Strong Evidence of Life in Ancient Lake at Mars Gale Crater

Scientists at NASA's Mars Science Laboratory have discovered evidence of an ancient lake on Mars that they believe may have supported life billions of years ago.

Using the Mars rover Curiosity, they analysed sedimentary rocks at Yellowknife Bay in the Gale Crater. Evidence from the analysis suggest that the site had at least one lake around 3.6 billion years ago. The analysis showed that the lake likely had fresh water and elements such as carbon, hydrogen, oxygen, nitrogen and sulphur which are suitable in sustaining life.

Compared to other previous Mars rovers, Curiosity is two times longer and five times heavier than the others. It carried equipment to gather samples of rocks and soil, process them and distribute them to onboard test chambers inside analytical instruments.

The Gale Crater, a depression made by an asteroid or comet billions of years ago, was the main target of Curiosity as it is believed to be made up of ancient sediment deposited when Mars still had abundant water at its surface.

Fossilized Pollen Suggests Flowering Plants Evolved 250 Million Years Ago

Fossilized pollen from the Triassic Period 250 million years ago
Credit: University of Zürich

Using Confocal Laser Scanning Microscopy, scientists have imaged fossilized pollen grains from Northern Switzerland that dates the evolution of flowering plants to the early Triassic Period around 252 to 247 million years ago. The three dimensional high resolution images of six different types of pollen also suggest that the plants were pollinated by insects.

The Triassic period extends to about 250 to 200 million years ago and is the first period of the Mesozoic Era. This period lies between the Permian and Jurassic periods.

During the Triassic period, the Earth's climate was generally hot and dry and that there are no evidence of glaciers at or near the north and south pole. During this time, the polar regions were moist and temperate. It would have a climate that is suitable for forests and vertebrarates.

The Earth's continents would not have existed then. The land mass of the planet then was one gigantic continent called Pangea. The climate on Pangea was seasonal having hot summers and cold winters.

Plant life during this time was believed to include lycophytes, cycads, ginkgophyta (represented in modern times by Ginkgo biloba) and glossopterids. Seed plants such as spermatophytes are abundant in the north while Glossopteris (a seed fern) was the dominant tree in the southern hemisphere.

The discovery of the pollen would place the appearance of flowering plants during this period, 100 million years earlier than previously believed.

Darwin's Evolution Through Natural Selection Consistent With Cambrian Explosion

This image shows marine life during the Cambrian explosion (~520 million years ago). A giant Anomalocaris investigates a trilobite, while Opabinia looks on from the right and the "walking cactus" Diania crawls underneath. All of these creatures are related to living arthropods.
Credit: Katrina Kenny & Nobumichi Tamura

Scientists report that Charles Darwin's evolution through natural selection theory is consistent with the sudden diversity of life during the Cambrian explosion. Their study shows that a sustained accelerated rate of evolution over millions of years would have resulted in an increased rate of over five times; 100 million years of evolutionary change would have only took about 20 million years.

580 million years ago, living organisms were mostly simple cells that occasionally organized into colonies. The following 70 to 80 million years suddenly showed a diverse amount of life that included animals, phytoplankton, and calcimicrobes.

This period of the Earth's history is called the Cambrian explosion. During this period, the evolutionary rate of living organisms accelerated and the diversity of living organisms began to resemble that of organisms today.

Fossil records have shown the results and aftermath of the Cambrian explosion but the reason for it to happen and why it has not repeated again is still a mystery.

Presence of Atmosphere and Water on Saturn Moon Titan Provides Deeper Understanding on Evolution of Life on Earth

At a symposium presented by the American Chemical Society, "Chemical Frontiers in Solar System Exploration", scientists have gathered to discuss the possibility and the circumstances that could lead to the evolution of life in one of the moons of Saturn, Titan.

Titan is one of the 62 satellites orbiting the planet Saturn. Located around one billion miles away from Earth, it is the only satellite in the solar system that is observed to have an atmosphere. The atmosphere consists of nitrogen and methane and also includes organic compounds such as ethane, acetylene, hydrogen cyanide, and cyanoacetylene.

The circumstances around Titan and its atmosphere closely resembles that of the Earth more than 3.5 billion years ago.

Data about Titan was gathered using the Huygens probe that landed on its surface on January 2005. For 90 minutes after touchdown, the probe transmitted its findings as well as images back to the Earth. The Huygens probe is the farthest landing for any craft launched from the Earth.

Based on the findings, Titan is the only object in the solar system apart from the Earth that contains large amounts of organic substances on the surface.

