New research reveals that as much as one half of all of Earth’s current water supply is older than the Sun.
An international team of scientists led by Ilse Cleeves at the University of Michigan looked back into creation of Earth and our solar system to find out where all of the water came from.
Some scientists think Earth’s supply of life-sustaining H2O was the result of chemical reactions that took place as the Sun and solar system began forming some 4.6 billion years ago.
Others theorize that today’s water originated about a million years earlier in the cold recesses of interstellar space from a molecular cloud that later provided material to form the sun and planets.
To reach their findings, Cleeves and her colleagues simulated the chemistry of our solar system as it was forming and then compared the ratio of two slightly different types of water, one that was plain H2O and the other, ‘heavier type’, that had been enriched with deuterium – an isotope of the hydrogen molecule.
The researchers found that the water in Earth’s oceans as ice found in comets have a higher ratio of the ‘heavy water’ to the deuterium free water than the Sun contains.
“That’s obviously a clue for what’s going on and it suggests that that very cold chemistry is required to produce these very large enrichments in the heavy isotopes deuterium in the water,” said Dr. Conel Alexander from the Carnegie Institution for Science, who was a member of the research team.
Alexander said that this very cold chemistry, about 10 to 30 degrees Kelvin – -263.15 to -243.15 Celsius – had to have ionizing radiation around in order to overcome the activation barriers that stop typical chemistry that takes place at the extremely cold temperatures.
The scientists considered two possible locations that may have allowed the cold chemistry.
One would be in the ancient molecular clouds (also called stellar nurseries) where stars form.
The other location would be in very cold regions of protoplanetary disks, which form solar system bodies such as planets, moons, asteroids, and others that surround developing stars.
But Cleeves realized that young stars that are surrounded by these planet-forming disks produce some very intense solar winds.
These solar winds, according to Alexander, would prevent galactic cosmic rays – one of the major sources of ionizing radiation – from even entering those disks, something that may very well stop deuterium-enriched water from forming.
This realization helped Cleeves create a complex model for the chemistry that existed within the planetary disks.
Alexander said the model did indeed show that deuterium-enriched water cannot be made in the disks, which led the group to conclude that it was produced within molecular clouds found in the interstellar medium.
“Ultimately, the intriguing idea is that you’re bringing in ices from the interstellar medium, pretty much intact, and those ices have a lot of organic material in them and some people have speculated that the organic material in meteorites and comets may have helped kick-start life,” said Alexander.
“If that’s true, and our solar system is fairly typical, then fairly similar superable organic material and water/ice is coming into most forming solar systems.”
This could, Alexander said, make the potential for life in other solar systems significantly more probable.
You can listen to the Science World radio interview with Dr. Conel Alexander either through the player below or check out the entire show at the times and places listed in the right side column.
A new report by the Global Carbon Project, an international science/environmental group, shows that the emission of carbon dioxide, one of the world’s top greenhouse gases – which scientists say leads to global warming – will not only rise once again in 2014, but will set a record high of 40 billion metric tons.
As the UN prepares to host its one day Climate Summit Tuesday at its New York headquarters, the report, which is an annual update to the group’s Global Carbon Budget, indicated that CO2 emissions that stem from fossil-fuel combustion and the production of cement grew by rate of 2.3 percent in 2013, with a record 36 billion metric tons of CO2 being produced. The report also predicted an additional 2.5 percent increase in CO2 emissions for 2014.
For a 66 percent chance of maintaining the UN’s Framework Convention on Climate Change goal of keeping average global warming to no more than 2 degrees Celsius, this new report indicates that the total amount of future CO2 emissions can’t exceed more than 1,200 metric tons.
The Global Carbon Project estimates that, at the current CO2 emission rate, this 1,200 metric ton quota would be used up in about 30 years.
The report shows that global CO2 emissions must be reduced by more than 5 percent each year over the next several decades to keep global warming below the 2 degrees Celsius goal.
Climate scientists contributing to the report said that unless new technologies to store carbon in the ground are developed and widely deployed, more than half of all the planet’s fossil fuel reserves may need to be left untouched to keep CO2 emissions below the 1,200 metric ton total.
“The human influence on climate change is clear,” said Professor Corinne Le Quéré, director of the Tyndall Center for Climate Change at the UK’s University of East Anglia in a press release. “We need substantial and sustained reductions in CO2 emissions from burning fossil fuels if we are to limit global climate change. We are nowhere near the commitments necessary to stay below 2 degrees Celsius of climate change, a level that will be already challenging to manage for most countries around the world, even for rich nations.”
Along with the CO2 emission projection for 2014, the update to the Global Carbon Budget also breaks the 2013 carbon dioxide emissions report into a country by country as well as a per capita breakdown.
Among the report’s key facts and figures:
- China, the USA, the EU and India are the largest emitters – together accounting for 58 per cent of emissions.
- China’s CO2 emissions grew by 4.2 per cent in 2013, the USA’s grew by 2.9 per cent, and India’s emissions grew by 5.1 per cent.
- The EU decreased its emissions by 1.8 per cent, though it continues to export a third of its emissions to China and other producers through imported goods and services.
- China’s CO2 emissions per person overtook emissions in the EU for the first time in 2013. China’s emissions are now larger than the US and EU combined. 16 per cent of China’s emissions are for goods and services which are exported elsewhere.
