Allan Hills 84001
ALH 84001 (official name: Allan Hills 84001 ) is 1.94 kg heavy meteorite, ( Victoria Land ) found on December 27, 1984 at the Allan Hills ice field in Antarctica and 1993 as the SNC Meteorite (Mars Meteorite ) was identified.
Description
It consists mainly of coarse-grained cataclastic Orthopyroxenit and therefore defines a new subgroup of the SNC meteorites, which is referred to as the SNC Orthopyroxenit. Compared to other Martian meteorites, which usually have a relatively young geological age, ALH 84001 is already very old. His age was determined by the lutetium -hafnium dating to 4.091 billion years. According to measurement of the irradiation age ALH 84001 was probably thrown off by the impact of an asteroid on Mars, about 15 million years ago from the surface of Mars and landed about 13,000 years ago on Earth.
In 1996, Dr. David S. McKay and his collaborators found in the Martian meteorite ALH 84001 structures, which they interpreted as traces of fossil bacteria. Their arguments for traces of fossil life in ALH 84001 are:
- Structures in electron micrographs, which are interpreted as fossilized bacteria. However, it is argued that these structures could also be artifacts of the recording technique used. In addition, the size of the structures in the range of only a few nanometers, and thus is much smaller than ordinary terrestrial bacteria. Although there have been " nanobacteria " discovered allegedly also on earth, so far however, this effect is even more controversial.
- Karbonateinschlüsse containing magnetite in a modification, such as it is produced to the earth bacteria. However, it has so far not be excluded that this magnetite may also be produced by non-biological processes.
- Polycyclic aromatic hydrocarbons (PAH, of Engl. Polycyclic Aromatic Hydrocarbons ) within the carbonates, which may arise from the decay of bacteria. Again, it is difficult to show that there are no non-biological processes which the same pattern of the PAHs generates as was found in the ALH 84001.
The theses of McKay and his co-authors are controversial to this day. There have now been found in two other Martian meteorites, Shergotty and Nakhla, possible relics from past lives. Among other things, on these structures is based on the theory of panspermia, according to which life on Earth is caused by germs from space.
Trivia
Dan Brown treated in his Thriller Meteor a supposedly discovered by NASA meteorite with inclusions of extraterrestrial life. The meteor is also called ALH 84,001th