DARK MATTER FILAMENTS LINK GALAXIES INTO A COSMIC WEB

Scientists still don't know what dark matter is, although there appears to be five times more of it than of normal, visible matter, and cosmologists believe that it has played a crucial role in the evolution of the universe.

Since it doesn't interact with light or other electromagnetic radiation, and barely if at all with normal matter except through gravity, it's not surprising that it's proven excruciatingly hard to detect. A long series of increasingly sensitive experiments have narrowed the range of possible targets, but so far have failed to find actual dark matter particles.

Now, researchers at the University of Waterloo, in Ontario, Canada, have confirmed one of the key predictions of how dark matter should act by imaging for the first time strands or bridges of dark matter linking neighboring galaxies.

Dark matter filaments bridge the space between galaxies in this false colour map. The locations of bright galaxies are shown by the white regions and the presence of a dark matter filament bridging the galaxies is shown in red. Credit: S. Epps & M. Hudson / University of Waterloo

Astronomer Michael Hudson and graduate student Seth Epps detected the dark matter bridges through the gravitational lensing effect they had on the light coming from even-more-distant galaxies. The image above combines the observations of 23,000 galaxy pairs, which allowed the researchers to detect the dark matter filaments with a high degree of statistical certainty.

“For decades, researchers have been predicting the existence of dark-matter filaments between galaxies that act like a web-like superstructure connecting galaxies together,” said Hudson. “This image moves us beyond predictions to something we can see and measure.”

Their work proves the prediction that rather than isolated "island universes," galaxies and even larger galaxy clusters are like beads of condensation on an invisible cosmic web of dark matter.

Beads of water on a spider's web

https://goo.gl/images/RJO6Xe

You can find the original paper here.

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Time for a New National Holiday -- Creation Day!


With Rick Perry's Day of Prayer and endorsement of the teaching of creationism in Texas schools, Michele Bachmann's links to Dominionism, and the Republican presidential candidates' near-universal rejection of climate science (what's with Mitt Romney and Jon Huntsman?), we thought it was time to pass on this timely proposal from The Committee for Creation Day:

August 23, 2011

The Committee for Creation Day

Washington, DC

“Creation Day: An Idea Whose Time Has Come”

Dear Senators

BARRASSO, BROWNBACK, CHAMBLISS, COBURN, CORNYN, CRAPO, DEMINT, HATCH, MCCAIN, RISCH, SESSIONS & THUNE

and Representatives
AKIN, ALEXANDER, AUSTRIA, BACHMANN, BISHOP, BLACKBURN, BLUNT, BOEHNER [and others]


and presidential candidates
BACHMANN, PERRY [and others],


First, we at The Committee for Creation Day want to congratulate those of you who have earned a Defenders of Liberty rating from the American Conservative Union. Your 100 percent advocacy of conservative values represents a remarkable intellectual, moral and political achievement, and is greatly appreciated.

Given your proven support for Christian values, we want to bring to your attention a proposal that we believe can help unify all right-thinking citizens behind God’s plan for the United States—Creation Day, a new national holiday.

As you know, in 1654 the great scholar Archbishop James Ussher calculated that God initiated Creation during the night preceding Sunday, October 23, 4004 B.C.

What could be more important than officially recognizing that awesome moment, especially during these crucial and difficult times?

--Making Creation Day a national holiday would provide further proof that the United States is a nation founded on Christian principles and relying on God’s grace and guidance for its success.

--Federal recognition of Creation Day would provide invaluable support for the state-by-state, school-board- by-school-board battle to provide public school students with a balanced understanding of the scientific theory of intelligent design versus godless evolution, and balanced access to the truth about Creation compared to scientific theories claiming that the universe is billions of years old.

--Official establishment of Creation Day would bring some much-needed joy into these difficult years of economic crises, droughts, floods and other catastrophes that herald the End of Days. Environmentalists have their Earth Day. Why shouldn’t the rest of us have the right to unite in celebration of the Universe’s Birthday?

We understand that there may be some technical problems with the date of October 23. It falls right between Columbus Day, October 10, and Veterans Day, November 11. Some might think that having three Federal holidays in a month would be excessive. However, given the current insolvency of the government, not to mention our shared desire to cut government down to its lowest possible level, the more time Federal employees have off the better. We’re sure that, like the FAA employees who continued to work without pay during the recent debt ceiling crisis, other Federal employees will be happy to be furloughed without pay should October 23 fall on a weekday. Or perhaps Columbus Day and/or Veterans Day could be moved to some other dates, for example to March and April, which lack Federal holidays, or simply cancelled. After all, the discovery of America and even recognition of our brave veterans pale in importance to officially recognizing the Day It All Began.

