Post by Andrei Tchentchik on Aug 14, 2020 10:38:51 GMT 2
(.#463).- If there is life on Europa and Enceladus, does it come from Earth?
If there is life on Europa and Enceladus, does it come from Earth?
By: Yohan Demeure, scientific writer
January 6, 2020, 9 h 12 min
Credits : NASA/ESA/JPL/SSI/Cassini Imaging Team
What if life could jump from planet to planet and wait for some distant satellites? An American geophysicist favorable to this kind of theory carried out a rather interesting computer simulation. The latter relates to fragments of Earth that have potentially traveled to distant lands.
A fascinating theory
In the scientific world, many researchers are in favor of “lithopanspermia”. It is a scientific theory that life on Earth comes from accidental collisions with natural rocky extraterrestrial bodies (comets, meteorites, other planets). Some believe, for example, that life on Earth could have a Martian origin.
Lithopanspermia was discussed at the last American Geophysical Union rally, as reported by Space.com in a December 17 article. In the logic of this theory, the American geophysicist Jay Melosh tried to know if life could “jump” from planet to planet in order to colonize distant lands such as Europe and Enceladus, satellites of the planets Jupiter and Saturn.
Europe satellite of Jupiter and Enceladus satellite of Saturn ..
Credits: NASA / ESA / JPL-Caltech / SETI Institute
A simulation to find out more
Jay Melosh estimates that a very small number of fragments come into contact with Europe. According to the person concerned, this represents between 0.00004% and 0.00007% of the Martian rocks having touched the Earth. However, we estimate that a total of all the fragments of Mars arriving on our planet each year. In other words, 0.4 grams of these fragments would have reached Europe (about 0.2 grams in the case of Enceladus).
To arrive at this number, the geophysicist used a computer simulation having followed 100,000 particles of Martian rocks. The simulation takes into account an impact having propelled these fragments at speeds between 1.3 and 5 km / s. In addition, Jay Melosh estimates that the quantity of fragments having reached Europe is appreciably the same, in the case where the starting planet happens to be Earth rather than Mars. In other words, it is almost half a gram of rock probably carrying life.
However, if there is any life on these satellites, it is much more likely to be native. It is indeed very unlikely to come from Earth. As Jay Melosh points out, a fragment of rock travels about two billion years in space before reaching Europe!
F I N .
If there is life on Europa and Enceladus, does it come from Earth?
By: Yohan Demeure, scientific writer
January 6, 2020, 9 h 12 min
Credits : NASA/ESA/JPL/SSI/Cassini Imaging Team
What if life could jump from planet to planet and wait for some distant satellites? An American geophysicist favorable to this kind of theory carried out a rather interesting computer simulation. The latter relates to fragments of Earth that have potentially traveled to distant lands.
A fascinating theory
In the scientific world, many researchers are in favor of “lithopanspermia”. It is a scientific theory that life on Earth comes from accidental collisions with natural rocky extraterrestrial bodies (comets, meteorites, other planets). Some believe, for example, that life on Earth could have a Martian origin.
Lithopanspermia was discussed at the last American Geophysical Union rally, as reported by Space.com in a December 17 article. In the logic of this theory, the American geophysicist Jay Melosh tried to know if life could “jump” from planet to planet in order to colonize distant lands such as Europe and Enceladus, satellites of the planets Jupiter and Saturn.
Europe satellite of Jupiter and Enceladus satellite of Saturn ..
Credits: NASA / ESA / JPL-Caltech / SETI Institute
A simulation to find out more
Jay Melosh estimates that a very small number of fragments come into contact with Europe. According to the person concerned, this represents between 0.00004% and 0.00007% of the Martian rocks having touched the Earth. However, we estimate that a total of all the fragments of Mars arriving on our planet each year. In other words, 0.4 grams of these fragments would have reached Europe (about 0.2 grams in the case of Enceladus).
To arrive at this number, the geophysicist used a computer simulation having followed 100,000 particles of Martian rocks. The simulation takes into account an impact having propelled these fragments at speeds between 1.3 and 5 km / s. In addition, Jay Melosh estimates that the quantity of fragments having reached Europe is appreciably the same, in the case where the starting planet happens to be Earth rather than Mars. In other words, it is almost half a gram of rock probably carrying life.
However, if there is any life on these satellites, it is much more likely to be native. It is indeed very unlikely to come from Earth. As Jay Melosh points out, a fragment of rock travels about two billion years in space before reaching Europe!
F I N .
