Phobos -

one of the mysteries in our solarsystem

Phobos, who is one of Mars two moons, has for a long time been surrounded of several rumours, where also a person like Carl Sagan think that it could be artificial. We are here going to take a closer look at this odd celestial body.

By: Anders Persson

Phobos was named after an attendant of the Roman war god Mars, and was discovered in 1877 by an astronomer named Ahsaph Hall. But with a diameter of only 25 km on his thickest point, I think that "asteroid" maybe is a more relevant name.
The period of revolution is 7 hours and 39 minutes it turn, precise like ours moon, the same side at Mars all the time. The surface of Phobos seems to be composed of stone with a great deal of carbon, but also a fraction of ice (that to explain Phobos low density). The general meaning among astronomers is that Phobos once in the time has been captured by the gravity of Mars. One of Phobos odd quality is that its mass seems to be lower than expected. The reason for that is the range of speedvariation during its elliptic cycle around Mars. The conclusion of that is that Phobos in one way or another should be hollow!

Hollow?

This cud point to measure or calculating error, because: How cud it be hollow?
If you look at picture of Phobos, then you will be striked about the grotesque big crater that's dominating one of the sides. The second thing that strikes you is the many parallel lines who goes from the crater and nearly reach the other end of the body, like the surface of a big melon.
The explanation to this lines is that it suppose to be cracks who arise from the impact of the big meteorite who is responsible for the big crater.
The question is; Is it cracks? If not, how has they arised?
Is it truly that this type of event creates parallel cracks in shapes of these that we can se on Phobos? DoesnÆt cracks follow natural lines of weakness in the mass of the body? ShouldnÆt not these cracks be bigger near the crater than far away from it?
If you look at small craters who's lying in these öcracksö you will have an impression that these have originated in the same timeperiod as the öcrackö itself. The reason for that, is that these small craters seems to follow these öcracksö like a perals on a necklace.

(Picture: P.J. Stooke. Morphografic Conformal Projection. Original mosaic by P.Thomas and D.Simonelli, November 1994.
Above pic=leading side,Longitud 90. Below pic=trailing side,longitud 270)

If you look at these small craters (both in- and outside these stripes) and note the shadow, you will se that several has his one half shadowed thus the light seems to falling more or less 90 degree from the surface. One conclusion of this is that the crater is built up in an asymmetric way, which in that way should lead to the conclusion that the impact have been maid up from the side. If that is the case, then why?
I must say that if you put all this together then it openes the possibility that these lines not are cracks, but rills or groove's from incoming meteorites. And they are in that case coming from nearly one direction. Now, why do I get hung up on this thing?
Well, if it is meteorites, why do they nearly came only from one direction? Is the explanation one single downpour of meteorites?
The question in that case is: Why do we not see such thing in other bodies like Phobos? Or do we?
A curious thing is that if you look at the border of the great crater, you will se that these lines seems to run over the border. This in fact can talk in benefit to the theory of cracks. But if itÆs really not cracks, but grooves? Then these grooves must have been there before the crater was made. But how can it runs over the border? How can they have ösurvivedö the impact of the big meteorite?
WouldnÆt these lines had been overthrown by melt rocks? This, in fact, is also the question if these lines really are cracks!

Speculations

Now we have came in to the section of speculation.
Of course, the speculation is dramatic, but what have you expected?
In my view, the reason to that these lines has survived the big impact could be that Phobos actually is hollow!
An impact under these circumstantials would, in my view, lead to that the crater chud give way inwards as a secondary reaction after that the primary crater has been made. Of course, cracks would not rise if the body are hollow.
Then, how is it with these striates or grooves, why are they only running in particular one way?
One explanation to this (besides that it was a downpour of meteorites) could be that Phobos have been travel a longer period in a very high speed in relation to other nearby celestial bodies!
The rate of impact would in that case be considerable but also, and thatÆs important, the impact would, more or less, come from one direction!
The rows of little craters in these grooves can in that case be explained by rolling and jumping meteorites that's blasting in to the side of the body and parallel to the surface!

Interstellar space travels

We shall now change subject for a while and talk about a problem in relation to long space travels, particular to other sunsystem. One of the main problem is the great risk of collision with different bodies of some kind. One way to solve this problem could be to shot dangerous objects into pieces by, for example, a lasercanon. The problem with that is that you instead have to deal with great amongst of fractions of these objects. Another and a easier way to handle the problem is to set a very big mass in front of the ship. There is in that case an advantage to make this big body hollow so that it can take up more energy in case of big impacts. Propulsion system and space for the crew can either be in these hollowed body or just behind it.

Phobos - a spaceship?

The dramatic question after all this is: Has Phobos been used as a such shield? Has somebody, in a distant time, visit our sunsystem? Has this thing any relation to these possibly made structures on Mars? Of course, with that material we in present time have, we can only speculating about these things. A curious thing is, that the two sonds, that in 1988 was send to Mars (and was intend to land on Phobos) by the Sovjetunion, both failed. One of the sond came very near Phobos before the contact was lost and the last photo, who was taken just before the contact was broken, shows a white line who stuck out from Phobos! A photographic error? Maybe, but why just before it died? Was it not permit to came so close? Or was it only a malfunction in the sond, maybe caused by a meteorite? Next summer we have, if we're lucky, three sonds around Mars again. Maybe we can receive some new photos of Phobos, and in that case have some new pieces who can help us to solve this pussle!