Cosmic Conundrum Hits Close to Home

By the time cosmic rays hit Earth, they have journeyed through so many magnetic fields and other perturbations that they arrive nearly uniformly from all directions.
So when a detector in New Mexico began registering streams of charged particles coming from the general direction of the Orion nebula and about 500 light-years from Earth -- a neighbor by astronomical measures -- scientists took note.
"I can't tell you what it is, but I can tell you what it isn't," said University of Maryland physicist Jordan Goodman, "It isn't a statistical fluctuation in our data. It's not an error."
Scientists aren't sure what causes cosmic rays, which are charged particles, namely protons and electrons, moving at high speeds due to unknown events. The list of candidates includes supernova explosions and quasars.A local source of cosmic rays is one explanation for the finding made by Goodman and his colleagues, though what that could be is pure conjecture.
Another theory is that the rays originate from afar, but are being funneled toward Earth due to a magnetic field from an object such as Geminga, a relatively young pulsating star that is surrounded by clouds of molecular gas. Geminga radiates brilliantly in high-energy gamma rays.
"If Geminga is the source, it isn't clear that we would see it," Goodman said. "The magnetic fields would have to be aligned in some way" relative to Earth.
The finding was the second in less than a month that uncovered unusual evidence of cosmic rays.
Scientists using a detector on a balloon-borne experiment above Antarctica found more cosmic ray electrons than expected and suggested dark matter may be responsible, since the energy signals match what physicists believe would result when dark matter is annihilated."It is certainly possible that known astrophysical objects, such as nearby supernova remnants, spinning pulsars or, possibly, microquasars are responsible," said Yousaf Butt, with the Harvard-Smithsonian Center for Astrophysics.
Goodman and his colleagues made their discovery with the Milagro Gamma Ray Observatory, which is located in a covered pond, about the size of a football field, in the Jemez Mountains near Los Alamos, N.M.
The observatory detects highly energized particles striking the atmosphere by measuring the cascading effects on secondary particles that make it to the planet's surface.
Since the study began more than seven years ago, Milagro -- Spanish for "miracle" -- has detected more than 300 billion hits. Goodman's work was published last month in Physical Review Letters.

Shark "Virgin Birth" Confirmed

A female blacktip shark in Virginia fertilized her own egg without mating with a male shark, new DNA evidence shows.

This is the second time scientists have used DNA testing to verify shark parthenogenesis—the process that allows females of some species to produce offspring without sperm.
The female shark, dubbed Tidbit, died during a routine physical exam before the pregnancy was identified.

A necropsy—an animal autopsy—after her death revealed she was carrying a near-term pup fetus that was about 12 inches (30 centimeters) in length.

Tidbit was caught in the wild when she was very young and reached sexual maturity in a tank at the Virginia Aquarium in Virginia Beach, where she lived for eight years.

"The interesting thing about that was there were no male blacktip sharks in the tank for the entire time of her captivity," said Demian Chapman, a researcher with the Institute for Ocean Conservation Science at Stony Brook University in New York.

"So the question is, where does this baby come from?" he asked.

Chapman is the lead author of a study on the female blacktip in the latest issue of the Journal of Fish Biology.

DNA fingerprinting

Chapman and his colleagues generated a DNA fingerprint for the mother shark and her pup fetus with a procedure identical to a human paternity test.

Ordinarily, a shark's DNA contains some genetic material from its mother and some from its father. Tidbit's pup, however, was not ordinary.

"Every part of the fingerprint of the embryo comes from the mother," Chapman said. "In other words, there is no genetic material from a father."
"Virgin Births"

All non-mammal vertebrate species are theoretically capable of parthenogenesis, scientists say. Examples have been documented in komodo dragons (read story), pythons, rattlesnakes, chickens, and turkeys.
Parthenogenesis is not possible in humans because if all the genetic material comes from the mother, certain genes will be switched off, and the embryo won't develop.

