Science & TechnologyS

Meteor

New comet may be visible with the naked eye

comet lulin
© Giovanni Sostero and Ernesto Guido, Remanzacco ObservatoryComet Lulin as seen on 2 January 2009. The image shows both the tail and the anti-tail.

Late next month Earth will receive a new celestial visitor named Lulin - or Comet C/2007 N3 - which astronomers say may have never visited this corner of the solar system before and should be visible to the naked eye.

Comets are icy clumps of dust and small rocks left over from the beginnings of the solar system. As they near the Sun some of the outer layer of ice is vaporised, releasing gas and solid debris that fans out into a tail pointing directly away from the Sun.

Astronomer and author Gary Kronk, based in St Jacob, Illinois, estimates that by 24 February, Lulin's gas tail should appear as long as around eight times the diameter of a full Moon. At that time it will be a mere 38 million miles from Earth, almost as close as Mars reaches to our planet.

Cow Skull

Evidence of 1.83 million-year human existence discovered

George Town: Universiti Sains Malaysia's Centre for Archaeological Research Malaysia has found evidence of early human existence in the country dating to 1.83 million years ago. The evidence was obtained through the discovery of artefacts in Bukit Bunuh, Lenggong, Perak.

The centre director Associate Professor Mokhtar Saidin said the evidence found included stone-made tools such as handaxe and chopping tools.

The artefacts were found embedded in suevite rock, formed as a result of the impact of meteorite crashing down at Bukit Bunuh.

Cloud Lightning

Exoplanet Sees Extreme Heat Waves

Exoplanet HD 80606b_01
One extrasolar planet takes heat waves to the extreme: Within six hours, temperatures on the gas giant can soar by more than 1,000 degrees Fahrenheit (555 degrees C).

The intense baking triggers shock-wave storms that whip around the planet quicker than the speed of sound, carrying with them skyrocketing heat and high-speed winds.

Known as HD 80606b, the gaseous planet was discovered in 2001 by a Swiss planet-hunting team led by Dominique Naef of the Geneva Observatory. It is about four times the mass of Jupiter and is located 200 light-years from Earth.

Sherlock

New Single-Element Compound Discovered

Florida International University researchers have discovered a new single-element compound, a breakthrough that could rewrite chemistry books.

The Center for the Study of Matters at Extreme Condition (CeSMEC) at FIU led an international group of scientists that synthesized and characterized a single-element compound, Boron Boride (B28).

The classic definition of a chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by mass. The new compound differs from that definition in that it is made up of just one element, formed by pure boron under high pressure and temperature (above 120,000 atmospheres and 1,400 degrees Celsius).

Star

What's Happening to the Sun? Could its unusual behavior herald a new ice age?

For about 50 years from roughly 1650 to 1700, the Sun took a break from its typical sunspot activity. That phase of solar rest coincided with what we now refer to as "The Little Ice Age" -- a period of cooling on the Earth that resulted in bitterly cold winters, particularly in Europe and North America. Scientists attribute the Little Ice Age to two main causes: increased volcanic activity and reduced solar activity.

Could it happen again? And are we headed there now?
The Sun
© NOAAThe First Cycle 24 Sunspot

Comment: According to the late Rhodes Fairbridge, the alignment of the Jupiter and Saturn, along with the minor planets, control the climate on Earth.
The sun's own orbit, he found, has eight characteristic patterns, all determined by Jupiter's position relative to Saturn, with the other planets playing much lesser roles. Some of these eight have orderly orbits, smooth and near-circular. During such orbits, solar activity is high and Earth heats up. Some of the eight orbits are chaotic, taking a loop-the-loop path. These orbits correspond to quiet times for the sun, and cool periods on Earth. Every 179 years or so, the sun embarks on a new cycle of orbits. One of the cooler periods in recent centuries was the Little Ice Age of the 17th century, when the Thames River in London froze over each winter. The next cool period, if the pattern holds, began in 1996, with the effects to be felt starting in 2010. Some predict three decades of severe cold.
And according Richard Mackey, writing in the Journal of Coastal Research (Special Issue 50, 2007):
In 2007 Ulysses will send information about the solar poles. This could be decisive regarding the predictions about emergent Sunspot Cycle No 24, including the sim hypothesis. According to the sim [Solar Inertial Motion] hypothesis, this cycle should be like Sunspot Cycle No 14, and be followed by two that will create a brief ice age. During the 1920s and '30s Australia's Bureau of Meteorology published research about the sun/climate relationship, especially Sunspot Cycle No 14, showing that it probably caused the worst drought then on record.
...

Rhodes Fairbridge repeatedly emphasised that the entire field of planetary-lunar-solar dynamics, including gravitational dynamics, has to be studied so the dynamics of terrestrial climate can be understood. An improved understanding of the interaction effects of the sunspot cycles and the lunisolar tidal cycles on the earth's climate is necessary, as Rhodes emphasised. When the influence of solar variability is examined in its entirety (as Rhodes insisted it should be), it is clear that the influence of solar variability on the Earth's climate is strongly non-linear, stochastic and significant.
...

The solar inertial motion hypothesis predicts that the period from about 2010 to 2040 will be one of relatively severe cold throughout the world. The hypothesis predicts that the emergent Sunspot Cycle No 24 will be quieter than Sunspot Cycle No 23 and just like Sunspot Cycle No 14, the weakest cycle in the last 100 years, which began in February, 1902 and ended in August,1913.
Not only has Ulysses found that the sun has reduced its output of solar wind to the lowest levels since accurate readings became available, but it's magnetic field has dropped by 20%. At the same time, the solar system appears to be passing through a galactic dust storm.
One possibility is an increased number of sporadic meteors, those not associated with known showers like the summer Perseids or the November Leonids. Meteors are created when something vaporizes in Earth's atmosphere. Space rocks as big as peas and baseballs crash through now and then, but most shooting stars are made of mere dust.

