Category: Essays And Commentaries

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

The Moon: a desert after all?

10:10 am

LEND data of lunar south pole

The uncertainty of science: A new science paper, published Saturday in the Journal of Geophysical Research – Planets,, has found that there is much less water ice trapped in the permanently shadowed craters of the lunar poles than previously thought. From the abstract:

This means that all [permanently shadowed regions], except those in Shoemaker, Cabeus and Rozhdestvensky U craters, do not contain any significant amount of hydrogen in comparison with sunlit areas around them at the same latitude.

And from the paper’s conclusion:

[E]ven now the data is enough for definite conclusion that [permanently shadowed regions] at both poles are not reservoirs of large deposits of water ice.

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The real estate crash: We’ve only just begun

11:37 am

A real estate industry group today announced that there was a nine percent jump in foreclosures during the month of May.

RealtyTrac reported that 205,990 U.S. properties received filings last month, including default notices, scheduled auctions and bank repossessions, marking the first monthly increase since January. Bank repossessions climbed steeply, up 7% to 54,844, after hitting a four-year low in April.

The report also noted that foreclosures made up 26% of U.S. home sales in first quarter and that more than 30% of mortgage borrowers were still underwater.

As someone who just moved to Tucson and spent more than six months searching for and finally purchasing a home, I can add a bit of personal experience to these dry statistics. And my perspective is sadly not encouraging.
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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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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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Senate panel proposes major NASA/NOAA budget changes

8:59 pm

A Senate panel today proposed shifting the responsibility for building weather satellites from NOAA to NASA.

It is very unclear from this article why the Senate panel proposed this shift. They claim it will save money but I don’t see how.

What I can guess is that there is probably a turf war going on in Congress over this money. For example, shifting these weather satellites to NASA almost certainly means that the Goddard Space Flight Center in Maryland will get more money, which is almost certainly why Senator Barbara Mikulski (D-Maryland) is for it.

One thought however: NASA generally focuses on individual missions, not long term operational stuff like weather. I suspect it probably is not a good idea to give this work to NASA.

The same article above also outlined the panel’s proposals for other areas of NASA’s budget. To me, the key issue is the budget for commercial space. The White House requested $830 million. The Senate panel has instead proposed $525 million.
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Coming and going

9:10 am

There are really only two important stories today concerning space exploration. The story that is getting the most coverage is the big news that the space shuttle Discovery is making its last flight, flying over Washington, DC, as it is delivered to the Smithsonian for permanent display.

Of these stories, only Irene Klotz of Discovery News seems to really get it. This is not an event to celebrate or get excited about. It is the end of an American achievement, brought to a close probably three to five years prematurely so that the United States now cannot even send its own astronauts to its own space station.

The other news, actually far more important, has gotten far less coverage, and includes three different stories all really about the same thing.
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An up and down Sun, for real this time

2:19 pm

Though I am a bit late in covering this story (due to moving, unpacking, Passover, and an unexpected visit to the dentist), NOAA’s Space Weather Prediction Center on April 9 released its monthly update of the ongoing sunspot cycle of the Sun. The most recent graph is below the fold.

In order to understand the context of this new graph, however, it is necessary to make a correction and clarification.
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Passover

10:56 am

For the next two days posting will be light. I am in Chicago visiting family for Passover, the annual Jewish holiday celebrating the release of the Jews from slavery in Egypt. During the Seder meal, Jews read the Haggadah, which retells the story of the Jewish slavery in Egypt and their escape, with the idea of reminding each person what is like to be a slave, and then to be free. As it says in the Haggadah,

In every generation each individual is bound to regard himself as if he had gone personally forth from Egypt.

Tonight, this is what Jews do. It would be nice if all people reflected on this and did the same.

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The actual cost to launch

7:30 am

In writing this short post on the efforts of Lockheed Martin and Orbital Sciences to launch rockets for the small satellite market, Clark Lindsey made this comment:

It costs around $50 million to launch a Orbital Sciences Minotaur 4, which can put 1,730 kg into LEO while the Lockheed’s Athena 2 will cost around $65 million to put 1,712 kg into LEO. SpaceX currently posts charges $54M – $59.5M for launching to LEO 10,450 kg (equatorial) and 8,560 kg (polar). If SpaceX is able to sustain these prices in routine operation, it will obviously result in some disturbance to the launch industry.

Let’s deconstruct these numbers again, this time listing them by the cost per kilogram:
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