"For sharks in captivity, [parthenogenesis] has probably occurred more times than has been documented," says Robert Hueter, director of the Center for Shark Research at Mote Marine Laboratory in Sarasota, Florida.

The question then becomes, is parthenogenesis a type of developmental anomaly or a response to the female shark not having a mate in captivity?

"The fact that only one shark embryo was formed may suggest that this is more a case of an egg developmental aberration rather than a physiological response to the lack of a mate," said Hueter, who was not involved with the study.

No Variation

Normally, an embryo is formed when an egg containing half its chromosomes is fertilized by a sperm containing the other half.

When an egg cell is formed, a plant or female animal also produces three other cells called polar bodies. In the type of parthenogenesis observed in sharks, one of those cells behaves like a sperm and fertilizes the egg.

"But that cell is genetically identical to the egg," Chapman said. "So that's where you lose a lot of genetic variation."

Offspring produced by parthenogenesis are not exact clones of their mothers, however, because the genetic material is mixed differently.

Still, researchers believe the risk of congenital defects increases in animals whose DNA lack genetic variation.

"There's an increased risk of having a weakened immune system and there's a risk of reproductive abnormalities," Chapman said. "But in some cases, they'll be able to survive."

The scientists have not ruled out the possibility that increased stress from the abnormal pregnancy contributed to Tidbit's death.

Space Wakeup Songs

Space shuttle crews in orbit probably don't need a prod from Mission Control to get going in the morning, but the wake-up song has become a NASA tradition.
Astronauts' families and friends often make suggestions for tunes and occasionally provide the music. Sometimes the wake-up song is very personal, such as the serenade of teacher-astronaut Barbara Morgan by her singer-songwriter son Adam. Often, it's the mission itself that provides the inspiration.
Here's a look at Discovery Space's favorites:
10. Mission: Impossible
Not taking any chances, Mission Control waited until the Hubble Space Telescope servicing crew of 2002 had completed most of its work before piping in the "Mission: Impossible" theme song to get things moving on flight day eight.
Recording: WAV - Net Show - RealAudio
9. Rocky
It was a moment of triumph when Kathryn Sullivan floated outside the airlock of space shuttle Challenger in October 1984 to become the first American woman to walk in space. Her crewmates included Sally Ride, NASA's first female astronaut. NASA marked the mission by playing the theme song from "Rocky."
8. Free Bird
Two Russians joined the crew of space shuttle Atlantis in September 2000 to get the newborn International Space Station ready for its first long-duration residents. After 10 days at the outpost, the astronauts were ready to come home. Wakeup music the day they departed -- Lynyrd Skynyrd's "Free Bird."
Recording: WAV - Net Show - RealAudio
7. Godzilla Vs. Space Godzilla
NASA wasn't anticipating any trouble when it woke the crew of shuttle Endeavour with the battle scene song from the movie "Godzilla Vs. Space Godzilla," then followed up with few bars of Blue Oyster Cult's "Godzilla." Astronaut Al Drew wrapped up by wishing Japanese astronaut Takao Doi good morning -- in Japanese.
Recording: MP3 - WAV
6. Pigs in Space
Joe Engle and Richard Truly had to end the second mission of the space shuttle program three days early when a generator failed. But the men worked through the night to complete a series of tests on the shuttle's new robot arm. They enjoyed a bit of comic relief with skits from The Muppets' "Pigs in Space."5. Attack of the Killer Tomatoes
NASA's Long Duration Exposure Facility (LDEF) was supposed to spend a year in orbit for tests of how various materials weathered the harsh space environment. But because of the Challenger accident, five years passed before LDEF came back to Earth. NASA didn't know what to expect from the experiments, which included 12.5 million tomato seeds. With tongue in check, Mission Control roused the LDEF retrieval crew with "Attack of the Killer Tomatoes."
4. Do You Want to Know a Secret?
After shuttle Atlantis lifted off in December 1988, NASA imposed a news blackout to keep details of its Department of Defense mission classified. Word leaked out about a special wake-up recording produced by a Houston radio station. With background music from the "Star Wars" theme song, the voice of Darth Vader greeted the crew. Satirical lyrics from The Beatles' "Do You Want to Know a Secret?" followed. Pentagon officials were not amused.
3. Monster Mash
Flight controllers opted for a bit of Halloween humor when it woke the crew of STS-58 with "Monster Mash," by Bobby "Boris" Pickett. Instead of goblins and bats, the shuttle had rats -- 48 of them (all caged, of course) -- for a series of life science experiments.
2. Woody Woodpecker
NASA delayed launching the STS-70 mission after discovering woodpeckers had drilled holes in insulation covering the space shuttle's fuel tank. During repairs, Woody Woodpecker was added to the crew patch as an ex-officio member of the crew. The first wakeup song of the mission was a homage to Woody, of course: the theme from Woody Woodpecker TV show.
1. We've Only Just Begun
The Apollo 17 astronauts left the moon in 1972 not knowing if or when people would be back. Among their wake-up tunes: The Carpenters' "We've Only Just Begun."

