Monday, November 20, 2017

Does Space Dust Transport Life Between Worlds?

The Greek word panspermia literally means "seeds everywhere". The panspermia hypothesis states that the "seeds" of life exist all over the Universe and can be propagated through space from one location to another. Some believe that life on Earth may have originated through these "seeds".

Life on our planet might have originated from biological particles brought to Earth in streams of space dust, a study suggests.

Fast-moving flows of interplanetary dust that continually bombard our planet’s atmosphere could deliver tiny organisms from far-off worlds, or send Earth-based organisms to other planets, according to the research.

High impact

The dust streams could collide with biological particles in Earth’s atmosphere with enough energy to knock them into space, a scientist has suggested.

Surrounded by an envelope of dust, the subject of this NASA/ESA Hubble Space Telescope image is a young forming star known as HBC 1. The star is in an immature and adolescent phase of life, while most of a sun-like star’s life is spent in a stable stage comparable to human adulthood.
Surrounded by an envelope of dust, the subject of this Hubble image is a young forming star
Credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

Such an event could enable bacteria and other forms of life to make their way from one planet in the solar system to another and perhaps beyond.

The finding suggests that large asteroid impacts may not be the sole mechanism by which life could transfer between planets, as was previously thought.

Fast flows

The research from the University of Edinburgh calculated how powerful flows of space dust – which can move at up to 70 km a second – could collide with particles in our atmospheric system.

It found that small particles existing at 150 km or higher above Earth’s surface could be knocked beyond the limit of Earth’s gravity by space dust and eventually reach other planets.

The same mechanism could enable the exchange of atmospheric particles between distant planets.

Some bacteria, plants and small animals called tardigrades are known to be able to survive in space, so it is possible that such organisms – if present in Earth’s upper atmosphere – might collide with fast-moving space dust and withstand a journey to another planet.

The study, published in Astrobiology, was partly funded by the Science and Technology Facilities Council.

The proposition that space dust collisions could propel organisms over enormous distances between planets raises some exciting prospects of how life and the atmospheres of planets originated. The streaming of fast space dust is found throughout planetary systems and could be a common factor in proliferating life.Professor Arjun BereraSchool of Physics and Astronomy

Fred Hoyle and Chandra Wickramasinghe have advanced the argument that various outbreaks of illnesses on Earth are of extraterrestrial origins, including the 1918 flu pandemic and certain outbreaks of polio and mad cow disease. For the 1918 flu pandemic they hypothesised that cometary dust brought the virus to Earth simultaneously at multiple locations—a view almost universally dismissed by external experts on this pandemic.

On 24 May 2003 The Lancet published a letter from Wickramasinghe, jointly signed by Milton Wainwright and Jayant Narlikar, in which they hypothesised that the virus that causes severe acute respiratory syndrome (SARS) could be extraterrestrial in origin instead of originating from chickens. The Lancet subsequently published three responses to this letter, showing that the hypothesis was not evidence-based, and casting doubts on the quality of the experiments referenced by Wickramasinghe in his letter. Claims connecting terrestrial disease and extraterrestrial pathogens have been rejected by the scientific community

From mid-November to early-December of in 2012 Sri Lanka witnessed a rare conjunction of natural phenomena, all pointing to the skies. Frequent sightings of meteors (probably the Leonids) were followed by numerous reports of fireballs, some of which actually resulted in the recovery of carbonaceous meteorites. Interest in all these events was heightened due to several episodes of red rain that fell in the same general timeframe and in the same locations. The red rain phenomenon of Sri Lanka was strikingly similar to the red rain of Kerala that was featured in a cover story in New Scientist of 4 March 2006.

Preliminary examination of the Sri Lankan red rain has shown the presence of red cells almost identical to the Kerala red rain cells. However, despite several years of study by various groups, the Kerala red rain cells have not yet been convincingly identified, and an extraterrestrial origin of the cells still remains a possibility. In the case of the Sri Lankan red rain cells, the mystery deepens with chemical analysis that shows them to contain unusually high concentrations of the elements arsenic and silver. The arsenic abundance is, however, less than a per cent of what would be required if phosphate groups in DNA are to be replaced by arsenate groups, as was recently suggested in studies of the bacterium strain GFAJ-1 of the Halomonadaceae (Science 332, 1163,2011), isolated from Mono Lake, California.

Optical microscope field of red rain cells

It would be tempting to connect the meteors and fireballs with the red rain events experienced in Sri Lanka during November and December 2012. Meteor showers (e.g. the Leonids) occur at regular times in the year whenever the Earth in its orbit crosses the trails of debris from short-period comets. Whilst centimetre-sized particles entering the atmosphere at high speeds burn-up as meteors or shooting stars, larger cometary fragments, containing dust and in some cases living cells, could disperse their particulate content non-destructively into the atmosphere. 

 Many years ago E.G. Bowen (Nature 117, 1121, 1956) discovered a connection between freezing nuclei in tropospheric rain clouds and the incidence of extraterrestrial particles from meteor streams. It was found that as dust from cometary streams (which may possibly include red rain cells) is introduced into the troposphere, heavy rain follows some 30 days later. Larger cometary bolides in a meteor stream that do not disintegrate could end up as fireballs and meteorites that fall to the ground.

Professor Chandra Wickramasinghe, Director of the Astrobiological Center at the Buckingham University is quoted as saying, “As far as the Kerala red rain is concerned, there is a mysterious microorganism that has defied identification so far. We have not been able to convincingly extract any DNA from them and Prof Louis has maintained that there is no DNA, but it can multiply at very high temperatures under high pressure conditions. I think there are all the signs of an alien bug! The Kerala red rain was preceded by a sonic boom that was heard, probably indicating that a fragment of a comet exploded in the atmosphere and unleashed the red cells that became incorporated in rain. I suspect the same could be true of the Sri Lankan rain, but I would like to have samples to confirm this. I should also say that reports of red rain are found throughout history all the way back to biblical times. I think this could be more evidence for cometary panspermia theory.”
Contacts and sources:
University of Edinburgh

Dr. Anil Samaranayake
Director, Medical Research Institute, Ministry of Health
Colombo, Sri Lanka

Prof. N. Chandra Wickramasinghe
Director Buckingham Centre for Astrobiology, Buckingham, UK

Citation: Space Dust Collisions as a Planetary Escape Mechanism. Astrobiology, 2017; DOI: 10.1089/ast.2017.1662 Click here to read the paper

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