A sunstone, used by mariners to judge the position of the Sun when it is cloudy, has been found at a 16th century shipwreck.

A sunstone, used by mariners to judge the position of the Sun when it is cloudy, has been found at a 16th century shipwreck.

A previous study showed that calcite crystals reveal the patterns of polarized light around the sun and, therefore, could have been used to determine its position in the sky even on cloudy days. That led researchers to believe these crystals, which are commonly found in Iceland and other parts of Scandinavia, might have been the powerful “sunstones” referred to in Norse legends, but they had no archaeological evidence to support their hypothesis—until now.

We don’t need no solar maximum

It is that time again! Today, March 4, NOAA released its monthly update of the Sun’s sunspot cycle, covering the period of February 2013. As I do every month, I am posting this latest graph, with annotations to give it context, below the fold.

Once again, the Sun has shown a complete inability to produce sunspots, at the very moment it had been predicted to be rising towards its maximum in the sunspot cycle. The numbers in February plunged from the tepid rise we saw in January to below the crash we saw in December. Right now, when the Sun is supposed to peaking, it is instead producing sunspots in numbers as low as seen in 2011, at the very end of the last solar minimum.
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Scientists are considering revising the guidelines for heart risk as determined by your cholesterol levels.

The uncertainty of science: Scientists are considering revising the guidelines for heart risk as determined by your cholesterol levels.

The ATP IV committee has pledged to hew strictly to the science and to focus on data from randomized clinical trials, says committee chairman Neil Stone, a cardiologist at Northwestern University School of Medicine in Chicago. If so, Krumholz argues, LDL [cholesterol] targets will be cast aside because they have never been explicitly tested. Clinical trials have shown repeatedly that statins reduce the risk of heart attack and stroke, but lowering LDL with other medications does not work as well. The benefits of statins may reflect their other effects on the body, including fighting inflammation, another risk factor for heart disease. [emphasis mine]

In other words, the assumption that’s been pushed for more than a decade that lowering your cholesterol will lower your risk of heart attack has never been tested or proven. If this isn’t science by myth I don’t know what is.

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons.

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons. Key quote:

Vulcan was a late addition to the Pluto moon name contenders, and pulled into the lead after Shatner, building on his Capt. James T. Kirk persona, plugged the name on Twitter. Vulcan, the home planet of Kirk’s alien-human hybrid first officer Spock, is not just a fictional world in the Star Trek universe. It is also the name of the god of fire in Roman mythology, and officials at SETI added the sci-fi favorite to the ballot for that reason.

New data has allowed scientists to lower the chance that the asteroid Apophis will hit the Earth in a future orbit.

New data has allowed scientists to lower the chance that the asteroid Apophis will hit the Earth in a future orbit.

Recent observations from Pan-STARRS PS1 telescope at Haleakala, Hawaii have reduced the current orbital uncertainty by a factor of 5, and radar observations in early 2013 from Goldstone and Arecibo will further improve the knowledge of Apophis’ current position. However, the current knowledge is now precise enough that the uncertainty in predicting the position in 2029 is completely dominated by the so-called Yarkovsky effect, a subtle nongravitational perturbation due to thermal re-radiation of solar energy absorbed by the asteroid. The Yarkovsky effect depends on the asteroid’s size, mass, thermal properties, and critically on the orientation of the asteroid’s spin axis, which is currently unknown. This means that predictions for the 2029 Earth encounter will not improve significantly until these physical and spin characteristics are better determined.

The new report, which does not make use of the 2013 radar measurements, identifies over a dozen keyholes that fall within the range of possible 2029 encounter distances. Notably, the potential impact in 2036 that had previously held the highest probability has been effectively ruled out since its probability has fallen to well below one chance in one million. Indeed only one of the potential impacts has a probability of impact greater than 1-in-a-million; there is a 2-meter wide keyhole that leads to an impact in 2068, with impact odds of about 2.3 in a million.

The second paragraph basically says that the keyholes that might bring Apophis back to Earth are very small, making it unlikely that the asteroid will fly through any one of them in 2029. The first paragraph however notes that it will be impossible to chart the asteroid’s course accurately enough to rule out this possibility until we have more data on the asteroid itself.

In an interview in Australia, the head of the IPCC has admitted that the climate has stopped warming now for the past seventeen years.

Consensus! In an interview in Australia, the head of the IPCC has admitted that the climate has stopped warming now for the past seventeen years.

No computer climate model offered in any IPCC report predicted this long pause in warming. They all instead insisted that because of the increase of carbon dioxide in the atmosphere, the global temperature would have to rise, and do so quickly and with catastrophic results.

In other words, those models were wrong. The climate is very complicated, and we don’t yet understand very well how it functions.

Using Kepler scientists have discovered a three planet solar system with one planet slightly larger than our Moon.

Using Kepler astronomers have discovered a three planet solar system with one planet slightly larger than our Moon.

Kepler-37’s host star belongs to the same class as our sun, although it is slightly cooler and smaller. All three planets orbit the star at less than the distance Mercury is to the sun, suggesting they are very hot, inhospitable worlds. [The moon-sized] Kepler-37b orbits every 13 days at less than one-third Mercury’s distance from the sun. The estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin), would be hot enough to melt the zinc in a penny. Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively.

Scientists have released some results from their look at asteroid 2012 DA14 during its fly-by last week.

Scientists have released some results, including video, from their look at asteroid 2012 DA14 during its fly-by last week. Key quote:

The asteroid’s path was perturbed by Earth’s gravitational field in such a way that it won’t come as close in the foreseeable future.

The video, which I have embeded below the fold, was produced from radar data. It clearly shows the asteroid’s rotation.
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A new poll of Earth scientists has found that a majority are skeptical of human-caused global warming.

Consensus! A new poll of Earth scientists has found that a majority are skeptical of human-caused global warming.

Only 36 percent of geoscientists and engineers believe that humans are creating a global warming crisis, according to a survey reported in the peer-reviewed Organization Studies. By contrast, a strong majority of the 1,077 respondents believe that nature is the primary cause of recent global warming and/or that future global warming will not be a very serious problem.

This is fun to note, but this poll is as worthless in determining the climate of the Earth as every previous poll that said the opposite. What matters is the data. However, this quote about the poll is significant:
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Largest in a century.

More on today’s Russian meteorite: Largest in a century.

My earlier skepticism appears incorrect. This impact actually happened.

Note the article’s sense of outrage and panic that we aren’t looking for these types of rocks:

Although a network of telescopes watches for asteroids that might strike Earth, it is geared towards spotting larger objects — between 100 metres and a kilometre in size. “Objects like that are nearly impossible to see until a day or two before impact,” says Timothy Spahr, Director of the Minor Planet Center in Cambridge, Massachusetts, which tracks asteroids and small bodies. So far as he knows, he says, his centre also failed to spot the approaching rock.

Yet, today’s impact actually illustrates the wisdom of excluding this kind of small asteroid from searches. They aren’t big enough to do serious harm, and trying to find them would hamper searches for larger asteroids that do pose a serious risk.

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