It's also possible, Landgraf said, that the eerie Zodiacal Light -- a "false dawn" caused by sunlight reflecting off space dust -- will be enhanced.

And in general, more material might rain down to Earth from space every year.
Indeed.

And we also know that during the previous ice age the depositional flux of cosmic dust was much higher than during the Holocene.

Gabrielli's paper shows that it was not the sun alone that caused the last ice age:

Depositional Fluxes
©Nature

It bears repeating astronomer Victor Clube's comment:
You first take the modern sky accessible to science, especially during the Space Age, and you look at its' darker debris with a view to relating its behavior to the more accessible human history which we can, in principle, really understand. And by this approach you discover from the dynamics of the material in space which I'm talking about that a huge comet must have settled in a Taurid orbit some 20,000 years ago, whose dense meteor stream for 10,000 years almost certainly produced the last Ice Age.



Bug

Common Chemical Causes Locusts to Swarm

A chemical that affects people's moods also can transform easygoing desert locusts into terrifying swarms that ravage the countryside, scientists report.

"Here we have a solitary and lonely creature, the desert locust. But just give them a little serotonin, and they go and join a gang," observed Malcolm Burrows of the University of Cambridge in England.

The brain chemical serotonin has been linked to mood in people. It plays a role in sexual desire, appetite, sleep, memory and learning, too.

Under certain conditions, locusts triple the amount of serotonin in their systems, changing the insects from loners to pack animals, Burrows and his co-authors report in Friday's edition of the journal Science.

Stormtrooper

Truck-mounted laser shoots down spy drone

mounted laser
© BoeingUncrewed drones have become popular with armed forces around the world and they are tricky to defend against, but a truck-mounted laser that can shoot them down could dilute their usefulness.

Uncrewed aerial vehicles are "revolutionary" technology that America must invest more in. Not the military's view, but that of President Obama in a statement on his defence priorities.

But a technology designed to make UAVs history is already showing promise - aerospace firm Boeing reports that their prototype truck-mounted laser has shot down a UAV at a missile range in New Mexico.

Uncrewed aircraft are powerful tools because they remove pilots from harm's way and because they can be built smaller than conventional spy or combat planes, making them harder to knock out of the sky.

UAVs come in all shapes and sizes: from the hand-launched Aerovironment Raven surveillance plane to the small airliner-sized Global Hawk.

Telescope

How was the solar system built?

Image
© T Pyle (SSC) / JPL-Caltech / NASA)This artist's concept depicts a distant hypothetical solar system, similar to the one recently discovered with the Spitzer Space Telescope. A narrow asteroid belt, filled with rocks and dusty debris, orbits a star similar to our own Sun when it was approximately 30 million years old (about the time Earth formed). Within the belt, a hypothetical planet also circles the star.

Looking at the planets of the solar system, you could be forgiven for thinking that if they do belong to the same family, it is by adoption rather than kinship. Not so: the story of the solar system's birth reveals that they are blood siblings, all created from the same molecular cloud whose collapse formed the sun. You might also think that these disparate bodies are scattered across the solar system without rhyme or reason. But move any piece of the solar system today, or try to add anything more, and the whole construction would be thrown fatally out of kilter. So how exactly did this delicate architecture come to be?

When our sun formed, it swallowed about 99.8 per cent of the debris cloud around it. According to the generally favoured picture, the lean pickings that remained were sculpted by gravity into a thin disc of gas and dust encircling the newborn star's midriff. As the dust grains of this disc orbited the sun, they collided and progressively coagulated into ever larger bodies. In the disc's innermost region, the ignition and burning of hydrogen in the sun made things very hot, so that only metals and silicate minerals with high melting points were present in solid form. Bodies in that region could only reach a certain size - producing the four small rocky planets of the inner solar system: Mercury, Venus, Earth and Mars.

Info

Hatred of slavery drove Darwin to emancipate all life

Image
© Library of Congress"Am I Not a Man and a Brother?" - the image of a slave in chains was cast in pottery by Josiah Wedgwood, Darwin's grandfather, and is used here to illustrate an 1837 anti-slavery poem.

For someone who came up with what has justly been described as "the single best idea anyone has ever had", Darwin has been vilified to an extraordinary degree. Clearly, his achievement of uniting all species under a common ancestor outraged millions, and still does. The book, Darwin's Sacred Cause, spectacularly humanises him, showing how he was driven by the great moral cause of his day: opposition to slavery.

Adrian Desmond and James Moore have come up with something astonishing: a radical new explanation of the force that drove Darwin. I hesitate to call this work definitive, as that was how the same authors' epic biography of Darwin was described in 1991. I wouldn't have thought it possible to further elevate the standing Darwin and his work have, but by trawling through reams of correspondence and notebooks, Desmond and Moore have done just that.

Darwin's family was passionately abolitionist and he continually mixed with people devoted to the cause. On his travels aboard the Beagle he was outraged by the suffering he saw inflicted by slavery, and that left a bigger impression on him than, say, the Galapagos finches.

Meteor

Mammoth-Killing Comet Questioned

mammoths
© BBC NewsWoolly mammoths were not the only ones to die out 13,000 years ago.
A study of wildfires after the last ice age has cast doubt on the theory that a giant comet impact wiped out woolly mammoths and prehistoric humans.

Analysis of charcoal and pollen records from around 13,000 years ago showed no evidence of continental-scale fires the cometary impact theory suggests.

However, the results showed increased fires after periods of climate change.