Category: Essays And Commentaries

Long essays or op-ed length commentaries on the issues of the day or on topics of special interest.

A global view of Vesta

3:32 pm

Vesta

The accumulating data from Dawn has now allowed scientists to compile a global picture of the varied surface makeup of the asteroid Vesta.

The colors were chosen to highlight differences in surface composition that are too subtle for the human eye to see. Scientists are still analyzing what some of the colors mean for the composition of the surface. But it is clear that the orange material thrown out from some impact craters is different from the surrounding surface material. Green shows the relative abundance of iron. Parts of the huge impact basin known as Rheasilvia in Vesta’s southern hemisphere, for instance, have areas with less iron than nearby areas.

It also makes for a very nice image of the giant asteroid.

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Cave exploration in the western mountains

1:01 pm

scree slope
Anthony Smith struggling up a scree mountain slope.

I have only visited Nevada twice before, and those visits had been limited to the area around Las Vegas. Thus, my impression of the state had been similar to what most other people assume: a big ostentatious urban city surrounded by boring flat deserts.

Instead what I found is that Nevada is probably one of the most beautiful states in the nation. It has many mountain ranges, interspersed with wide flat valleys, a number of which have lakes or swampy areas because the water is trapped there, draining neither to the Pacific or Atlantic.

Yet, it is desert country. The limited amount of water means that the state is lightly populated, and the few farms or ranches that you pass actually act to amplify the feeling of emptiness. This is further enhanced by the frequent mountain ranges. Every time you cross over a range, you find yourself high in the air with a spectacular view of the vast valleys below.

The Forest Service job that I was part of this past week was focused on inventorying and surveying a number of known caves covering a large area in northeastern Nevada. The work had actually started several years earlier, so that this particular week was the final wrap up, mapping the last few known caves on the list while also ridge-walking several different canyons in an effort to find some new discoveries.
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Caving in Nevada

8:06 am

I finally have an hour free here in Nevada.

For the past three days we have been intensely hiking up mountains over a vast area of Nevada. The goal has been to locate and map caves for the Forest Service in some of the most remote areas of the state. So far we have focused on mapping known caves, putting the possible discoveries aside for later work.
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Off to Nevada

5:00 am

Nevada

For the next seven days my daytime posting is going to be spotty, as I will be in some remote areas of Nevada working on an on-going Forest Service project to inventory and survey caves in an area in the northeastern area of the state. The project is mostly over, but as I have surveyed, sketched, and done the cartography for many eastern U.S. caves, the guy running the project asked if I would be interested in participating. Interested? I was thrilled.

Though we will be in a somewhat remote area, I still hope to post periodically during the week, not only about the usual topics but also about some of the caves we will have surveyed, some of which are rarely visited. I will also try to post some pictures of the spectacular country we expect to visit. (The photo on the right was provided to me by Tom Gilleland, who is running the project.) Stay tuned.

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A failed public works project — from the year 1350 AD

4:02 pm

Casa Grande

Yesterday my wife Diane and I took my 94-year-old mother on a sightseeing trip to see the Casa Grande ruins southeast of Phoenix, “the largest known structure left of the Ancestral People of the Sonoran Desert.”

This four story high structure was built around 1350 AD from bricks made of concrete-like caliche mud, with the floors and roofs supported by beams of pine, fir, and juniper brought from as far away as fifty miles. (The rooflike structure above the ruins was built by the National Park Service in order to protect it from rain.)

Though impressive, I must admit I’ve seen far more impressive American Indian ruins elsewhere. Casa Grande, which means “Great House” in Spanish, suffered as a tourist attraction from two faults:
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Shut it down

8:25 am

Our government in action: An NIH nationwide study to track hundreds of thousands of children from birth to age 21 is wracked with budget and management problems.

All told, this study has already cost the taxpayers almost a billion dollars for the enrollment of only 4,000 children, not the 100,000 envisioned. That’s about $250,000 per child, an amount that seems incredibly high.

In addition to the above problems, it appears there are scientific ones as well:
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Killing private space

9:31 am

The financial foolishness in Congress, by Republicans this time, continues. In making its budget recommendations for NASA, the report [pdf] of the House Appropriations Commerce, Justice, Science, and Related Agencies subcommittee also demands that NASA immediately choose one commercial company for its commercial space program. (Hat tip to Clark Lindsey for spotting this.)

The number of ways this action is counter-productive almost can’t be counted.
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More problems for Dark Matter

9:29 am

Vast Polar Structure

A new study by astronomers has found a vast structure of satellite galaxies and star clusters aligned perpendicular to the Milky Way and extending outward above and below the galaxy’s nucleus by as much as a million light years.

In their effort to understand exactly what surrounds our Galaxy, the scientists used a range of sources from twentieth century photographic plates to images from the robotic telescope of the Sloan Deep Sky Survey. Using all these data they assembled a picture that includes bright ‘classical’ satellite galaxies, more recently detected fainter satellites and the younger globular clusters.

“Once we had completed our analysis, a new picture of our cosmic neighbourhood emerged”, says Pawlowski. The astronomers found that all the different objects are distributed in a plane at right angles to the galactic disk. The newly-discovered structure is huge, extending from as close as 33,000 light years to as far away as one million light years from the centre of the Galaxy.

An animation illustrating this galactic distribution is posted below the fold. You can read the actual preprint paper here.

The problem with this polar alignment with the Milky Way’s core is that the theories for explaining the distribution of dark matter do not predict it.
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It’s not just a good idea, it’s the law!

8:59 am

Mexico has passed its own very strict climate change law.

The new law contains many sweeping provisions to mitigate climate change, including a mandate to reduce emissions of carbon dioxide by 30% below business-as-usual levels by 2020, and by 50% below 2000 levels by 2050. Furthermore, it stipulates that 35% of the country’s energy should come from renewable sources by 2024, and requires mandatory emissions reporting by the country’s largest polluters.

Some predictions:
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Dark matter disappears

9:15 am

The uncertainty of science: A new study has found no evidence of dark matter within 13,000 light years of the Sun, something that had not been expected.

According to widely accepted theories, the solar neighborhood was expected to be filled with dark matter, a mysterious invisible substance that can only be detected indirectly by the gravitational force it exerts. But a new study by a team of astronomers in Chile has found that these theories just do not fit the observational facts. This may mean that attempts to directly detect dark matter particles on Earth are unlikely to be successful.

These findings will be as controversial as the now abandoned faster-than-light neutrino results last fall. Here, however, the new data is likely going to be more robust, which will cause the entire astrophysical community some real conniptions.
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