Implicit Differentiation

cozydark:

NASA Views Our Perpetual Ocean |

The swirling flows of tens of thousands of ocean currents were captured in this scientific visualization created by NASA’s Goddard Space Flight Center in Greenbelt, Md.

“There is also a 20-minute long tour, which shows these global surface currents in more detail,” says Horace Mitchell, the lead of the visualization studio. “We also released a three-minute version on our NASA Visualization Explorer iPad app.”

Both the 20-minute and 3-minute versions are available in high definition here:http://svs.gsfc.nasa.gov/goto?3827

The visualization covers the period June 2005 to December 2007 and is based on a synthesis of a numerical model with observational data, created by a NASA project called Estimating the Circulation and Climate of the Ocean, or ECCO for short. ECCO is a joint project between the Massachusetts Institute of Technology and NASA’s Jet Propulsion Laboratory in Pasadena, Calif. ECCO uses advanced mathematical tools to combine observations with the MIT numerical ocean model to obtain realistic descriptions of how ocean circulation evolves over time. continue reading

cozydark:

Hubble Images Searchlight Beams from a Preplanetary Nebula |

The NASA/ESA Hubble Space Telescope has been at the cutting edge of research into what happens to stars like our sun at the ends of their lives. One stage that stars pass through as they run out of nuclear fuel is called the preplanetary or protoplanetary nebula stage. A new Hubble image of the Egg Nebula shows one of the best views to date of this brief but dramatic phase in a star’s life.

The preplanetary nebula phase is a short period in the cycle of stellar evolution, and has nothing to do with planets. Over a few thousand years, the hot remains of the aging star in the center of the nebula heat it up, excite the gas, and make it glow as a subsequent planetary nebula. The short lifespan of preplanetary nebulae means there are relatively few of them in existence at any one time. Moreover, they are very dim, requiring powerful telescopes to be seen. This combination of rarity and faintness means they were only discovered comparatively recently. The Egg Nebula, the first to be discovered, was first spotted less than 40 years ago, and many aspects of this class of object remain shrouded in mystery.

At the center of this image, and hidden in a thick cloud of dust, is the nebula’s central star. While we can’t see the star directly, four searchlight beams of light coming from it shine out through the nebula. It is thought that ring-shaped holes in the thick cocoon of dust, carved by jets coming from the star, let the beams of light emerge through the otherwise opaque cloud. The precise mechanism by which stellar jets produce these holes is not known for certain, but one possible explanation is that a binary star system, rather than a single star, exists at the center of the nebula. continue reading

cozydark:

Black Hole Caught Red-Handed in a Stellar Homicide |

Astronomers have gathered the most direct evidence yet of a supermassive black hole shredding a star that wandered too close. NASA’s Galaxy Evolution Explorer, a space-based observatory, and the Pan-STARRS1 telescope on the summit of Haleakala in Hawaii were among the first to help identify the stellar remains.

Supermassive black holes, weighing millions to billions times more than the Sun, lurk in the centers of most galaxies. These hefty monsters lay quietly until an unsuspecting victim, such as a star, wanders close enough to get ripped apart by their powerful gravitational clutches.

Astronomers have spotted these stellar homicides before, but this is the first time they can identify the victim. Using a slew of ground- and space-based telescopes, a team of astronomers led by Suvi Gezari of The Johns Hopkins University in Baltimore, Md., has identified the victim as a star rich in helium gas. The star resides in a galaxy 2.7 billion light-years away.

Her team’s results will appear in May 2 online edition of the journal Nature.

“When the star is ripped apart by the gravitational forces of the black hole, some part of the star’s remains falls into the black hole, while the rest is ejected at high speeds. We are seeing the glow from the stellar gas falling into the black hole over time. We’re also witnessing the spectral signature of the ejected gas, which we find to be mostly helium. It is like we are gathering evidence from a crime scene. Because there is very little hydrogen and mostly helium in the gas we detect, we know from the carnage that the slaughtered star had to have been the helium-rich core of a stripped star,” Gezari explained. continue reading

cozydark:

Astronaut Don Pettit on the International Space Station took this picture  during the annular/partial eclipse, looking back on Earth tocapture the shadow of the Moon.

cozydark:

Diverse Complex Networks Have Similar Skeletons |

Northwestern University researchers are the first to discover that very different complex networks — ranging from global air traffic to neural networks — share very similar backbones. By stripping each network down to its essential nodes and links, they found each network possesses a skeleton and these skeletons share common features, much like vertebrates do.

Mammals have evolved to look very different despite a common underlying structure (think of a human being and a bat), and now it appears real-world complex networks evolve in a similar way.

The researchers studied a variety of biological, technological and social networks and found that all these networks have evolved according to basic growth mechanisms. The findings could be particularly useful in understanding how something — a disease, a rumor or information — spreads across a network.

This surprising discovery — that networks all have skeletons and that they are similar — was published this week by the journal Nature Communications.

“Infectious diseases such as H₁N₁and SARS spread in a similar way, and it turns out the network’s skeleton played an important role in shaping the global spread,” said Dirk Brockmann, senior author of the paper. “Now, with this new understanding and by looking at the skeleton, we should be able to use this knowledge in the future to predict how a new outbreak might spread.” continue reading

(via talby:clement:bonerfication)

(via proofmathisbeautiful)

un:

By QuasimondoMario Klingemann

(via proofmathisbeautiful)

blua:

Cambridge University is putting the papers of Sir Isaac Newton online for the first time, including his own annotated copy of his greatest work, Principia Mathematica, with notes and calculations in his handwriting revising the book and answering critic 

(via proofmathisbeautiful)

g-f-p:

“Never Forever…” is a quantitative visualisation of the transient nature of empire. The visualisation graphs all known empires, colonies and territorial occupations from 2334 BCE to the present day.

more pictures here

(Source: a-science-blog, via proofmathisbeautiful)

2headedsnake:

crowquills.com

Andy Gilmore

(via proofmathisbeautiful)

(Source: mournfully, via proofmathisbeautiful)

implodesoncontact:

sunfoundation:

Olympic Evolution

This graph charts the participation of nations in the Summer Olympics since the beginning of the modern games in 1896. In the beginning, a mere 14 nations competed in the games. In 2008, the Olympics has grown to become a world culture phenomenon that now includes athletes competing under more than 200 different flags.

neato!

(via proofmathisbeautiful)

(via visual-poetry)

visual-poetry:

“self-portrait…” by micah lexier