Feb 14, 2024 08:47 PM
(This post was last modified: Feb 14, 2024 09:11 PM by C C.)
https://www.universetoday.com/165693/cos...he-galaxy/
EXCERPTS: Does life appear independently on different planets in the galaxy? Or does it spread from world to world? Or does it do both?
New research shows how life could spread via a basic, simple pathway: cosmic dust. [...] The research is titled “The Possibility of Panspermia in the Deep Cosmos by Means of the Planetary Dust Grains.” The sole author is Z.N. Osmanov, from the School of Physics at the Free University of Tbilisi in the country Georgia. The paper is in pre-print and hasn’t been published yet.
[....] “By obtaining the assumption that planetary dust particles can escape from the gravitational attraction of a planet, we consider the possibility for the dust grains to leave the star’s system by means of the radiation pressure,” Osmanov writes.
The idea that life itself could travel through space on comets and asteroids is familiar to many people [panpsermia]. When these objects crash into planets, the thinking goes, hitchhiking life is delivered, and if there’s a niche it can exploit, it will. But how could simple dust accomplish the same thing?
[...] Life would need to be very hardy to survive on a dust grain as it travels through interstellar space. It would have to avoid hazards like radiation and heat. If life itself couldn’t do it, maybe complex molecules that lead to life could. If we grant that it’s possible, the next question concerns how quickly it could spread.
“It has been shown that, during 5 billion years, the dust grains will reach 105 stellar systems, and by taking the Drake equation into account, it has been shown that the whole galaxy will be full of planetary dust particles,” Osmanov explains.
[...] It’s very interesting work. But the frustrating thing about this entire topic is that we still don’t know how life appears or how often it appears. So, all of our thought experiments and calculations, including Osmanov’s, have a stubborn nugget of the unknown at the centre...
[...] Osmanov claims that the number of planets with primitive life is enormous. We don’t know that. Planets are extraordinarily complex, and there are a bewildering number of variables. Even if there are an enormous number of planets with primitive life, many of them will be more massive than Earth. Will dust particles carrying life or complex organic molecules be able to escape the gravitational grasp of super-Earths, for example?
This research shows how life, or at least its building blocks, could escape from planets and survive the interstellar journey to another world.... (MORE - missing details)
EXCERPTS: Does life appear independently on different planets in the galaxy? Or does it spread from world to world? Or does it do both?
New research shows how life could spread via a basic, simple pathway: cosmic dust. [...] The research is titled “The Possibility of Panspermia in the Deep Cosmos by Means of the Planetary Dust Grains.” The sole author is Z.N. Osmanov, from the School of Physics at the Free University of Tbilisi in the country Georgia. The paper is in pre-print and hasn’t been published yet.
[....] “By obtaining the assumption that planetary dust particles can escape from the gravitational attraction of a planet, we consider the possibility for the dust grains to leave the star’s system by means of the radiation pressure,” Osmanov writes.
The idea that life itself could travel through space on comets and asteroids is familiar to many people [panpsermia]. When these objects crash into planets, the thinking goes, hitchhiking life is delivered, and if there’s a niche it can exploit, it will. But how could simple dust accomplish the same thing?
[...] Life would need to be very hardy to survive on a dust grain as it travels through interstellar space. It would have to avoid hazards like radiation and heat. If life itself couldn’t do it, maybe complex molecules that lead to life could. If we grant that it’s possible, the next question concerns how quickly it could spread.
“It has been shown that, during 5 billion years, the dust grains will reach 105 stellar systems, and by taking the Drake equation into account, it has been shown that the whole galaxy will be full of planetary dust particles,” Osmanov explains.
[...] It’s very interesting work. But the frustrating thing about this entire topic is that we still don’t know how life appears or how often it appears. So, all of our thought experiments and calculations, including Osmanov’s, have a stubborn nugget of the unknown at the centre...
[...] Osmanov claims that the number of planets with primitive life is enormous. We don’t know that. Planets are extraordinarily complex, and there are a bewildering number of variables. Even if there are an enormous number of planets with primitive life, many of them will be more massive than Earth. Will dust particles carrying life or complex organic molecules be able to escape the gravitational grasp of super-Earths, for example?
This research shows how life, or at least its building blocks, could escape from planets and survive the interstellar journey to another world.... (MORE - missing details)