kidsneedscience:

Born on April 15, 1452, Leonardo Da Vinci was an Italian polymath and artist who was accomplished in many many fields.  One of his drawings depicted a screw-type flying machine that wasn’t physically built until several hundred years later who named it helicoptre, which gave the English word helicopter in 1861.  The word helicopter was a combination of the Ancient Greek words helix (in the form of the genitive, helikos) meaning spiral and pteron meaning wing, thus flying by a spiral wing. Today helicopters fly using a different principal, but the name remains. 

spaceplasma:

A Remarkable Outburst from an Old Black Hole

NASA’s Chandra X-ray Observatory has discovered an extraordinary outburst by a black hole in the spiral galaxy M83, located about 15 million light years from Earth. Using Chandra, astronomers found a new ultraluminous X-ray source (ULX), objects that give off more X-rays than most “normal” binary systems in which a companion star is in orbit around a neutron star or black hole.

On the left is an optical image of M83 from the Very Large Telescope in Chile, operated by the European Southern Observatory. On the right is a composite image showing X-ray data from Chandra in pink and optical data from the Hubble Space Telescope in blue and yellow. The ULX is located near the bottom of the composite image (mouseover for the exact position).

In Chandra observations that spanned several years, the ULX in M83 increased in X-ray brightness by at least 3,000 times. This sudden brightening is one of the largest changes in X-rays ever seen for this type of object, which do not usually show dormant periods.

Optical images reveal a bright blue source at the position of the ULX during the X-ray outburst. Before the outburst the blue source is not seen. These results imply that the companion to the black hole in M83 is a red giant star, more than about 500 million years old, with a mass less than about four times the Sun’s. According to theoretical models for the evolution of stars, the black hole should be almost as old as its companion.

Full Article

Credit:  Left image - Optical: ESO/VLT; Close-up - X-ray: NASA/CXC/Curtin University/R.Soria et al.,

The picture above is of our galactic center with a very weak aurora in the foreground. Scientists believe there is a supermassive black hole at our galactic center. Infra-red astronomy indicates an extremely massive 3-4 million solar mass object at the center with intense radio output. The intense radio output of this object is best modeled by matter being ground up as it spirals towards a supermassive object, creating two huge jets of extremely hot material.

mineralists:

Azurite with Malachite - National Mineral Collection

(via crownedrose)

freshphotons:

Surface Tension.

(via sagansense)

Jan. 24, 2013 — An insect with a tiny brain and minimal computing power has become the first animal proven to use the Milky Way for orientation. Scientists from South Africa and Sweden have published findings showing the link between dung beetles and the spray of stars which comprises our galaxy.

Although their eyes are too weak to distinguish individual constellations, dung beetles use the gradient of light to dark provided by the Milky Way to ensure they keep rolling their balls in a straight line and don’t circle back to competitors at the dung pile.

“The dung beetles don’t care which direction they’re going in; they just need to get away from the bun fight at the poo pile,” said Professor Marcus Byrne from Wits University.

Full Story

Water striders (Gerris remigis) are common water-walking insects approximately 1 centimeter long that resides on the surface of ponds, rivers and the open ocean. In the past, it was believed that water striders developed momentum using the tiny waves they generate as they flap their legs across the water’s surface. This was because striders move so quickly that all you see is the waves. But baby water striders legs are not big enough to generate waves, and therefore should be incapable of propelling themselves along the surface. So how are they able to move?

Enter John W.M. Bush, a mathematician from the Massachusetts Institute of Technology (MIT), and his team of researchers who, using high-speed video and blue-dyed water, tracked the movement of water striders. Bush’s high-speed images and dye studies show that the water strider propels itself by driving its central pair of legs in a sculling motion. In order for it to move, it must transfer momentum to the underlying fluid. Previously it was assumed that this transfer occured exclusively through capillary waves excited by the leg stroke, but Bush and his team found that, conversely, the strider transfers momentum to the fluid principally through dipolar vortices shed by its driving legs. The strider thus generates thrust by rowing, using its legs as oars, and the menisci beneath its driving legs as blades.

Above: NASA Infrared Telescope Facility

NASA employs the use of cryogenics for a variety of reasons, and researchers are constantly exploring new methods and applications in the hopes of continuously improving the technology. Here are just a few examples of how NASA utilizes cryogenics:

• Infrared Sensors: infrared rays, also called “heat rays” are given off by all warm objects. Infrared telescopes must be cold so that their own radiation doesn’t swamp the weak infrared signals from faraway astronomical objects. There will be infrared telescopes on the airborne infrared observatory SOFIA, the Stratospheric Observatory for Infrared Astronomy.