- CO2 emissions are caused primarily by burning fossil fuels, as well as by cement production and deforestation. Deforestation accounts for 8 per cent of CO2 emissions.
The Global Carbon Budget 2014 also includes a number of individual studies conducted by various research organizations who contributed to the report. These studies were published the journals, Nature Climate Change, Nature Geoscience and Earth System Science Data Discussions.
History of atmospheric CO2 from 800,000 years ago until January, 2012 (NOAA)
Two unmanned spacecraft headed to Mars, one launched by the United States and the other by India, will soon reach the Red Planet within days of each other.
NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) probe, launched November 18 is set for insertion into Mars orbit (MOI) on Sunday, September 21. India’s first interplanetary spacecraft, Mars Orbiter Mission (MOM), also known as Mangalyan, launched November 5 will be put into orbit around Mars on Wednesday, September 24.
MAVEN will study the specific processes that led to Mars losing much of its atmosphere about 3.5 billion years ago, something that could provide scientists with new insight about the evolution of the Red Planet as well as help solve the mystery of what happened to its water and carbon dioxide.
Some scientists say that billions of years ago, Mars had a rich atmosphere and was a warm and wet world. Others have speculated that the planet may have also had the right conditions to support microbial life.
University of Michigan Professor Stephen Bougher, who is also an investigator with the MAVEN team, told us that that it’s possible that the Martian H2O could have gone underground or was simple lost to space.
Among the immediate goals of the MAVEN mission, according to Bougher, is to find out how Mars’s upper atmosphere is connected to the solar wind that blows past the planet and how it strips away that upper atmosphere.
It’s possible that at some time during the early history of Mars the sun may have been much more active than today, producing a much more powerful solar wind that could have swept away Mars’ formerly lush atmosphere away like a broom sweeps dust and dirt.
Once scientists get answers to those present day questions, Bougher said the MAVEN team could run their computer models backwards in time to calculate what might have happened to Mars’s climate billions of years ago.
Data sent back to Earth from the MAVEN spacecraft could also help scientists gain a greater understanding of climate change on the planet and learn more of the history of planetary habitability.
The Indian Space Research Organization’s (ISRO) MOM satellite will orbit Mars for about a year, exploring the Martian surface and atmosphere.
Although not directly connected with ISRO’s mission, Bougher said that India’s spacecraft won’t get as close to the planet as MAVEN.
MOM also has a methane detection and measurement instrument onboard that will look for signs of the gas in the Martian atmosphere.
The detection of methane on Mars is considered by some to be controversial, especially since most methane here on Earth is produced biologically (such as from cow flatulence). But, some (less than 1%) of our methane has been produced by non-biological methods.
While some previous Earth based observations indicated the presence of methane on Mars, a year ago NASA delivered disappointing news that “after extensive tests” its Curiosity Rover could not find any sign of the gas on the Red Planet.
Along with its scientific goals of studying the Red Planet, ISRO has said that one of MOM’s other main objectives is to allow the Indian space program to develop the technologies required to design, plan, manage and operate an interplanetary mission.
You can listen to the Science World radio interview with Professor Stephen Bougher either through the player below or check out the entire show at the times and places listed in the right side column.
The emergence and rapid growth of antibiotic resistant bacteria has become a serious worldwide health concern.
The World Health Organization said in its 2014 report on antimicrobial resistance that “without urgent, coordinated action, the world is heading towards a post-antibiotic era, in which common infections and minor injuries, which have been treatable for decades, can once again kill.”
Scientists have found that some infection causing bacteria can quickly evolve and mutate to a point where antibiotics that were created to destroy it become ineffective. But now a team of researchers from three American universities have found that these mutating microbes can be sneakier that had been suspected.
The researchers, writing in the journal Biomicrofluidics, found that among the tools used by bacteria to avoid harm or destruction is a built-in arsenal of hidden genetic weapons that helps it develop a number of different ways to evolve and mutate quickly while under stress due to antibiotic treatments, making the microbes much more adaptable and tougher to beat.
“Bacteria are clever – they have hidden ways to respond to stress that involve re-sculpting their genomes,” said Princeton University biophysicist and team leader, Robert Austin in a press release. “It teaches us that antibiotics have to be used much more carefully than they have been up to this point,” he said.
Rather than using traditional test tubes or petri dishes, the researchers used unique fluid-filled microstructures in their experiments that were developed by Austin and his colleagues. The research team said that they think their new devices represented a more natural environment for their investigations than traditional laboratory implements.
“In complex environments the emergence of resistance can be far more rapid and profound than would be expected from test tube experiments,” Austin said.
So the team wondered if a mutated strain of E-coli, called GASP, would have the same type of antibiotic resistance as the “wild type” strain if it were exposed to the same drug.
To find out, the researchers sequenced the genomes of both “wild type” and the mutated GASP strains of E-coli bacteria that had been exposed to ciprofloxacin, an antibiotic medication known commonly as Cipro. The sequencing experiments showed that although the strains of the E-coli used different methods of genetic mutation, they all were able to develop comparable levels of antibiotic resistance.
Austin said that the research his team conducted revealed the wide range of tools bacteria can use to overcome stress and develop antibiotic resistance.
He also wondered about the effectiveness of other commonly used methods for killing potentially harmful microbes, such as using alcohol to sanitize germ ridden surfaces, and if bacteria would be able to develop a resistance to them as well.
Austin and his team are planning further tests.