16 Days in Space and ??? To Get Home

Ten days after a detoured landing in California, the space shuttle Endeavour has begun a cross-country piggyback ride on top of a modified jumbo jet enroute to Florida.It’s not an easy journey. The 100-ton spaceship makes for one burly passenger, vulnerable to high winds, rain and other rather typical atmospheric phenomena, particularly during winter. It took two days just for the weather to be good enough to begin the journey.

The shuttle and its entourage made it as far as Fort Worth, Texas, last night. NASA says the chance the ferry flight would arrive at the Kennedy Space Center in Florida today are pretty slim, given an advancing cold front.

NASA is not as eager to talk about why the shuttle landed in California in the first place. Typically, flight directors will keep the orbiter in space an extra day if conditions in Florida preclude a touchdown on the scheduled landing day. Florida weather is notoriously fickle, sometimes difficult to predict an hour in advance, let alone a day.

So NASA’s call to divert Endeavour to California raised a few eyebrows, at least in Florida. It’s not really the money, though the $1.8 million it costs for the relocation would cover more than a few scholarships and salaries. It’s more about the time it takes to make the flight and the risks to the ship during the journey.

“It kind of struck us as a little unusual,” said George Diller, whose days as a NASA public affairs officer date back longer than my 21 years as a reporter covering the program. “Usually they wait at least one day before they make a call to come down there.”

“They” is the good folks at the Johnson Space Center in Houston, who runs the show from the time the shuttle clears the top of the launch tower to wheels stop on the runway.

I got curious about how the weather actually turned out on Dec. 1, the day the shuttle likely would have landed if a 24-hour delay had been ordered.

Apparently, I wasn’t the only one, because Bill Johnson, the news chief at KSC, had the report on the ready: North to northwest winds up to 10 knots. Visibility: Unlimited. In other words, a good day for landing.

The response from JSC was not so warm. “Wow, you’re the weather forecaster now,” sneered one public affairs officer whom I’ll not name on the condition that he promise to refrain from using sarcasm in the future when responding to uncomfortable questions like, “Why didn’t NASA wait a day to see if the weather in Florida got better?”

He also told me predictions from the Spaceflight Meteorology Group were that crosswinds at the Florida runway were “on the edge” (the limit is 15 knots.)

KSC folks weren’t buying that. “All you had to do was watch any local TV station and they were all predicting it was going to be a nice day,” said another press officer whom I’ll not name because I like him and I don’t want him to get in trouble for speaking his mind to a reporter.

Bottom line appears to be that NASA could have landed in Florida on Dec. 1. Now, that’s not to say that there wasn’t some OTHER more compelling reason to bring Endeavour back to Earth on the first best opportunity, such as maybe those fine folks flying in space were ready to get home.