• Electronics: all sensors require electronics. Cooling electronics reduces the noise in the circuits and thus allows them to study weaker signals.

• X-rays: the sensors for XRS, the X-Ray Spectrometer measure temperature changes induced by incoming x-rays. When the sensors are colder, the induced temperature changes are larger and easier to measure.

sciencenote:

Chaos theory is the study of nonlinear dynamics, in which seemingly random events are actually predictable from simple deterministic equations.

In a scientific context, the word chaos has a slightly different meaning than it does in its general usage as a state of confusion, lacking any order. Chaos, with reference to chaos theory, refers to an apparent lack of order in a system that nevertheless obeys particular laws or rules; this understanding of chaos is synonymous with dynamical instability, a condition discovered by the physicist Henri Poincare in the early 20th century that refers to an inherent lack of predictability in some physical systems.

The two main components of chaos theory are the ideas that systems - no matter how complex they may be - rely upon an underlying order, and that very simple or small systems and events can cause very complex behaviors or events. This latter idea is known as sensitive dependence on initial conditions , a circumstance discovered by Edward Lorenz (who is generally credited as the first experimenter in the area of chaos) in the early 1960s.

Lorenz, a meteorologist, was running computerized equations to theoretically model and predict weather conditions. Having run a particular sequence, he decided to replicate it. Lorenz reentered the number from his printout, taken half-way through the sequence, and left it to run. What he found upon his return was, contrary to his expectations, these results were radically different from his first outcomes. Lorenz had, in fact, entered not precisely the same number, .506127, but the rounded figure of .506. According to all scientific expectations at that time, the resulting sequence should have differed only very slightly from the original trial, because measurement to three decimal places was considered to be fairly precise. Because the two figures were considered to be almost the same, the results should have likewise been similar.

…Newtonian laws of physics are completely deterministic: they assume that, at least theoretically, precise measurements are possible, and that more precise measurement of any condition will yield more precise predictions about past or future conditions….

we-are-star-stuff:

Astronomers searching for the building blocks of life in a giant dust cloud at the heart of the Milky Way have concluded that it would taste vaguely of raspberries.

The unanticipated discovery follows years of work by astronomers who trained their 30m radio telescope on the enormous ball of dust and gas in the hope of spotting complex molecules that are vital for life.

Finding amino acids in interstellar space is a Holy Grail for astrobiologists, as this would raise the possibility of life emerging on other planets after being seeded with the molecules.

In the latest survey, astronomers sifted through thousands of signals from Sagittarius B2, a vast dust cloud at the centre of our galaxy. While they failed to find evidence for amino acids, they did find a substance called ethyl formate, the chemical responsible for the flavour of raspberries.

“It does happen to give raspberries their flavour, but there are many other molecules that are needed to make space raspberries,” Arnaud Belloche, an astronomer at the Max Planck Institute for Radio Astronomy in Bonn, told the Guardian.

Curiously, ethyl formate has another distinguishing characteristic: it also smells of rum.

The astronomers used the IRAM telescope in Spain to analyse electromagnetic radiation emitted by a hot and dense region of Sagittarius B2 that surrounds a newborn star.

Radiation from the star is absorbed by molecules floating around in the gas cloud, which is then re-emitted at different energies depending on the type of molecule.

While scouring their data, the team also found evidence for the lethal chemical propyl cyanide in the same cloud. The two molecules are the largest yet discovered in deep space.

Dr Belloche and his colleague Robin Garrod at Cornell University in New York have collected nearly 4,000 distinct signals from the cloud but have only analysed around half of these.

“So far we have identified around 50 molecules in our survey, and two of those had not been seen before,” said Belloche.

Last year, the team came tantalisingly close to finding amino acids in space with the discovery of a molecule that can be used to make them, called amino acetonitrile.

The latest discoveries have boosted the researchers’ morale because the molecules are as large as the simplest amino acid, glycine. Amino acids are the building blocks of proteins and are widely seen as being critical for complex life to exist anywhere in the universe.

“The difficulty in searching for complex molecules is that the best astronomical sources contain so many different molecules that their ‘fingerprints’ overlap and are difficult to disentangle,” Belloche said.

The molecules are thought to form when chemicals that already exist on some dust grains, such as ethanol, link together to make more complex chains.

“There is no apparent limit to the size of molecules that can be formed by this process, so there’s good reason to expect even more complex organic molecules to be there,” said Garrod.