Tag: science

A new dark matter detector has failed to detect any dark matter after its first three months of operation.

1:09 pm

The uncertainty of science: A new dark matter detector has failed to detect any dark matter after its first three months of operation.

Buried about a mile underground in a repurposed South Dakota gold mine, the LUX experiment searches for signs of dark matter particles colliding with the atoms in a vat of liquid xenon. During its first three months of operation, the detector found no such signals whatsoever. “We looked hard for these dark matter particles and we didn’t see anything,” says physicist Rick Gaitskell of Brown University, co-spokesperson for the LUX experiment. The results, presented at a seminar today and submitted to Physical Review Letters for publication, rule out a number of possible masses and characteristics for the particles that make up dark matter. The null result also conflicts with earlier experiments that had reported possible signals of dark matter.

This experiment has not proven that dark matter does not exist. It merely has narrowed significantly the kinds of particles that dark matter could be made of. That the results also contradict evidence from other detectors, however, leaves this specific area of science particularly uncertain.

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Geologists have determined that the magma reservoir under Yellowstone is much bigger than previously thought.

9:25 am

The uncertainty of science: Geologists have determined that the magma reservoir under Yellowstone is much bigger than previously thought.

Jamie Farrell, a postdoctoral researcher at the University of Utah, mapped the underlying magma reservoir by analysing data from more than 4,500 earthquakes. Seismic waves travel more slowly through molten rock than through solid rock, and seismometers can detect those changes.

The images show that the reservoir resembles a 4,000-cubic-kilometre underground sponge, with 6–8% of it filled with molten rock. It underlies most of the Yellowstone caldera and extends a little beyond it to the northeast.

The geologists also noted that the threat from a huge volcanic eruption is less of a concern than that of earthquakes.

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Europe turns off Planck

8:32 am

Europe turns off Planck.

Planck operated four-and-a-half years, three times longer than originally planned. Launched in May 2009 on an Ariane 5 rocket shared with ESA’s Herschel telescope, Planck measured the cosmic fingerprint of the Big Bang, detecting subtle variations in background light originating 380,000 years after the genesis of the universe.

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The great Martian dust storm of 1971.

8:49 am

The great Martian dust storm of 1971.

There has only been one comparable global dust storm on Mars since then. What made the 1971 even more significant historically is that the first human orbital probe had arrived at that very moment to record it.

By late 1971 and into January 1972 the storm abated, and Mariner 9 began to send back some spectacular images – a total of over 7,300 pictures that mapped the entire martian surface with resolutions ranging from 1 kilometer per pixel to as good at 100 meters per pixel.

The image here gives a sense of the magnitude of the storm. This was what the scientists began to see as the dust settled. The only visible features are the three great Tharsis Montes shield volcanoes, poking up through the haze in a line. The tallest of these reaches an altitude of over 18 kilometers. These peaks, and the enormous bulk of Olympus Mons had never been imaged by a spacecraft before, earlier flybys had missed them.

The late Bruce Murray (Caltech) was on the camera team and recalls, “there was a gradual clearing, like a stage scene, and three dark spots showed up.” The Mars that came out of the storm was a revelation, from these colossal mountains to the great rift of Valles Marineris and the steep valleys of Noctis Labyrinthus.

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Fresh impacts caused by Curiosity during landing

10:06 pm

impacts from Curiosity debris

The image on the right is a cropped close-up of a Mars Reconnaissance Orbiter image taken in early September that shows a fresh cluster of impacts, all smaller than six feet across. Nearby but not visible in this image are four larger craters about 12 to 15 feet in diameter. The impact cluster is located just northwest of Gale Crater and was not present in images taken before Curiosity’s arrival on Mars. The cluster is also in line with other impact craters produced by other debris dropped by Curiosity as it descended onto the Martian surface.

Scientists are at the moment unsure what spacecraft debris caused these impacts.

Assigning each of the impacts to specific pieces of hardware is a challenging puzzle, but it is thought that the four large craters were produced by two large tungsten weights that broke in half to make these four craters, or by pieces of the cruise stage, which was designed to break up in the atmosphere for planetary protection purposes, to kill any Earthly microbes.

The cluster imaged here adds to the mystery, and may have been produced by a piece of the cruise stage that traveled farther through the Martian atmosphere and was therefore more thoroughly fragmented by the time it crashed onto the surface.

Identifying the source of the debris is a challenging engineering problem that also has scientific interest. Knowing what caused the impacts and then studying how the surface was changed by them will tell geologists a great deal about the make up of that surface.

