Limits...
Spore-Forming Thermophilic Bacterium within Artificial Meteorite Survives Entry into the Earth's Atmosphere on FOTON-M4 Satellite Landing Module.

Slobodkin A, Gavrilov S, Ionov V, Iliyin V - PLoS ONE (2015)

Bottom Line: So far, all experimental proof of this possibility has been based on tests with sounding rockets which do not reach the transit velocities of natural meteorites.The identity of the strain was confirmed by 16S rRNA gene sequence and physiological tests.This is the first report on the survival of a lifeform within an artificial meteorite after entry from space orbit through Earth's atmosphere at a velocity that closely approached the velocities of natural meteorites.

View Article: PubMed Central - PubMed

Affiliation: Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312 Moscow, Russia.

ABSTRACT
One of the key conditions of the lithopanspermia hypothesis is that microorganisms situated within meteorites could survive hypervelocity entry from space through the Earth's atmosphere. So far, all experimental proof of this possibility has been based on tests with sounding rockets which do not reach the transit velocities of natural meteorites. We explored the survival of the spore-forming thermophilic anaerobic bacterium, Thermoanaerobacter siderophilus, placed within 1.4-cm thick basalt discs fixed on the exterior of a space capsule (the METEORITE experiment on the FOTON-M4 satellite). After 45 days of orbital flight, the landing module of the space vehicle returned to Earth. The temperature during the atmospheric transit was high enough to melt the surface of basalt. T. siderophilus survived the entry; viable cells were recovered from 4 of 24 wells loaded with this microorganism. The identity of the strain was confirmed by 16S rRNA gene sequence and physiological tests. This is the first report on the survival of a lifeform within an artificial meteorite after entry from space orbit through Earth's atmosphere at a velocity that closely approached the velocities of natural meteorites. The characteristics of the artificial meteorite and the living object applied in this study can serve as positive controls in further experiments on testing of different organisms and conditions of interplanetary transport.

No MeSH data available.


Related in: MedlinePlus

FOTON-M4 landing module after landing, showing the placement of the discs around the stagnation point.Two of four discs fixed near the stagnation point were used in this part of the METEORITE experiment.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4494708&req=5

pone.0132611.g003: FOTON-M4 landing module after landing, showing the placement of the discs around the stagnation point.Two of four discs fixed near the stagnation point were used in this part of the METEORITE experiment.

Mentions: In the METEORITE experiment, four basalt discs loaded with dried microbial cultures (Fig 1) were fixed on the exterior of the space capsule of the FOTON-M4 satellite. After 45 days of orbital flight, the landing module was returned to Earth (Fig 3). Discs #1 and #2 were exposed to conditions of orbital flight and hypervelocity entry from space through the atmosphere (test). Discs #3 and #4 were exposed to conditions of orbital flight but were protected from heating during reentry by the radio-controlled lids (orbital control). Two other discs (#5 and #6) were kept in the laboratory at ambient temperature (ground control).


Spore-Forming Thermophilic Bacterium within Artificial Meteorite Survives Entry into the Earth's Atmosphere on FOTON-M4 Satellite Landing Module.

Slobodkin A, Gavrilov S, Ionov V, Iliyin V - PLoS ONE (2015)

FOTON-M4 landing module after landing, showing the placement of the discs around the stagnation point.Two of four discs fixed near the stagnation point were used in this part of the METEORITE experiment.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494708&req=5

pone.0132611.g003: FOTON-M4 landing module after landing, showing the placement of the discs around the stagnation point.Two of four discs fixed near the stagnation point were used in this part of the METEORITE experiment.
Mentions: In the METEORITE experiment, four basalt discs loaded with dried microbial cultures (Fig 1) were fixed on the exterior of the space capsule of the FOTON-M4 satellite. After 45 days of orbital flight, the landing module was returned to Earth (Fig 3). Discs #1 and #2 were exposed to conditions of orbital flight and hypervelocity entry from space through the atmosphere (test). Discs #3 and #4 were exposed to conditions of orbital flight but were protected from heating during reentry by the radio-controlled lids (orbital control). Two other discs (#5 and #6) were kept in the laboratory at ambient temperature (ground control).

Bottom Line: So far, all experimental proof of this possibility has been based on tests with sounding rockets which do not reach the transit velocities of natural meteorites.The identity of the strain was confirmed by 16S rRNA gene sequence and physiological tests.This is the first report on the survival of a lifeform within an artificial meteorite after entry from space orbit through Earth's atmosphere at a velocity that closely approached the velocities of natural meteorites.

View Article: PubMed Central - PubMed

Affiliation: Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312 Moscow, Russia.

ABSTRACT
One of the key conditions of the lithopanspermia hypothesis is that microorganisms situated within meteorites could survive hypervelocity entry from space through the Earth's atmosphere. So far, all experimental proof of this possibility has been based on tests with sounding rockets which do not reach the transit velocities of natural meteorites. We explored the survival of the spore-forming thermophilic anaerobic bacterium, Thermoanaerobacter siderophilus, placed within 1.4-cm thick basalt discs fixed on the exterior of a space capsule (the METEORITE experiment on the FOTON-M4 satellite). After 45 days of orbital flight, the landing module of the space vehicle returned to Earth. The temperature during the atmospheric transit was high enough to melt the surface of basalt. T. siderophilus survived the entry; viable cells were recovered from 4 of 24 wells loaded with this microorganism. The identity of the strain was confirmed by 16S rRNA gene sequence and physiological tests. This is the first report on the survival of a lifeform within an artificial meteorite after entry from space orbit through Earth's atmosphere at a velocity that closely approached the velocities of natural meteorites. The characteristics of the artificial meteorite and the living object applied in this study can serve as positive controls in further experiments on testing of different organisms and conditions of interplanetary transport.

No MeSH data available.


Related in: MedlinePlus