Tag: science

The strange egg-shaped dwarf planet Haumea is apparently also covered with ice

8:35 pm

Truly alien: The strange egg-shaped dwarf planet Haumea is apparently also covered with crystallised ice.

“Since solar radiation constantly destroys the crystalline structure of ice on the surface, energy sources are required to keep it organized. The two that we have taken into consideration are that able to generate radiogenic elements (potassium-40, thorium-232 and uranium-238) from the inside, and the tidal forces between Haumea and its satellites,” [explained] Benoit Carry, co-author of the study and a researcher at the ESAC Centre of the European Space Agency (ESA) in Madrid (Spain).

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The science remains uncertain

5:38 pm

Two papers published this week by the American Geophysical Union once again indicate that the science of climate change remains exceedingly uncertain. More significantly, the models that try to predict the future of the Earth’s climate continue to appear unreliable, with such large margins of error that it is at this time foolish to make any policy based on their predictions.

diagram of Atlantic currents

The first paper took a close look at the deep water currents in the Atlantic to see if it could track changes to what the authors’ call the Atlantic meridional overturning circulation (AMOC), more generally referred to as the Atlantic conveyor belt. This conveyor belt begins with the sinking of salty dense water in the northeast Atlantic off of Europe and Africa. The deep water current then travels south and into the Indian and Pacific Oceans where it comes to the surface only to flow back to the Atlantic, traveling north along the coast of North America as the Gulf Stream, bringing with it the warm temperatures that make Europe’s climate much warmer than its latitude would normally suggest.

According to most global warming models, higher temperatures should cause the glaciers in the Arctic and Greenland to melt, thereby pouring an increased amount of fresh water into the North Atlantic. This infusion of fresh water is then expected to lower the salinity and density of the Atlantic water, thus preventing it from sinking and thus acting to slow the conveyor belt, and possibly even causing it to shut down. The consequence would be no more Gulf Stream to warm the climate of Europe.

In other words: Disaster! Death! Destruction! All caused by global warming!

Unfortunately for these global warming models, the paper above found no trend at all. The conveyor belt is not slowing, as predicted. To quote the paper’s abstract:
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The Crab Nebula erupts with flares six days

10:37 pm

In mid-April the Crab Nebula erupted for six days, repeatedly emitting the most powerful flares ever recorded from the supernova remnant.

Scientists think the flares occur as the intense magnetic field near the pulsar undergoes sudden restructuring. Such changes can accelerate particles like electrons to velocities near the speed of light. As these high-speed electrons interact with the magnetic field, they emit gamma rays.

To account for the observed emission, scientists say the electrons must have energies 100 times greater than can be achieved in any particle accelerator on Earth. This makes them the highest-energy electrons known to be associated with any galactic source. Based on the rise and fall of gamma rays during the April outbursts, scientists estimate that the size of the emitting region must be comparable in size to the solar system.

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Data leaks from particle hunters raise questions about controlling scientific secrecy

11:38 am

Recent data leaks from particle hunters is now raising questions among physicists about the question of controlling scientific secrecy. To me, the most significant quote from the article was this:

“Should leakers or bloggers be punished for making early findings public?

That this question is even asked by someone in the science field is disturbing. Though the leaks might be annoying and counter to the agreements the scientists signed when they joined these various projects, I wonder how the author expects such punishment to be administrated. And who would do it? And should such punishment apply to everyone, or just to the participating scientists?

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Dark matter mysteries

10:23 am

Every year, as part of its educational and research mission, the Space Telescope and Science Institute in Baltimore, Maryland holds a science symposium that focuses one of the big questions of astronomy, inviting over a hundred scientists to come and give their individual perspectives on the state of the field.

This year’s symposium ended yesterday, and the subject was the mysteries of dark matter. Though I wasn’t able to attend the symposium itself, they held a workshop for journalists yesterday, which I did attend. (You can watch the webcast here.)

So, what is dark matter?

First of all, it isn’t dark energy. Dark energy is that mysterious unknown phenomenon that is causing — on vast scales of many billions of light years — the expansion of the universe to accelerate rather than decelerate. It has nothing to do with the question of dark matter.

Second, no one knows. All that scientists do know is that objects in the outer regions of galaxies as well as the galaxies themselves don’t move at the speeds and directions expected if their known mass and gravity were the only forces influencing them. In order to successfully plot their orbits and motions, astronomers have to add a gigantic halo of extra mass, which they have dubbed “dark matter” because it is unseen, undetected, and completely invisible.
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U.N. Forces from Nepal introduced cholera to Haiti

9:10 am

We’re here to help you! U.N. rescue forces from Nepal were the ones who introduced cholera to Haiti after the 2010 earthquake.

Soon after the start of the outbreak, which has sickened close to 300,000 people and killed nearly 5000, Haitians fingered the United Nations Stabilization Mission in Haiti (MINUSTAH), which has a camp populated by Nepalese soldiers in Mirebalais in the Centre Department, very close to where the first cholera cases occurred. The camp was also blamed in a leaked epidemiological report by a French cholera expert, Renaud Piarroux of the University of the Mediterranean in Marseille, written at the request of the Haitian government. Several genetic studies showed that the Haitian cholera strain strongly resembled others found recently in South Asia—although none pinpointed Nepal specifically.

Yet some cholera scientists—including Rita Colwell, seen by many as a giant in the field—contended that the bacteria had more likely been present in local waters, and that the outbreak had been triggered by a combination of environmental factors.

Rita Colwell is hardly what I’d call a “giant in the field,” at least nowadays. Though her biography lists a lot of research work, the last decade she has spent most of her time playing politics as a political appointee, going from one government agency to another.

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The Sun in April – Steady as she goes!

10:04 am

The monthly updated graph for April of the Sun’s solar cycle sunspot activity was posted yesterday by NOAA’s Space Weather Prediction Center. You can see it below.

Though the Sun remained active, you can see that the steep increase in sunspot activity that occurred in March has ceased. At the moment it looks as if the Sun’s sunspot activity is following the most recent scientific prediction, more or less exactly, though the small dip in April puts the numbers slightly below that prediction.

All in all, we still appear to be headed to the weakest solar maximum in two hundred years.

April Sunspot activity

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