That’s OK by me and I’ll happily fork over my share of the $1.8 million ferry flight tab. Heck, this is the agency that sent astronauts to the moon, for god’s sake. Surely, they know best about when -- and how best -- to bring our spacebirds home. I’m just one of those people who like to know what I’m paying for.

Number of Eggs in a Nest Depends on Climate

Some birds lay one egg while others lay up to 50 or more, and now researchers have figured out why, to the point where they can accurately predict egg counts for virtually all bird species.
Their forecasting might seem like an egg conjuring trick, but the secret comes down to predictors, such as the type of nest the bird builds and how close each avian species is to the poles.
Tropical birds, as it turns out, have a more laid-back approach, with generally fewer eggs within each clutch.
"You'd think it would be just the opposite, as the hypothesis for years was that the large amount of resources in the tropics would lead to more egg laying productivity, but we determined that wasn't the case," lead author Walter Jetz told Discovery News.
"Seasonality is far more important than the absolute amount of resources," added Jetz, an associate professor of biology at the University of California at San Diego.He explained that the closer birds are to the poles, the more extreme seasons they experience. Species in these locations often have higher mortality rates. It's therefore to their advantage to lay more eggs when they can, before it's too late.
Defined seasons also lead to peak periods of food and habitat availability, such as during spring. Suddenly birds find themselves with "huge amounts of resources, so they capitalize on them much more than at the tropics, where no such peaks exist," Jetz said.
For the study, he and his colleagues compiled information on clutch size, avian body mass, migratory behavior, nest type, bird diet, latitude, temperature and more. The scientists observed patterns in the numbers of eggs birds laid, allowing them to create a model that predicts variations in clutch sizes both on global and more localized levels.
The findings are published in the latest PLoS Biology.
In addition to seasonality, whether or not a bird lays its eggs in a protective cavity or just out in the open helps to predict its number of eggs.
"The hypothesis is that cavities are better protected, so woodpeckers, chickadees and other cavity nesters are less likely to be raided, so they tend to invest more in egg laying," Jetz said.

"Ground nesters, on the other hand, shouldn't put all of their eggs in one basket," he added, since predators are then more likely to find themselves with a free and easy egg dinner.

It would seem logical that all birds would hide their eggs in protective cavities, but he explained that, "not all the world is covered with trees." Birds in the desert, for example, often have no choice but to lay their eggs more in the open. Cavity nesting also is an ability that only a select group of birds evolved.

The scientists additionally determined that migrating birds tend to lay more eggs. Birds within certain families also tend to share similar clutch sizes. Big, flightless birds, for example, may often have large clutches containing anywhere from 10 to 74 eggs.

Robert Ricklefs, a professor of biology at University of Missouri at St. Louis, told Discovery News that, "Dr. Jetz's study is notable for its comprehensiveness and the excellent analytical applications."
Ricklefs added that he was "especially gratified to see that seasonality of temperature, migration, and nest type play the dominant roles, as these factors have been particularly prominent in the literature."
Given the importance of climate to birds, the global egg count, and consequently avian populations worldwide, may be in jeopardy due to climate change.
It has the potential of not only harming a "bird's way of life, but also its where of life," Jetz said, referring to how many species may be forced to shift their geographical ranges.
In the future, the new clutch size prediction model could help conservationists and other avian experts to better understand bird egg laying patterns in what Jetz and his colleagues call "a world of change."