Mapping and DNA Sequencing the Genomes of Uncharted Microbial Organisms - Microbial Dark Matter

Great Boiling Spring in Nevada
Credit: Brian Hedlund, University of Nevada, Las Vegas

Scientists led by the U.S. Department of Energy Joint Genome Institute (DOE JGI) are mapping the genetic make up of previously uncharted branches in the bacterial and archaeal cells and organisms. These cells, referred to as "microbial dark matter" cannot be cultured in a laboratory and because they live in specific conditions and environments, are hard to reproduce.

Living organisms are divided into three kingdoms or domains, Eukaryota, Bacteria, and Archaea. They are classified based on their cellular organization, biochemistry, and molecular biology which each share on a fundamental basis with others in the domain regardless of the diversity.

Microbes are important to life. Bacteria, for example, comprises about 10% of a human body's weight and can be found in all organs and tissues. These organisms have great influence on a body's biological and even behavioral processes. The influence of microbial life is not restricted to the human body, it can also have influence over other areas such as the environment, global cycles, and also climate processes. A recent study points to microbes as the cause for rising methane levels in the ocean.

With this undertaking, scientists visited nine habitats around the world to collected uncultivated microbial cells from which they were able to reassemble and identify 201 distinct genomes. The data can be used to align with 28 major previously uncharted branches of the tree of life.

The nine habitats visited were Sakinaw Lake in British Columbia; the Etoliko Lagoon of western Greece; a sludge reactor in Mexico; the Gulf of Maine; off the north coast of Oahu, Hawaii, the Tropical Gyre in the south Atlantic; the East Pacific Rise; the Homestake Mine in South Dakota; and the Great Boiling Spring in Nevada.

Fossil of Helicoprion Reveals Secrets of Circular-saw like Teeth

An X-ray CT scan of a well preserved fossil of the Helicoprion reveals how the creature really looks like after years of conjecture.

The Helicoprion was a bizarre creature that lived during the Carboniferous Period around 270 to 300 million years ago. It was believed to be part of the shark family. It had a very distinct and unusual feature in that fossils show that its lower jaw had a circular-saw like set of sharp serrated teeth.

There was much debate on how the creature would look like with this set of teeth. The first fossils discovered of the Helicoprion were very incomplete and didn't really indicate how the creature would really look like. Because of that, there were many theories on how this circular set of teeth fit in with the Helicoprion.

There were some that theorized that the teeth were attached and curled up to a tongue like organ that can extend out similar to an elephant's trunk. Other's believe that the teeth were situated inside the creature's mouth. Other's even suggested that the circular groupings were located on the tail of the Helicoprion.

Although some discovered fossils showed hints of cartilaginous tissue, none have included the braincase or postcranial parts of these fish.

Japan Space Agency JAXA To Launch Spacecraft Hayabusa 2 To Rendezvous With Asteroid

Artist rendition of Hayabusa 2 departing from Earth
Credit: Hayabusa 2 project

The Japan Aerospace Exploration Agency (JAXA) is Japan's national aerospace agency. It was formed on October 01, 2003 and administered by the country's Ministry of Education, Culture, Sports, Science and Technology (MEXT) and the Ministry of Internal Affairs and Communications (MIC).

The responsibility of the agency is the research, development, and launch of satellites into orbit. Not confined to those projects, they are also actively involved in other missions such as asteroid exploration and possible manned exploration of the Moon.

JAXA's Hayabusa mission (launched 2003, returned 2010) was the first spacecraft ever to collect samples from an asteroid and return to Earth successfully. The target of the asteroid probe was Itokawa, an asteroid with a diameter of 500 meters. Using Earth's gravitational field and ion engines, Hayabusa reached the asteroid and provided scientists a first close look of a Near Earth Object(NEO).

Japanese spacecraft to search for clues of Earth's first life

Physics World's Dennis Normile reports that Japanese space agency, JAXA, plans to land a spacecraft on an asteroid in 2018. Its goal is to look for clues on how life began on Earth.

The spacecraft, named Hayabusa 2, is the second mission of JAXA at investigating and collecting data from an asteroid. The first mission, Hayabusa, returned to Earth in June 2010. Hayabusa 2 will be launched in 2014 with a view to settling on the targeted asteroid, named 1999 JU3, in mid-2018 before arriving back on Earth in 2020.

Hayabusa 2 will fire fingertip-sized bullets into the surface of the asteroid and the fragments from the impact will be collected. It will also detonate an impactor module, which will fire a 2 kg projectile into the asteroid to create a 2 m crater.

