Earth Life-Forms Could Be Across The Universe

Most scientists believe life exists on other planets, but where could it have come from? Spontaneous creation? The result of a serendipitous combination of minerals in some primordial sludge? Or could we inadvertently have put it there?

Some European and American scientists at the Cardiff Centre for Astrobiology in England believe the latter is most likely.

According to two papers published recently in the Monthly Notices of the Royal Astronomical Society, life that originated on Earth may be spread out all over the galaxy in the hearts of comets. And these comets might be seeding other planets with Earth-like lifeforms. The implications of this theory may cause a ruckus in astronomical circles across the globe.

The theory of panspermia, the belief that life is seeded on planets from an outside source, is an ancient one. The Greek philosopher Anaxagoras first introduced the idea in philosophical circles in the fifth century B.C. He theorized that life is made up of smaller units, or “seeds” that break down in stages into smaller and smaller bits. These minute bits may float about in the cosmos spreading life wherever they go.

Aristotle disagreed with Anaxagoras’ conclusions and decreed that life was a spontaneous event – an idea that was widely accepted by philosophers, theologians and scientists alike, and that still clings to the forefront of life origin theories to this day.

Space travel

In retrospect, we know that Anaxagoras was correct about complex life being made up of smaller units (cells, molecules, atoms), but was he right that it could spread from planet to planet?

Modern discoveries are suggesting he was.

In 1984 a meteorite was discovered on the ice fields of Allen Hills, Antarctica. It was boxed up and virtually forgotten for more then a decade. In 1996 scientists recovered the rock and began to study its unique nature.

They soon discovered the rock was not only from Mars, but that it had what appeared to be fossils of rope-like bacteria inside it. Since this discovery, more recent comparisons of these fossil structures and living bacterial structures in the mud of Queensland, Australia, seem to support the idea that life here may actually have come from Mars.

However, the heated debate about whether these structures are fossils of ancient Martian bacterium or just some natural structure in the stone still rages.

The scientists at the Cardiff Centre have taken the idea of panspermia one logical step further. If life came here from somewhere else, perhaps hitching a ride on a hunk of Mars rock blasted off by an ancient impact, then how many places are now hosting microbes blasted off the Earth during any number of meteor, asteroid, or comet strikes over the past 3.5 billion years? In fact, perhaps the life on the Mars rock was life from Earth hitching a ride back home.

It is assumed that large boulders and other debris can be blasted off the Earth during a massive impact event. The Earth has been blasted in such a manner numerous times throughout its history.

This material may be infested with hardy bacterial spores and other Earthling microbes that could survive the hostile environment of interplanetary space quite easily – especially if these life- forms are nestled deep inside the rock where radiation can’t get to it.

Eventually, as the boulder is bumped and ground down into smaller bits during its ride through the solar system, it could be pushed out of our system by the solar wind.

If this is true, the Cardiff scientists theorize, our solar system could be surrounded by an ever-expanding “biodisc,” a ring of life-seeded material stretching some 30 or more light-years across.

Our sun – and the whole system with it – makes one revolution around the galactic center every 240 million years, so we have made quite a few trips around in the 3.5 billion years life has had a foothold on this rock of ours.

The theory submits this expanding “biodisc” would have already come in contact, and “infected,” more than 10,000 million systems throughout the galaxy already.

SkyLights

– Today: This evening a small telescope will show three of Jupiter’s moons – Io, Europa, and Callisto – forming a tight grouping. They’re closest together around 11 p.m. Find Jupiter rising in the east around 7:30 p.m. It is high in the east around 10 p.m.

– Friday: New Moon, exact at 4:18 a.m.

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