THE EARLY MARTIAN ATMOSPHERE
New research suggests that the early Martian atmosphere, 3.6 billion years ago, would have led to cold, dry conditions on the planet: Mars was not a permanently warm wet world.
http://www.bbc.co.uk/news/science-environment-27039711
The technique used was to calculate the early Martian atmospheric pressure from patterns of ancient meteor craters and dry river beds seen today on the Martian surface. If the atmosphere was thick, small meteors would burn up before reaching the surface; but some craters in the Aeolis Dorsa region near Gale Crater on Mars are small, only a few tens of metres across. suggesting quite small meteors survived through the thin atmosphere and impacted the surface.
Lead author Dr Edwin Kite said: ' Conditions were mostly very cold and very dry even on early Mars - similar to the Antarctic Dry Valleys on Earth today. However, there is still plenty of microbial life even in the Antarctic Dry Valleys so our work doesn't rule out an early environmental niche for life on Mars.'
It seems that surface water was not permanently present on early Mars, and that periods when the temperature got above freezing were rare or periodic.
Sunday, 20 April 2014
Friday, 18 April 2014
POTENTIAL BIRTH OF A MOON OF SATURN
Images captured last year by NASA's Cassini spacecraft of a small icy object within the outermost ring of Saturn may be evidence of the first stages of the formation of a new moon.
http://www.sciencedaily.com/releases/2014/04/140414180358.htm
The object is small - 750 miles long by 6 miles wide.
The report's lead author, Carl Murray of Queen Mary University of London, said 'We have not seen anything like this before. We may be looking at the act of birth, where this object is just leaving the rings and heading off to be a moon in its own right.'
The theory of the origin of Saturn's moons proposes that initially Saturn had a massive ring formation capable of giving birth to large moons. As the ring material depleted in this way, newly formed moons became smaller. The largest moons formed earlier, and are further away from the planet.
Cassini may have another opportunity to get more detailed images of the new object in late 2016, which could provide further evidence of the formation mechanism of Saturn's moon system.
Images captured last year by NASA's Cassini spacecraft of a small icy object within the outermost ring of Saturn may be evidence of the first stages of the formation of a new moon.
http://www.sciencedaily.com/releases/2014/04/140414180358.htm
The object is small - 750 miles long by 6 miles wide.
The report's lead author, Carl Murray of Queen Mary University of London, said 'We have not seen anything like this before. We may be looking at the act of birth, where this object is just leaving the rings and heading off to be a moon in its own right.'
The theory of the origin of Saturn's moons proposes that initially Saturn had a massive ring formation capable of giving birth to large moons. As the ring material depleted in this way, newly formed moons became smaller. The largest moons formed earlier, and are further away from the planet.
Cassini may have another opportunity to get more detailed images of the new object in late 2016, which could provide further evidence of the formation mechanism of Saturn's moon system.
Tuesday, 15 April 2014
THE SEARCH FOR DARK MATTER
A highly sensitive particle detector, located one mile underground in a cavern at the bottom of a former gold mine in the Black Hills of South Dakota, is an experiment searching for particles of dark matter.
http://www.bbc.co.uk/news/science-environment-26819792
The detector, called LUX, is inside a steel tank containing 70,000 gallons of pure water, free of any naturally occurring radioactivity that could interfere with the experiment. The detector contains 815 lb of liquid xenon. A dark matter particle interacting with the xenon would cause a tiny flash of light.
LUX failed to detect any of the dark matter particles, called weakly interacting massive particles (WIMPs) during a test run last year, but is now being re-run for a longer period of time.
Professor Rick Gaitskell of Brown University, one of the principal scientists leading the LUX search for dark matter, says 'The hypothesis we are working with at the moment is that a WIMP was the relic left-over from the Big Bang, and in fact dominates over the regular material you and I are made of'.
Dark matter may comprise about 85% of all the matter in the universe.
Other experiments are also searching for evidence of dark matter, including the Large Hadron Collider and space telescopes.
A highly sensitive particle detector, located one mile underground in a cavern at the bottom of a former gold mine in the Black Hills of South Dakota, is an experiment searching for particles of dark matter.
http://www.bbc.co.uk/news/science-environment-26819792
The detector, called LUX, is inside a steel tank containing 70,000 gallons of pure water, free of any naturally occurring radioactivity that could interfere with the experiment. The detector contains 815 lb of liquid xenon. A dark matter particle interacting with the xenon would cause a tiny flash of light.
LUX failed to detect any of the dark matter particles, called weakly interacting massive particles (WIMPs) during a test run last year, but is now being re-run for a longer period of time.
Professor Rick Gaitskell of Brown University, one of the principal scientists leading the LUX search for dark matter, says 'The hypothesis we are working with at the moment is that a WIMP was the relic left-over from the Big Bang, and in fact dominates over the regular material you and I are made of'.
Dark matter may comprise about 85% of all the matter in the universe.
Other experiments are also searching for evidence of dark matter, including the Large Hadron Collider and space telescopes.
