MessageToEagle.com - Once upon a time, Earth was still a hot, violent place at this time, with volcanic
activity dominating the early Earth. The sky was cloudy and grey, keeping the heat in despite the sun being
weaker than today.
The water temperature of the oceans was much higher at 40-50 degrees (the temperature of a hot bath) and
circulating currents were very strong.
Any land masses were small, or about the size of Caribbean islands, and the tidal range was huge, a group of scientists
from the University of Western Australia and Oxford University say.
A few months ago, they found Earth's oldest fossils in Australia. These microscopic fossils show convincing evidence for cells and bacteria
living in an oxygen-free world over 3.4 billion years ago.
The team, led by Dr David Wacey of the University of Western Australia and including Professor Martin Brasier of
Oxford University, report the finding in the journal Nature Geoscience.
'At last we have good solid evidence for life over 3.4 billion years ago. It confirms there were bacteria at this
time, living without oxygen,' says Professor Brasier of the Department of Earth Sciences at Oxford.
Earth was still a hot, violent place at this time, with volcanic activity dominating the early Earth.
Significantly, there was very little oxygen present as there were no plants or algae yet to photosynthesise and produce oxygen.
The new evidence points to early life being sulfur-based, living off and metabolizing compounds containing sulfur rather
than oxygen for energy and growth.
'Such bacteria are still common today. sulfur bacteria are found in smelly ditches, soil, hot springs, hydrothermal vents --
anywhere where there's little free oxygen and they can live off organic matter,' explains Professor Brasier.
The microfossils satisfy three crucial tests that the forms seen in the rocks are biological and have not occurred
through some mineralization process.
The fossils are very clearly preserved showing precise cell-like structures all of a similar size. They look like
well known but much newer microfossils from 2 billion years ago, and are not odd or strained in shape.
The microfossils were found in a remote part of Western Australia called Strelley Pool. They are very well preserved
between the quartz sand grains of the oldest beach or shoreline known on Earth, in some of the oldest sedimentary rocks
that can be found anywhere.
'We can be very sure about the age as the rocks were formed between two volcanic successions that narrow the possible
age down to a few tens of millions of years,' says Professor Brasier. 'That's very accurate indeed when the rocks are
3.4 billion years old.'
Oldest Fossils This cluster of cells is one example of the spheroidal and ellipsoidal microfossils found at
the 3.4-billion-year-old Strelley Pool Formation in Western Australia. David Wacey/University of Western Australia
The fossils suggest biological-like behavior. The cells, clustered in groups, are only present in appropriate
habitats and are found attached to sand grains.
They show biological metabolisms. The chemical make-up of the tiny fossilized structures is right, and
crystals of pyrite (fool's gold) associated with the microfossils are very likely to be by-products of the sulfur
metabolism of these ancient cells and bacteria.
The researchers are now try to re-examine other fossil discoveries that have been proposed to contain evidence for
life on Earth at these extremely early times.
'We're now making detailed comparisons with all other early microfossils, and we're very optimistic for
future finds,' says Professor Brasier.
The work also has implications for looking for life on other planets, giving an indication of what evidence
for such life might look like.
Should there be life elsewhere in our solar system -- on Mars or on the moons of Titan or Europa -- it is
likely to be similar sorts of bacteria and cells living in similar environments. So any fossils in rocks from
these planets and moons ought to look like these Australian microfossils and pass the same evidence tests.
'Could these sorts of things exist on Mars? It's just about conceivable,' says Professor Brasier.
'But it would need these approaches -- mapping the chemistry of any microfossils in fine detail and convincing
three-dimensional images -- to support any evidence for life on Mars.'
Antarctica's Mysterious Lake Untersee And Its Otherworldly Ecosystem
A research team has now returned to Lake Untersee to begin the first real studies of this incredible environment.
This new high-quality image details the conical stromatolites that have formed on top of a boulder at a depth of about 20 meters, other
cones can be seen populating the sloping bottom...
Hidden Misshapen Celestial "Wonder"
It is one of the brightest and strangest objects in the Milky Way - the corpse of a star that exploded around 1000 years ago.
Only a handful of such young supernova remnants are known.
The object named G350.1-0.3 is also incredibly small (only eight light years across) and young in astronomical terms.
Alien Species Living In The Inner Milky Way Could Be In Danger
Few people doubt there is intelligent alien life in the Milky Way galaxy, but where can we expect to find it?
Astronomers think that while the inner sector of the MIlky Way Galaxy may be the most likely to support habitable worlds.
Unfortunately some of these places are also most dangerous to all life-forms.
Black Holes With No 'Table Manners' Eat Two Courses At Once!
It is still unknown how the supermassive black holes (SMBH) in galaxy centres accrete gas and grow.
Researchers from the University of Leicester (UK) and Monash University in Australia have investigated how some black holes got so big so fast that they are billions of times heavier than the sun.
Mercury Surprises Scientists
On March 17, MESSENGER (MErcury Surface, Space Environment, GEochemistry, and Ranging) completed its one-year primary mission, orbiting Mercury, capturing nearly 100,000 images, and recording data
that reveals new information about the planet's core, topography, and the mysterious radar bright material in the permanently shadowed areas near the poles.
Living Earth Simulator - Supercomputer Predicting The Future
In Douglas Adams book the Hitchhikers Guide to the Galaxy we encounter a machine called Deep Thought. It is the most powerful computer ever built. Deep Thought is capable of answering questions
concerning life, the Universe, and simply everything. Now scientists are planning to create a similar machine. It is called the Living Earth Simulator (LES).
Warp-Speed Planets Are Some Of The Fastest Objects In The Milky Way
Warped planets are some of the fastest objects in the Milky Way and they zoom through space near the speed of light.
Some years ago astronomers were astonished when they they found the first runaway star flying out of our Galaxy at a speed of 1.5 million miles per hour.
The discovery intrigued theorists, who wondered: If a star can get tossed outward at such an extreme velocity, could the same thing happen to planets?
Though the universe is filled with billions upon billions of stars, the discovery of a single variable star in 1923 altered the
course of modern astronomy. And, at least one famous astronomer of the time lamented that the discovery had shattered his world view.
Astronomical Mystery - Tremendous Explosion And Appearance Of Odd Rings
Twenty five years ago, on 1987 February 23, the brightest supernova of modern times was observed in the Large Magellanic Cloud.
The collision occurred at speeds near 60 million kilometers per hour and shock-heats the ring material causing it to glow.
Over time, astronomers have watched and waited for the expanding debris from this tremendous stellar explosion to crash into previously expelled material...
The "Cloaked" Star Was Difficult To Find
An object obscured by dust, and buried in a two-star system enshrouded by dense gas, is not easy to find.
A "cloaked" star was discovered after it ate a little of its neighbor. The meal must have given the star a bit of indigestion, because it
"burped" with a blast of high-energy radiation, which gave it away.