Tag: science

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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