We feel that it is worth noting that if making Creation Day a national holiday could be accomplished this year, then the very first celebration would fall on Tuesday, October 23, 2012. That's exactly two weeks before the general election. Enough said.

We think that we can accurately note that we represent tens of millions of voters, not to mention potential donors who are in a position to support Godly politicians generously, who would appreciate and applaud your advocacy for, and, God willing, creation of this new and vitally important national holiday.

Help us Ussher in a new, God-fearing era in America.

Sincerely,


The Committee for Creation Day


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New addition to the human family tree

Two-million-year-old “mother and child” fossils found in South Africa

Fossilized bones representing a new species of likely human ancestors were described today in the journal Science.

The remarkably well preserved fossils were of an adult female and a pre-adolescent male who shared a unique checkerboard mixture of apelike and human features. They were discovered in August, 2008 in a remote site in South Africa by a team led by Lee Berger at the University of Witwatersrand.

Remarkably, the fossils were first spotted by Berger’s son Matthew. “It was a child, found by a child,” says Berger. The Government of South Africa and the University of Witwatersrand are sponsoring a contest among South African children to name the child.

Berger, the study’s lead author, stopped short of saying that the pair were in fact a mother and her child, but said that his team will be using a variety of techniques to try to answer that question. “They were almost certainly part of the same troop,” he says. “So there’s a very high probability that they are related to each other.”

Geologist Paul Dirks, part of the group that studied the fossils and the setting in which they were found, thinks that the two died together, probably in a major flood or mudslide that washed their bodies down into the depths of a cave, where their remains were safe from scavengers and rapidly turned into fossils.

Berger and his colleagues spent the past year and a half studying the fossils of these two individuals, along with the bones of hundreds of animals found near them, and the geological layers above and below them.

This allowed them to pin down the time when these creatures lived extremely accurately. “Our ability to date these sites in southern and eastern Africa has become more and more precise,” says Berger. They almost certainly lived 1.95 million years ago, give or take a few thousand years.

These are not the oldest probable human ancestors. For example, two members of the species Australopithecus afarensis left a trail of surprisingly human-like footprints in a bed of volcanic ash in Laetoli, Kenya 3.6 million years ago, and the tool-using Homo habilis lived some 2.5 million years ago.

However, the new species, which Berger and his colleagues have named Australopithecus sediba, presents a surprising mix of ancient and more modern traits, as if a snapshot had caught the species in the awkward process of morphing from ancient apelike predecessors to more recognizably human ancestors.

“Australopithecus sediba is undoubtedly a highly transitional species, with a mosaic of characteristics shared with later hominids but with other features typical of the australopithecines,” says Berger.  Hominids include humans and their direct ancestors or very close relatives, while the australopithecines were earlier small-brained but bipedal species, one of which is thought to have evolved into the first bigger brained, walking and tool using human species.

Berger believes that Australopithecus sediba is either a direct ancestor of one of the earliest members of our genus, Homo, or a very closely related side branch.

The new species studied by Berger and his colleagues had long legs and human-like hips, so they could walk easily. At the same time, they had very long arms and short, but very strong hands and fingers that meant that they were still at home in the trees. “They were very competent walking bipeds,” says Berger, “but with these backup, parachute arms that allowed them to climb trees.”

Even their skulls show a peculiar mixture of features. Their brains were small, around 420 cubic centimeters—less than one third of the volume of modern human brains. However, their faces had many human-like features, including a well-developed nose, well defined cheeks and a sloping but somewhat bulging forehead.

“They would look dramatically different [than other ancient human ancestors]” says Berger. “They would have long, apelike arms but with short, powerful, human-like hands. They would have human shaped hips and long legs, and a modern-like face, but with a very small head.”

A. sediba  skull
photo by Brett Eloff, courtesy Lee Berger, Univ. of Witwatersrand

Berger is also intrigued by the fact that the adult female was nearly as tall as the predicted full height of the male. This similarity in size between males and females might be associated with human-like families and groups, in contrast to the extreme male-female size differences found in primates such as gorillas with a single dominant male guarding and dominating a harem of females.

“Sediba has taken a leap toward a social structure where you don’t have a dominant alpha male and you are lowering competition between males, who live together with females and their offspring in a social group,” Berger says.

He compares this new species with its odd mix of ancient and modern features to the Rosetta Stone that first let scholars make sense of Egyptian hieroglyphics. “These are a remarkable sample of fossils,” says Berger. “They’re going to answer a great many questions about human evolution during the period from 2 million to 1.7 million years ago, a period that is very poorly represented in the fossil record.”