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Extreme weather events in 2013 are at an all time low.

9:53 am

Another global warming prediction fails: Extreme weather events in 2013 are at an all time low.

There have been many forecasts in the news in recent years predicting more and more extreme weather-related events in the US, but for 2013 that prediction has been way off the mark. Whether you’re talking about tornadoes, wildfires, extreme heat or hurricanes, the good news is that weather-related disasters in the US are all way down this year compared to recent years and, in some cases, down to historically low levels.

As I wrote back in April,

Global warming scientists have spent the past two decades telling us that we were all gonna die from increasing temperatures caused by the increase in CO2. Now that this prediction has proved false, they apparently are shifting gears. Instead, it is extreme events — big storms, long droughts, intense heatwaves — that are going to kill us.

But not only have they no evidence that the increase in CO2 will cause these extreme events, there is no evidence that more of these extreme events are even occurring.

In other words, these stories are mere political advocacy. They have nothing to do with science, but with propaganda, based on fantasy with the goal of trying to convince everyone that we are all gonna die if we don’t do exactly what these scientists say. [emphasis in original]

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A recently discovered 1.8 million year old skull suggests that the multiple human species theorized by paleontologists were actually just one.

3:39 pm

The uncertainty of science: A recently discovered 1.8 million year old skull suggests that the multiple human species theorized by paleontologists were actually just one. More details here.

It is one of five early human skulls — four of which have jaws — found so far at the site, about 100 kilometers (62 miles) from the capital Tbilisi, along with stone tools that hint at butchery and the bones of big, saber-toothed cats. Lead researcher David Lordkipanidze, director of the Georgian National Museum, described the group as “the richest and most complete collection of indisputable early Homo remains from any one site.”

The skulls vary so much in appearance that under other circumstances, they might have been considered different species, said co-author Christoph Zollikofer of the University of Zurich. “Yet we know that these individuals came from the same location and the same geological time, so they could, in principle, represent a single population of a single species,” he said. The researchers compared the variation in characteristics of the skulls and found that while their jaw, brow and skull shapes were distinct, their traits were all within the range of what could be expected among members of the same species.

I have always thought that paleontologists were too quick to name each new major find as a new species. Among all species there is always a wide variety of features. One person is tall. Another has a big forehead or head. This discovery reinforces this idea. The five skulls were all found in the same place, from the same group. Yet they were very different from each other.

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A bogus scientific paper, with numerous errors, was accepted for publication by more than 150 peer-reviewed scientific journals.

12:36 pm

A bogus scientific paper, with numerous errors, was accepted for publication by more than 150 peer-reviewed scientific journals.

The scientist purposely wrote a paper that should have been unacceptable for publication in order to see if peer-review would spot the problems. What he found was that more than half the journals to which he submitted didn’t notice or care, and accepted the paper as is.

The journals in this case were open-access, meaning that they are free to readers but charge authors money for publication. Thus, rejecting papers is against their financial interest. Nonetheless, the number of journals willing to be unethical is quite disturbing, and reveals a rottenness lurking in the heart of the science field that no one wants to talk about.

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Scientists have found a fossil of a mosquito with traces of blood in its engorged abdomen.

8:30 am

Scientists have found a fossil of a mosquito with traces of blood in its engorged abdomen.

Although scientists have found fossils of suspected blood-sucking insects, the creatures’ feeding habits have mostly been inferred from their anatomy or the presence of blood-borne parasites in their guts. But Greenwalt’s fossilized mosquito contains molecules that provide strong evidence of blood-feeding among ancient insects back to 46 million years ago. It is a fortunate find. “The abdomen of a blood-engorged mosquito is like a balloon ready to burst. It is very fragile,” says Greenwalt. “The chances that it wouldn’t have disintegrated prior to fossilization were infinitesimally small.”

Some news reports have implied that the scientists had found actual blood 46 million years old. This is not the case. They found “large traces of iron and the organic molecule porphyrin — both constituents of haemoglobin, the oxygen-carrying pigment found in vertebrate blood. These molecules were either rare or absent in the abdomen of a fossilized male mosquito (which does not drink blood) of the same age, found at the same location.” Still, even though this isn’t actual blood, the evidence is good and so the result is quite cool.

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Scientist right now think it is a toss-up whether Comet ISON will survive its dive past the sun on November 28.

10:43 am

Scientist right now think it is a toss-up whether Comet ISON will survive its dive past the sun on November 28.

