Vitamin B3 comes from SPACE: Niacin finding supports theories of extraterrestrial origins for life on Earth
- Supernovae explosions produce vast dust clouds in space that compress
- Layers of frost made of various gases form on these dust particles
- Radiation powers chemical reactions producing organic molecules on dust
- Ice becomes part of comets which then deliver organic molecules to Earth
By Jack Millner For Mailonline
Vitamin B3 found on Earth might have been made in space and delivered to Earth on meteorites, according to Nasa.
The vitamin forms part of a chemical compound that is found in all living cells and is an essential building block for life.
The finding supports theories that some of the organic material needed for life had extraterrestrial origins and arrived on Earth on comets and meteors.
The vitamin B3 forms part of a chemical compound that is found in all living cells and is an essential building block for life. Pictured is an artist's impression of a protoplanetary disk which contains dust particles with an icy frost that end up in comets, possibly bringing organic compounds to Earth
Vitamin B3, also known as niacin, is a component of a chemical compound called nicotinamide adenine dinucleotide (NAD) which is essential for metabolism and thought to be ancient in origin.
'We found that the types of organic compounds in our laboratory-produced ices match very well to what is found in meteorites,' said Karen Smith of Nasa's Goddard Space Flight Center in Greenbelt, Maryland.
'This result suggests that these important organic compounds in meteorites may have originated from simple molecular ices in space.
'This type of chemistry may also be relevant for comets, which contain large amounts of water and carbon dioxide ices.
THE PANSPERMIA HYPOTHESIS
- Pamspermia is the hypothesis that life exists throughout the universe and is spread by asteroids and comets, in addition to simply drifting through the cosmos.
- Panspermia proposes that life forms that can survive the effects of space, such as extremophiles, become trapped in debris that is ejected into space after collisions between asteroids and planets that harbour life.
- These life-forms may travel dormant for an extended amount of time before colliding randomly with other planets or intermingling with protoplanetary disks.
- Alternatively organic molecules - the building blocks for life - could have been delivered to Earth via comets.
'These experiments show that vitamin B3 and other complex organic compounds could be made in space and it is plausible that meteorite and comet impacts could have added an extraterrestrial component to the supply of vitamin B3 on ancient Earth.'
Supernovae explosions produce vast dust clouds in space that then compress under their own gravity, giving birth to solar systems.
Layers of frost - made from carbon dioxide, water and other gases - form on these dust particles just like frost builds up on a car window on a cold night.
Radiation in space powers chemical reactions in this frost layer to produce complex organic molecules, possibly including vitamin B3, according to researchers.
These icy grains become incorporated into comets and asteroids, some of which end up colliding with young planets like Earth, delivering their organic molecules.
To simulate this process, Nasa researchers created cold space-like conditions in their Cosmic Ice Laboratory at Nasa Goddard.
Nasa researchers simulated conditions in space to try to make vitamin B3 from ice that they then bombarded with radiation. Pictured, the chemical deposit made by Nasa researchers
Gases were released into the vacuum chamber where they froze, then researchers bombarded them with protons to simulate space radiation.
The experiment produced a variety of complex molecules including vitamin B3.
'Rosetta could help validate these experiments if it finds some of the same complex organic molecules in the gases released by the comet or in the comet's nucleus,' said Smith.
The study builds on previous work that showed that vitamin B3 was present in carbon-rich meteorites.
In that work the team showed vitamin B3 could be made from a building-block organic molecule called pyridine in carbon dioxide ice under conditions found in space.
The new experiments involved adding water ice to the mixture, with researchers finding that even with the addition of water, the vitamin could be made under a wide variety of scenarios where the amount of water ice varied.
'This work is part of a broad research program in the field of Astrobiology at Nasa Goddard,' said Perry Gerakines, Smith's postdoctoral research advisor.
'We are working to understand the origins of biologically important molecules and how they came to exist throughout the Solar System and on Earth.
'The experiments performed in our laboratory demonstrate an important possible connection between the complex organic molecules formed in cold interstellar space and those we find in meteorites.'
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