Even if long-legged but small-brained Australopithecus sediba didn’t quite make it into the genus Homo, I for one am happy to welcome them to our ancestral family tree.

Robert Adler

for the institute

accutane lawsuit

"Humans have always walked this way because that is the way we were 'designed'"

I recently wrote an online news story for New Scientist about 1.5-million-year-old footprints discovered in Kenya. I found some of the readers' comments disturbing. It took me a while to figure out why.

The research article appeared in Science on February 27, 2009. It described the discovery and study by an international team of researchers of the second oldest footprints left by human ancestors--the oldest showing unambiguous evidence of modern foot anatomy and our efficient way of walking.

Although bipedalism dates back several million years earlier, the footprints reveal that our ancestors--from foot size and shape almost certainly early Homo erectus--had evolved anatomically modern feet and a springy stride like ours by 1.5 million years ago.

At first I was pleased to see that the story generated lots of comments. It's good to know that people are reading what one writes.

The first few comments were fine, but I was unpleasantly surprised to find that the conversation quickly devolved into an exchange between creationists and supporters of evolution.

I had several reactions. The first was irritation, like finding that an uninvited guest has crashed your party. The second was frustration, even anger, at the creationists' glib dismissal of the dozen scientists who had discovered, painstakingly excavated, and carefully analyzed the footprints, not to mention a century or more of physics, geology, paleontology and, of course, evolution.

Everything was fair game, from the identification of the footprints--"The look like gorilla prints to me,"--to the dating--"1.5 million years ago? Was someone there to make a record of the date?"--to the theory of evolution as a whole--"None of which is supported by any evidence except what men decide to believe."

It was obvious that when any mere field of science got in the way of creationism, the science had to be trashed.

In the end, however, I realized that my strongest feeling was boredom. When I tried to read the creationists' comments, my attention wandered, my eyes glazed over, and I wanted to be doing anything other that trying to make sense of comments like "All features of a species have an ability to adapt to an environment . . . but that is a far cry from turning a fish into a bird."

Creationism, I realized, is God-awful boring.

Creationsim collapses the vast grandeur of the cosmos into a morality play about--you guessed it--us.

Not counting old-Earth creationists, who accept a geological time scale but still reject evolution, creationists pancake the universe's nearly 14 billion year history into a few thousand years.

Here on earth, creationists replace the chaotic creativity of more than four billion years of geological, chemical, and biological churning with six days of check-list Creation.

In the end, creationism answers every question about how we and everything we find around us got that way with, "God (excuse me, the Intelligent Designer) made it that way."

How did those footprints end up buried under layer after layer of distinct, datable sediments? God put them there.

What does it mean that, suitably measured, the ratio of argon-40 to argon-39 in the volcanic ash above the footprints is a tad lower than in the ash below them? Could it mean that the lower layer is a few hundred thousand years older? Nope. God salted those isotopes in just that way.

What can we learn by comparing these footprints to the 3.7-million-year-old Laetoli prints? Could their differences shed light on the evolution of our feet and walking style? Nah. God made the Laetoli prints smaller, wider and flatter, and these new prints longer, slimmer and more arched. Don't ask why.

What's the relationship between the increased mobility of Homo erectus that these prints confirm and the fact that it became the first hominin to leave Africa and thrive across Europe and Asia? Hmm. Must have something to do with the expulsion of Adam and Eve from Eden. Check out Genesis 1:26 through 3:24 for the details.

It's not that an omnipotent Intelligent Designer isn't a good-enough answer to such questions, it's that it is way to good an answer. It's a game ending, that's-all-she-wrote, one-size-fits-all, alpha-to-omega, end-of-story, let's-all-go-gome, hydrogen bomb answer.

By answering everything, it answers nothing.

I obvioiusly don't understand the need for capital-C Certaintly and capital-T Truth that creationists seem to share. 

I'm much more curious about what the next dig will turn up, how the next fossil or footprint of flower-strewn burial will change our understanding of our past, what a more detailed understanding of the changing geology and climate of east Africa two or three million years ago will tell us about the challenges our ancestors faced and why some of them survived and reproduced (and yes, evolved), while others faded away.

I know that I'll never get Certainty or Truth from science. What excites me is what science gives us every day--new and better answers to old questions, and answers that provoke new and better questions.

God may be The Answer, as the bumper stickers and billboards tell me. Perhaps to some people and some questions, but just not to the questions that science and scientists ask.

Robert Adler

for the institute