Essentially, they have no idea what will happen. They know most of the factors effecting the comet, but cannot predict the result. If the comet breaks up, however, it will be very cool, as this will probably be the largest comet ever seen by astronomers to do this.

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Two days after its flyby of Earth, Jupiter probe Juno remains in safe mode.

10:38 am

Two days after its flyby of Earth, Jupiter probe Juno remains in safe mode.

The Juno spacecraft is in a healthy and stable state, with its tractor-trailer-size solar panels pointed toward the sun. The mission team is in communication with Juno and has seen no sign of any failures in the probe’s subsystems or components, said project manager Rick Nybakken of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. So Juno’s handlers plan to take their time and do a thorough investigation before attempting to bring all of the spacecraft’s systems back online.

In other words, there is no rush to take the spacecraft out of safe mode. It is far better to figure out exactly what is going on first.

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One hundred days to wake-up for Europe’s Rosetta comet probe.

8:26 am

One hundred days to wake-up for Europe’s Rosetta comet probe.

Rosetta was launched on 2 March 2004, and through a complex series of flybys – three times past Earth and once past Mars – set course to its destination: comet 67P/Churyumov–Gerasimenko. It also flew by and imaged two asteroids, Steins on 5 September 2008 and Lutetia on 10 July 2010. In July 2011 Rosetta was put into deep-space hibernation for the coldest, most distant leg of the journey as it travelled some 800 million kilometres from the Sun, close to the orbit of Jupiter. The spacecraft was oriented so that its solar wings faced the Sun to receive as much sunlight as possible, and it was placed into a slow spin to maintain stability.

Now, as both the comet and the spacecraft are on the return journey back into the inner Solar System, the Rosetta team is preparing for the spacecraft to wake up.
Rosetta mission milestones 2014-2015 Rosetta’s internal alarm clock is set for 10:00 GMT on 20 January 2014.

The first images are expected back in May 2014.

Posted as we approach the Arkansas-Texas border.

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An eleven year old’s experiment in brewing beer in space will fly to ISS on the next Cygnus cargo flight in December.

6:17 pm

An eleven year old’s experiment in brewing beer in space will fly to ISS on the next Cygnus cargo flight in December.

The tiny brewery is set up inside a 6-inch-long (15 centimeters) tube, filled with separated hops, water, yeast and malted barley — all of the key ingredients used to make beer — and will be delivered to the station by the commercial firm NanoRacks. An astronaut aboard the station will shake up the mixture to see how the yeast interacts with the other ingredients in the beer. “I really didn’t expect this from the start,” Bodzianowski told KDVR, a Fox affiliate in Denver. “I really just designed my experiment to get a good grade in my class.”

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China complains about the ban of its scientists at a NASA Kepler conference.

5:40 am

China complains about the ban of its scientists at a NASA Kepler conference.

The meeting is a key event for scientists searching for planets beyond the solar system. NASA has rejected applications from Chinese nationals, citing a new security law. In Beijing, foreign ministry spokeswoman Hua Chunying called the move “discriminatory”. The conference is for US and international teams who work on Nasa’s Kepler space telescope program. It will be held at Nasa’s Ames research centre in California next month.

And I say, tough. China does not distinguish between civilian and military research, and in fact has often used its scientists to do espionage, stealing both military and industry secrets in the process.

Posted in Virginia as we pass through Harrisonburg. Note again that Diane, not I, is doing the driving.

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Engineers hope Juno’s Earth flyby yesterday will help solve a mystery seen in previous flybys by unmanned probes.

5:32 am

The uncertainty of science: Engineers hope Juno’s Earth flyby yesterday will help solve a mystery seen in previous flybys by unmanned probes.

Since 1990, mission controllers at ESA and NASA have noticed that their spacecraft sometimes experience a strange variation in the amount of orbital energy they pick up from Earth during flybys, a technique routinely used to fling satellites deep into our Solar System. The unexplained variation is noticed as a tiny difference in the expected speed gained (or lost) during the passage.

The variations are extremely small: NASA’s Jupiter probe ended up just 3.9 mm/s faster than expected when it swung past Earth in December 1990. The largest variation– a boost of 13.0 mm/s – was seen with NASA’s NEAR asteroid craft in January 1998. Conversely, the differences during swingbys of NASA’s Cassini in 1999 and Messenger in 2005 were so small that they could not be confirmed.

The experts are stumped.

It is likely that these small variations are related in some way with simple engineering and not some unknown feature of gravity. Nonetheless, it remains a mystery.

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