Thursday, 10 April 2014
DARK ENERGY AND THE EXPANDING UNIVERSE
New measurements of the rate of expansion of the early universe indicate a slower expansion rate than expected.
http://www.bbc.co.uk/news/science-environment-26329320
The BOSS measurements were carried out using a 2.5 m telescope in New Mexico. While measurements of more recent expansion agree well with expected values, the early measurements around three billion years after the big bang give a slower rate than predicted.
BOSS team scientists at Portsmouth University say if further measurements with bigger samples confirm these findings, this may be an indication that the dark energy linked to the universe expansion is not a constant value as assumed, but varies in some way.
New measurements of the rate of expansion of the early universe indicate a slower expansion rate than expected.
http://www.bbc.co.uk/news/science-environment-26329320
The BOSS measurements were carried out using a 2.5 m telescope in New Mexico. While measurements of more recent expansion agree well with expected values, the early measurements around three billion years after the big bang give a slower rate than predicted.
BOSS team scientists at Portsmouth University say if further measurements with bigger samples confirm these findings, this may be an indication that the dark energy linked to the universe expansion is not a constant value as assumed, but varies in some way.
Wednesday, 2 October 2013
EXOPLANETARY SCIENCE
This new rapidly-growing field of scientific research is devoted not just to finding exoplanets but to discovering and analysing detailed information about them.
http://www.bbc.co.uk/news/science-environment-24348024
This report presents fascinating observations on an exoplanet Kepler-7b, which circles a star some 1,000 light years from Earth using Nasa's Spitzer and Kepler space telescopes. Brice-Olivier Demory of MIT interprets the measurements as a reflective signature of clouds on the exoplanet. Variations of the intensity of light from the parent star reflected from the exoplanet clouds yield information about the planetary cloud cover.
If this approach is extended to other (and closer to Earth) exoplanets among the hundreds of these planets already discovered beyond our solar system the research may reveal significant discoveries.
This new rapidly-growing field of scientific research is devoted not just to finding exoplanets but to discovering and analysing detailed information about them.
http://www.bbc.co.uk/news/science-environment-24348024
This report presents fascinating observations on an exoplanet Kepler-7b, which circles a star some 1,000 light years from Earth using Nasa's Spitzer and Kepler space telescopes. Brice-Olivier Demory of MIT interprets the measurements as a reflective signature of clouds on the exoplanet. Variations of the intensity of light from the parent star reflected from the exoplanet clouds yield information about the planetary cloud cover.
If this approach is extended to other (and closer to Earth) exoplanets among the hundreds of these planets already discovered beyond our solar system the research may reveal significant discoveries.
Tuesday, 1 October 2013
THE LEGACY OF FUKUSHIMA
This new critical analysis by Rupert Wingfield-Hayes exposes the devastating legacy of Fukushima, sounding a dire warning about the future of nuclear power.
http://www.bbc.co.uk/news/science-environment-24332012
His visit to a small town 5 miles from Fukushima is a poignant reminder of the human cost of the disaster. All the inhabitants have gone, still refugees two and a half years after the tsunami which wrecked the nuclear reactors at Fukushima. There is a huge task removing radioactive contaminated topsoil and trees within a 20 mile radius of ground zero. Where do you put it all? For how many hundreds of years?
Professor Kurokawa comments: 'Many senior bureaucrats from Japan's Nuclear Industry Safety Agency would take lucrative jobs in the nuclear industry after leaving government'.
Could it happen again? Wingfield-Hayes concludes that if the complacency prior to the disaster could happen in Japan, it can almost certainly happen elsewhere. The myth that it is safe has gone.
This new critical analysis by Rupert Wingfield-Hayes exposes the devastating legacy of Fukushima, sounding a dire warning about the future of nuclear power.
http://www.bbc.co.uk/news/science-environment-24332012
His visit to a small town 5 miles from Fukushima is a poignant reminder of the human cost of the disaster. All the inhabitants have gone, still refugees two and a half years after the tsunami which wrecked the nuclear reactors at Fukushima. There is a huge task removing radioactive contaminated topsoil and trees within a 20 mile radius of ground zero. Where do you put it all? For how many hundreds of years?
Professor Kurokawa comments: 'Many senior bureaucrats from Japan's Nuclear Industry Safety Agency would take lucrative jobs in the nuclear industry after leaving government'.
Could it happen again? Wingfield-Hayes concludes that if the complacency prior to the disaster could happen in Japan, it can almost certainly happen elsewhere. The myth that it is safe has gone.
Monday, 30 September 2013
CONFIRMATION OF WATER IN MARS SURFACE
A new paper by Laurie Leshin of the Rensselaer Polytechnic Institute in New York describes findings by the Mars Curiosity Rover instruments of water in the Martian surface.
http://www.bbc.co.uk/news/science-environment-24287207
Curiosity has travelled 400 metres from the touchdown site in Gale crater. Instruments have now recorded ~ 2% water vapour present in the dusty red covering over the Martian surface.
A new paper by Laurie Leshin of the Rensselaer Polytechnic Institute in New York describes findings by the Mars Curiosity Rover instruments of water in the Martian surface.
http://www.bbc.co.uk/news/science-environment-24287207
Curiosity has travelled 400 metres from the touchdown site in Gale crater. Instruments have now recorded ~ 2% water vapour present in the dusty red covering over the Martian surface.
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