ikenbot:

How to Build a Planet: Heavy Metals Are Key Ingredients

Image: An artist conception of a newly formed star surrounded by a swirling protoplanetary disk of dust and gas, where debris coalesces to create rocky ‘planetesimals’ that collide and grow to eventually form planets. A new study suggests small rocky planet may actually be widespread in our Milky Way galaxy. Credit: University of Copenhagen, Lars A. Buchhave

Planets may not be able to form without a heaping helping of heavy elements such as silicon, titanium and magnesium, a new study suggests.

Stars that host planets have higher concentrations of such “metals” — astronomer-speak for elements heavier than hydrogen and helium — compared to iron than do planetless stars, the study found.

“To form planets, one needs heavy elements,” said lead author Vardan Adibekyan, of the Centre for Astrophysics of the University of Porto in Portugal.

Connected at birth

Planets coalesce from the disk of dust and gas left over after the birth of their parent star. According to the leading theory of planet formation, the core accretion model, small particles clump together, growing larger and larger until they produce protoplanets.

Scientists have long suspected that stars with higher metallicities are more likely to have planets orbiting them. Iron has long been a primary indicator.

“Usually, in stellar physics, people use the iron content as a proxy of overall metallicity,”

Full Article

Look a little gross? That’s because this lump is not only a brain, but one that is almost 2,700 years old. It was preserved after its home skull was dropped into an oxygen deprived pit of water, probably the result of its owner being hanged and then decapitated.

Scientists described it as “odorless…with a resilient, tofu-like texture.” Yum!

discoverynews:

how did we find out our galaxy is a spiral? It’s not like we flew out there and took a look. Grab a cup and find out…

Seeing the Milky Way Spiral in a Coffee Cup

The fact that we know it resembles the Milky Way is pretty clever given that no one has ever come remotely close to getting such a stunning view of the galaxy we live in. It’s a testament to human logic that has granted us the knowledge of the shape of our galaxy and it’s a story that starts back at the beginning of civilization.

Back when our ancestors, the view would have been stunning with the ghostly glow of thousands of visible stars arching overhead…

coffee is a funny thing…

I always forget that for most of history, the Milky Way was visible across our sky just about anywhere in the world. With an inspiration like that, it’s not hard to see how so many religions popped up.

War Sand

jtotheizzoe:

As much as 4% of sand on Normandy’s beach is made up of miniscule fragments of steel, the remnants of shrapnel from WWII’s D-Day. It’s a story that’s part geologic wonder, and part reminder of what will be left of our civilization when we’re gone. More at BLDGBLOG.

4% of a beach is still a LOT of steel. To be fair to steel’s durability, the coast is a pretty rough place to hang out. All that sand came from shells and rock, which didn’t disintegrate by itself.

jtotheizzoe:

‘Earliest’ evidence of modern human culture found

How far back do you think human culture goes? You know, the sharing of creative ideas like tools and creation?

Decades of study on some basic tools pulled from a cave in South Africa have finally determined that traces of modern human culture surfaced as far back as 44,000 years ago. That’s more than double the last estimates!

The San hunter-gatherers of South Africa (one pictured above) still use basic bone, wood and stone tools. Artifacts found in this South African cave are so close to the tools used today that there’s no doubt that 44,000 years ago, a cultured clan was making and using them regularly. They even mastered organic poisons taken from castor beans to tip their spears with.

This is a very cool find, and adds some detail to the timeline of human evolution. Considering that our modern anatomy only showed up ~150,000 years ago, it’s exciting to discover that shared tool creation and culture weren’t that far behind. 

So let’s all try to act a little cultured today in their honor, shall we??

(via BBC News)

quantumaniac:

Happy Birthday NASA! 

Today, July 29th, marks the 54th anniversary of the passage of the National Aeronautics and Space Act – which established NASA. Since February 2006, NASA’s mission statement has been to ”pioneer the future in space exploration, scientific discovery and aeronautics research.” NASA replaced its predecessor, the National Advisory Committee for Aeronautics (NACA). The agency became operational on October 1, 1958.

The Trinity Test, .025 seconds after detonation. 

July 16, 1945

“For I am become Death, Destroyer of Worlds.” – J. Oppenheimer

Earliest Americans Arrived in 3 Waves, Not 1, DNA Study Finds

Link: Earliest Americans Arrived in 3 Waves, Not 1, DNA Study Finds

canisfamiliaris:

Most scientists have long asserted that the Americas were peopled in one large migration from Siberia that happened about 15,000 years ago, but new full-genome research shows that this central episode was followed by at least two smaller migrations from Siberia, one by people who became the ancestors of today’s Eskimos and Aleutians and another by people speaking Na-Dene, whose descendants (Apache, Navajo, Chipewyan, and others) are confined to North America. The research, which confirms linguist Joseph Greenberg’s rejected 1987 hypothesis, was published online on Wednesday in the journal Nature.

jtotheizzoe:

History, Chemistry, and Cold Beer

How a Mesopotamian mix-up led to 8,000 years of cold suds. Ancient civilizations in the Middle East made a bread out of malted barley. When that bread got mixed with water, met some airborne yeast and was left to sit in the dark, the bakers fell over when they tried to drink it.

That’s how the legend goes anyway. Beer and other fermented drinks have been behind our transition from hunter-gatherers to agriculture, many advances in early chemistry and even how we organized early American towns.

Since all graduate student paths lead to beer, it’s high time we scientists get to know our best friend’s origins.

(via Inside Science)

History, chemistry, and beer. Such quality!

explore-blog:

A Purple Martin (Progne Purpurea), from America’s Other Audubon – the fascinating story of how one young Victorian woman by name of Gennie Jones changed the face of science illustration through art, science, and entrepreneurship.