magmas in some parts which rose up (in particular in the Tharsis regio), stretching and corrugating others.


http://jupiter.ethz.ch/~pjt/papers/Keller2009Icarus_Mars.pdf
http://www.es.ucsc.edu/~fnimmo/website/paper50.pdf
http://www.es.ucsc.edu/~fnimmo/website/paper50_SI.pdf
http://www.es.ucsc.edu/~fnimmo/website/Williams_et_al.pdf

Yes, Massimo, in principle I am d'accord with you and Hungry4info in regard to Mars' geological conditions. (I was only joking with my - more than hypothetical - explanations about Mars' history. Exept the Phobos related links)
On the other hand I have my doubts. Because the surface of Mars is very extremly aligned. Olympus Mons, Valles Marineris...
The longest and deepest canyon in our solar system and the highest mountain too.
Imagine (in relation to Mars) a mountain on our Earth with a height of 49 km! Or a valley 14 km deep... Mars really is a world of extremes.

And scientific research is changing the opinion sometimes faster than the weather change
E.g. : When I was young not one single serious astronomer were talking about extraterrestrial life, water on Mars or homecomputers too...

Michael

MiR wrote:...
The longest and deepest canyon in our solar system and the highest mountain too.
Imagine (in relation to Mars) a mountain on our Earth with a height of 49 km! Or a valley 14 km deep... Mars really is a world of extremes.
...
Michael

I understand your "vision". But no mountain on Earth could achieve such altitude because its equilibrium with the asthenosphere. (Airy's principle, isostasy, buoyancy) http://en.wikipedia.org/wiki/Isostasy
For instance, naively speaking, Himalaya cannot achieve hightest altitude because its lithosphere block is as thick as the distance amongst the crust and the asthenosphere; so when its mountain chain will have about 12-14 Km high, its lithosphere block will "sink" onto plastic asthenosphere, normalizing the equilibrium.
That Mars can have had a tectonic, is under debate. The Tarsis bulge is an indirect proof that no asthenosphere may be existed on Mars, and the superplume from deep is a possible hypotesis just because it shouldn't account for one asthenosphere (superplume will "shatter" all layers). the first PDF paper that I posted encompass all studies on the subject (even lateral stresses). There are also images of the computer's simulation.

If there was a moon x then this could account for the asteroid belt between mars and jupiter. That is, if it got smashed apart in the process - maybe through an incoming asteroid (which in turn saved Mars) or after it got pulled away from Mars orbit. I dont really buy this theory though. In light of the new data on Phobos, the hollow spaces/caverns, its very likely that this accounts for the strange orbit of Phobos. Spaceship or not...