Fifth of World's Corals Dead

Almost a fifth of the planet's coral reefs have died and carbon emissions are largely to blame, according to an NGO study released Wednesday.
The report, released by the Global Coral Reef Monitoring Network, warned that on current trends, growing levels of greenhouse gases will destroy many of the remaining reefs over the next 20 to 40 years.
"If nothing is done to substantially cut emissions, we could effectively lose coral reefs as we know them, with major coral extinctions," said Clive Wilkinson, the organization's coordinator.
The paper was issued on the sidelines of the December negotiations on a new global treaty on climate change, taking place under the U.N. flag.Half a billion people around the world depend on coral reefs for food and tourism, according to a common estimate.
Experts say the coral die-off has several causes, including local pollution, overfishing and invasive species.
But, they say, rising ocean temperatures caused by the greenhouse effect, and acidification, caused by the ocean's absorption of carbon dioxide from the atmosphere, are probably the biggest triggers.
"If nothing changes, we are looking at a doubling of atmospheric carbon dioxide in less than 50 years," said Carl Gustaf Lundin, head of the the global marine program at the International Union for the Conservation of Nature, an umbrella network for more than a 1,000 NGOs and government groups.
"As this carbon is absorbed, the oceans will become more acidic, which is seriously damaging a wide range of marine life from corals to plankton communities and from lobsters to seagrasses."
Nearly half of global coral reefs are still healthy, but the overall downward trend shows no sign of stopping, the study found. It added, though, that the damage could be braked by strong conservation measures, such as properly policed marine parks.

Commentary: "Hell on Earth" in Zimbabwe

Author Alexandra Fuller grew up in Zimbabwe, Malawi, and Zambia, where her family still lives. She now resides in Wyoming with her husband and three children. Fuller is the author of three works of non-fiction, including the memoir Don't Let's Go to the Dogs Tonight: An African Childhood. On the 60th anniversary of the United Nations' Declaration of Universal Human Rights, she reflects on the disease devastating her former home of Zimbabwe.

If it was President Robert Mugabe's intention to organize hell on Earth, he has succeeded. It's December in Zimbabwe, and that means the rains are frequent and the sun is at its hottest. The harvest—predicted to be ridiculously inadequate—is half a year away. Electricity is sporadic. No garbage has been collected for months. There has been no running water in many cities for days. Zimbabwe is a steam-bath of infection. Cholera, that most medieval of diseases, and the ultimate indication of a state that has failed her people, is rampant. Violence spills over. I follow every new development because those are my people, in that hell.Zimbabweans are not strangers to violence and terror. We once fought a bloody civil war to decide who would control the land. Brother turned on brother. We all lost someone in those years, and many of us learned to live with death; it was the background noise to our lives. Villages were razed to the ground. Yes, there were atrocities.

It was war, but it wasn't hell.

People risked death, endured heartbreak, rather than turn their backs on the country. Always, there was an understanding that the land was worth the fight. And in the end, when peace came, Mugabe himself put it best: "To us the time has come for those who fought each other as enemies to accept the reality of a new situation by accepting each other as allies."

Most Zimbabweans settled down and did just that, brought together by a common loyalty to the earth beneath their feet. But in the last few years, with Mugabe and his crazed henchmen in control of a diabolically orchestrated free-fall, an estimated four million people have fled their country. Above all, Zimbabweans are lovers of their land. No, that does not go far enough—they are their land. For many Zimbabweans the blur between soul and land begins in this way: They are born, and then the umbilical cord is taken straight from the mother and planted in the earth, so that it can take root and grow.

Pulling away from that ground causes some kind of death, a suffocation of exile. Deprive Zimbabweans of their land, and you deprive them of air, water, food.

And now that land has become a madman's torture chamber.

What makes this horror something we will all have to live with one day is that we can hear the cries from Zimbabwe, and from her borders, and yet we do nothing. News reports and desperate letters from inside the country have been circulating around the Internet for months. In tone and in content they sound eerily similar to the letters and warnings we have heard from other hells on Earth: Darfur; Bosnia; Cambodia; Nazi Germany; Rwanda—before that awful April in 1994.

In October, Hans-Gert Pöttering, President of the European Parliament, issued this unequivocal warning: "If we do not act, we will have the lives of hundreds of thousands if not millions of people on our conscience. Did we not commit that Rwanda/Burundi must never happen again? However, this is exactly the situation the average Zimbabwean is experiencing right now."

There will be an end to the crisis in Zimbabwe one day. Then we will count that country's disappeared, her diseased, her displaced, her dead. We will ask, "How did this happen?"

But we already know how it happened. It happened because we stood by.