Flu season is underway in the United States, and a new report shows that flu activity is already higher than typical for this time of year. The new CDC report, published Dec. 7, also said that during the week of Thanksgiving, the percentage of people visiting the doctor for flu-like illness was 2.3 percent, which is slightly above the "national baseline" for flu visits — the threshold for what's typically seen in the off-season — which is 2.2 percent. "Influenza activity in the United States … has been increasing since early November," the researchers wrote in their report.
Mankind hasn't had to deal with much in the way of deadly meteors over the years, but on the few occasions when one of the pesky space rocks does target Earth, they often self-destruct in the air before it even reaches the ground. For years, researchers have puzzled over why that happens, but a new study published in the Meteoritics & Planetary Science suggests the first concrete explanation.
Using a recent meteor explosion event — the rock that detonated in the sky above Chelyabinsk, Russia — as an example, scientists attempted to explain why the massive object seemed to cut its life short before striking ground. Using computer simulations to model the incoming path of the large meteor, the data revealed that it wasn't necessarily the friction of the upper atmosphere the caused the explosion, but rather the pressure difference between the air in front of the rock and the air behind it.
"There's a big gradient between high-pressure air in front of the meteor and the vacuum of air behind it," Jay Melosh, a professor with Purdue University and co-author of the study, explains. "If the air can move through the passages in the meteorite, it can easily get inside and blow off pieces."
With the contrasting pressures surrounding the rock, and air seeping into the rock as it careened towards the ground, even a relatively strong chunk of rock would grow unstable and begin to fall apart. Given the speed at which meteors come flying in, that rapid disintegration takes the form of an explosion, and the resulting shockwave becomes the real damage-dealer for us here on the surface.
This might sound like a preferable outcome for any creatures that call Earth home, but that's only if you've allowed images of asteroid strikes from disaster movies cloud your judgment. In reality, a fast-moving space rock exploding in the air above a city can cause just as much — and in some cases more — damage than a ground strike. The meteor that detonated over Chelyabinsk exploded with the force of a small scale nuclear weapon, and injuries numbered in the hundreds.
The study is also quick to note that this type of airborne disintegration is only likely to happen with smaller objects, while particularly large and strong "planet killer" rocks will almost certainly remain unaffected.
U.S. President Donald Trump on Monday will sign a directive aimed at sending Americans back to the moon and eventually to Mars, the White House said. Trump will sign "Space Policy Directive 1" that orders NASA "to lead an innovative space exploration program to send American astronauts back to the Moon, and eventually Mars," spokesman Hogan Gidley said. Gidley said Trump's move is based on recommendations from the National Space Council.
The desperate need for mobile labs in Africa was made clear during the 2014 Ebola outbreak in West Africa. Testing for Ebola could take up to five days, as symptoms that initially presented as flu or malaria quickly turned deadly. Mobile labs sped the diagnostics process up to mere hours, but were only in place…
Several U.S.-based climate scientists are about to hit the jackpot, as French President Emmanuel Macron prepares to award them multi-year, all-expenses-paid grants to relocate to France. The "Make ...
Rabobank has launched Kickstart Food — a three-year programme focusing on four areas considered key to addressing the world’s sustainable food challenge. Nutrition: ensuring everyone has access to diets with balanced nutritional value. United Nations forecasts suggest that by 2050 the world population will be almost 9.8 billion people — a rise of more than 2 billion on current levels.
Around 25,000 of my colleagues flew to a conference, leaving a colossal carbon footprint in their wake. This weekend, 25,000 Earth, Sun, and planetary scientists from across the US and abroad flew to New Orleans for the annual American Geophysical Union’s Fall Meeting. As an Earth scientist and AGU member myself, I know the importance of their work.
The migration of tens of millions of red crabs across Australia's Christmas Island is a spectacular natural phenomenon, and Google Street View plans to capture it this year as part of their amazing Google Trekker gallery.
When one person asks another a question, it takes an average of 200 milliseconds for them to respond. This is so fast that we can’t even hear the pause. In fact, it’s faster than our brains actually work. It takes the brain about half a second to retrieve the words to say something, which means that in conversation, one person is gearing up to speak before the other is even finished. By listening to the tone, grammar, and content of another’s speech, we can predict when they’ll be done.
In the southern Egyptian city of Luxor, site of the ancient metropolis of Thebes, two new artifacts have been added to a place that is already crowded with mysteries of Egypt's distant past. The burial sites are located on the western bank of the Nile river, the water source that played such a central role in ancient Egyptian life and culture. The cemetery, or necropolis, in which the tombs are located is a known burial place of top officials from the 18th dynasty, according to the Associated Press.
The humble potato - drought-resistant, able to thrive in diverse soils, and enjoyed fried, steamed or baked - brought centuries of relative calm and prosperity to Europe after its introduction in the 16th century, a new study says. The blessings that flowed from this agricultural revolution helped ease the economic and societal pressures that can lead to costly and disastrous conflicts, says the report. The introduction of potatoes and the resultant increase in productivity "dramatically reduced conflict" both within and between states for some two centuries, it says.
Research has shown that people report the highest levels of happiness after the age of 55 in three key areas: their financial situation, their physical appearance, and their overall well-being. Meanwhile, in all three areas, people reported the lowest levels of happiness between the ages of 45 and 59, according to data from the Centre for Economic Performance, Proceedings of the National Academy of Sciences, and the General Social Survey.