Astronomers Find Building Blocks of Life in Young Binary Star IRAS 16293-2422

This image shows an artist’s impression of glycolaldehyde molecules, showing glycolaldehyde’s molecular structure (C₂H₄O₂). Carbon atoms are shown as grey, oxygen atoms as red, and hydrogen atoms as white.
Credit:ESO/L. Calçada

Glycolaldehyde is a simplest form of sugar that can be found. The molecules of glycolaldehyde are smaller than the sugar used in food and drink (sucrose). The molecular formula for this compound is C₂H₄O₂.

Glycolaldehyde forms from many precursors, including the amino acid glycine. Glycine is a precursor to proteins which are essential to the formation of life. The NASA spacecraft Stardust confirmed the presence of glycine in comet Wild 2 which strengthened the theory that compounds required for life to flourish are present throughout the universe.

Glycolaldehyde has been detected in outer space twice; in 2000 in a gas cloud and within a star forming region in 2008.

Building Blocks of Life Found Around Young Star

A team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has spotted sugar molecules in the gas surrounding a young Sun-like star. This is the first time sugar been found in space around such a star, and the discovery shows that the building blocks of life are in the right place, at the right time, to be included in planets forming around the star.

The astronomers found molecules of glycolaldehyde — a simple form of sugar ^[1] — in the gas surrounding a young binary star, with similar mass to the Sun, called IRAS 16293-2422. Glycolaldehyde has been seen in interstellar space before ^[2], but this is the first time it has been found so near to a Sun-like star, at distances comparable to the distance of Uranus from the Sun in the Solar System. This discovery shows that some of the chemical compounds needed for life existed in this system at the time of planet formation ^[3].

A team of astronomers has found molecules of glycolaldehyde -- a simple form of sugar -- in the gas surrounding a young binary star, with similar mass to the Sun, called IRAS 16293-2422. This is the first time sugar been found in space around such a star, and the discovery shows that the building blocks of life are in the right place, at the right time, to be included in planets forming around the star. The astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect the molecules.

This image shows the Rho Ophiuchi star-forming region in infrared light, as seen by NASA’s Wide-field Infrared Explorer (WISE). IRAS 16293-2422 is the red object in the centre of the small square. The inset image is an artist’s impression of glycolaldehyde molecules, showing glycolaldehyde’s molecular structure (C₂H₄O₂). Carbon atoms are shown as grey, oxygen atoms as red, and hydrogen atoms as white.

In the WISE infrared image of Rho Ophiuchi, blue and cyan represent light emitted at wavelengths of 3.4 and 4.6 micrometres, which is predominantly from stars. Green and red represent light from 12 and 22 micrometres, respectively, which is mostly emitted by dust.
Credit: ESO/L. Calçada & NASA/JPL-Caltech/WISE Team

“In the disc of gas and dust surrounding this newly formed star, we found glycolaldehyde, which is a simple form of sugar, not much different to the sugar we put in coffee,” explains Jes Jørgensen (Niels Bohr Institute, Denmark), the lead author of the paper. “This molecule is one of the ingredients in the formation of RNA, which — like DNA, to which it is related — is one of the building blocks of life.”

The high sensitivity of ALMA — even at the technically challenging shortest wavelengths at which it operates — was critical for these observations, which were made with a partial array of antennas during the observatory’s Science Verification phase ^[4].

“What it is really exciting about our findings is that the ALMA observations reveal that the sugar molecules are falling in towards one of the stars of the system,” says team member Cécile Favre (Aarhus University, Denmark). “The sugar molecules are not only in the right place to find their way onto a planet, but they are also going in the right direction.”

The gas and dust clouds that collapse to form new stars are extremely cold ^[5] and many gases solidify as ice on the particles of dust where they then bond together and form more complex molecules. But once a star has been formed in the middle of a rotating cloud of gas and dust, it heats the inner parts of the cloud to around room temperature, evaporating the chemically complex molecules, and forming gases that emit their characteristic radiation as radio waves that can be mapped using powerful radio telescopes such as ALMA.

Life Expectancy Can Be Extended More Than 3 Years By Adjusting Sedentary Behavior

According to the the journal, Applied Physiology, Nutrition and Metabolism, Sedentary behavior is defined as "any waking activity characterized by an energy expenditure ≤ 1.5 metabolic equivalents and a sitting or reclining posture..."

This generally means that sedentary behavior involves any activity that the person does sitting or lying down. This includes watching television, playing video games, computer use, driving, and reading.

A study indicates that life expectancy in the USA would be 2 years higher if adults cut their sitting time to 3 hours a day and 1.38 years higher if television viewing time is cut to less than 2 hours a day.

This analysis is detailed in an article to be published in the online BMJ Open, Peter T Katzmarzyk of Pennington Biomedical Research Center, Louisiana State University System and I-Min Lee of the Division of Preventive Medicine, Brigham and Women’s Hospital and Harvard Medical School,

Several previous studies have linked extended periods spent sitting down and/or watching TV to poor health, such as diabetes and death from heart disease/stroke.

The researchers used data collected for the National Health and Nutrition Examination Survey (NHANES) for 2005/6 and 2009/10, to calculate the amount of time US adults spent watching TV and sitting down on a daily basis.

NHANES regularly surveys a large representative sample of the US population on various aspects of their health and lifestyle.

They trawled the research database MEDLINE, looking for published studies on sitting time and deaths from all causes, and pooled the different relative risk data from the five relevant studies, involving almost 167,000 adults. The database was then reanalysed, taking account of age and sex.

The Great Unconformity May Hold Key To How The Cambrian Explosion Started

Fossils between 530 to 550 million years old, started to show a diversity of animals embedded in it. This short period in the geological time scale is known as the Cambrian explosion.

The rapid appearance of most major animal phyla in the fossil record accompanied by major diversification of organisms including animals, phytoplankton, and calcimicrobes made the Cambrian explosion an important point in the history of life on Earth.

Before this period, around 580 million years ago, most living organisms were simple individual cells occasionally organized into colonies. The earlier Ediacaran period, 635 to 542 million years ago, also has a fossil history with macroscopic fossils of soft-bodied organisms. Over the following 70 or 80 million years from the start of the Cambrian explosion, the rate of evolution accelerated by an order of magnitude (as defined in terms of the extinction and origination rate of species) and the diversity of life began to resemble that of today.

Evidence for a geologic trigger of the Cambrian explosion

The oceans teemed with life 600 million years ago, but the simple, soft-bodied creatures would have been hardly recognizable as the ancestors of nearly all animals on Earth today.

Then something happened. Over several tens of millions of years – a relative blink of an eye in geologic terms – a burst of evolution led to a flurry of diversification and increasing complexity, including the expansion of multicellular organisms and the appearance of the first shells and skeletons.

The results of this Cambrian explosion are well documented in the fossil record, but its cause – why and when it happened, and perhaps why nothing similar has happened since – has been a mystery.

New research shows that the answer may lie in a second geological curiosity – a dramatic boundary, known as the Great Unconformity, between ancient igneous and metamorphic rocks and younger sediments.

Studying Earth Craters For Clues on Life On Mars

Earth, Mars, and the Moon

Earth is bigger than Mars. Earth is about two times the diameter of Mars. Nearly 70% of Earth is covered with liquid water; Mars has none. Although Mars may have had liquid water at one time in its early years.

Despite the differences, Mars is similar to Earth than any other planet in the solar systems. Mars, like Earth, has valleys and mountains, weather and seasons, and volcanoes and ice caps. At 24 hours and 39 minutes, the Martian day is only a little bit longer than Earth's. Because of these similarities, studying some geographical features in Earth helps scientists know more about Mars.

Asteroid craters on Earth give clues in search for life on Mars

Craters made by asteroid impacts may be the best place to look for signs of life on other planets, a study suggests.

Tiny organisms have been discovered thriving deep underneath a site in the US where an asteroid crashed some 35 million years ago.

Scientists believe that the organisms are evidence that such craters provide refuge for microbes, sheltering them from the effects of the changing seasons and events such as global warming or ice ages.

The study suggests that crater sites on Mars may also be hiding life, and that drilling beneath them could lead to evidence of similar life forms.

Deepest Underwater Volcanic Vent Full of Life

Deep down in the Caribbean seafloor, around 3.1 miles (5 kilometers) is the Cayman Trough. It is the world's deepest undersea volcanic vent. Known as "black smokers", these vents eject water hot enough to melt lead.

The undersea hot springs, which lie 0.5 miles (around 0.8 kilometers) deeper than any seen before, may be hotter than 450 °C and are shooting a jet of mineral-laden water more than a kilometer (0.62 miles) into the ocean above.

Despite these extreme conditions, the vents are teeming with thousands of a new species of shrimp that has a light-sensing organ on its back. And having found yet more 'black smoker' vents on an undersea mountain nearby, the researchers suggest that deep-sea vents may be more widespread around the world than anyone thought.