Tag: ice

Researchers discover a new kind of water ice

9:59 am

Researchers have discovered a new kind of water ice that appears to match the density and structure of liquid water.

he ice is called medium-density amorphous ice. The team that created it, led by Alexander Rosu-Finsen at University College London (UCL), shook regular ice in a small container with centimetre-wide stainless-steel balls at temperatures of –200 ˚C to produce the variant, which has never been seen before. The ice appeared as a white granular powder that stuck to the metal balls. The findings were published today in Science.

The abstract for the paper can be read here.

Not only does this discovery suggest that there are many possible states of water ice, with a range of properties, this new type of ice could help explain many of the features we see on planets like Mars that appear to have been caused by flowing water. Mars has a lot of glacial ice, much of which might not be ice as we assume.

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Antarctica data adds weight to hypothesis that glaciers shaped Mars

10:01 am

New data from an Antarctica ice core strengthens the hypothesis that the flow of glaciers, not liquid water, helped shape the meandering canyons on Mars.

The data was the discovery of the mineral jarosite deep within the south pole ice-cap. Jarosite needs water to form. Previously it was generally believed it formed in conjunction with liquid flowing water. On Mars, which appears to have lots of jarosite, scientists have struggled for decades to figure out how enough liquid water could have existed on the surface of Mars to produce it.

The discovery of jarosite deep inside the Antarctic ice cap now suggests that it can form buried in ice, not liquid water. According to the scientists,

the jarosite was born within massive ice deposits that might have blanketed [Mars] billions of years ago. As ice sheets grew over time, dust would have accumulated within the ice—and may have been transformed into jarosite within slushy pockets between ice crystals.

From the paper’s conclusions:

The occurrence of jarosite in TALDICE [in Antarctica] supports the ice-weathering model for the formation of Martian jarosite within large ice-dust deposits. The environment inside the Talos Dome ice [in Antarctica] is isolated from the Earth atmosphere and its conditions, including pressure, temperature, pH and chemistry, provides a suitable analogue for similar Martian settings. Dust deposited at Talos Dome is also similar to Martian atmospheric dust, being both mostly basaltic. Within thick ice deposits it is likely that the environment would be similar at Talos Dome and under Mars-like conditions since both settings would contain at cryogenic temperatures basaltic dust and volcanogenic and biogenic (for Antarctic only) sulfur-rich aerosols. … Considering this context, it is reasonable that the formation of jarosite on Mars involves the interaction between brines and mineral dust in deep ice, as observed in TALDICE. This mechanism for Martian jarosite precipitation is paradigm changing and strongly challenges assumptions that the mineral formed in playa settings.

Playa settings are places where there is standing liquid water, slowing drying away.

This result is another piece of evidence that ice and glaciers were the cause of the Martian terrain that to Earth eyes for decades was thought to have formed by flowing water. It also continues what appears to be a major shift on-going in the planetary science community, from the idea of liquid water on Mars to that of a planet dominated by glacial and ice processes.

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ICE & FBI agents took bribes

8:43 am

Agents of both ICE and the FBI took bribes to provide protection as well as cook the records for an indicted Los Angeles lawyer.

We only know this because conviction of the lawyer says so. The FBI agent is named and has been charged. The ICE agent however remains a mystery, for unknown reasons.

But don’t worry. The government is wise and all-knowing. The best thing we can do during this Wuhan panic is give them a lot of power!

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Scientists now think it is possible for there to be floating methane ice on the lakes of Titan.

11:56 am

Scientists now think it is possible for there to be floating methane ice on the lakes of Titan.

Up to this point, Cassini scientists assumed that Titan lakes would not have floating ice, because solid methane is denser than liquid methane and would sink. But the new model considers the interaction between the lakes and the atmosphere, resulting in different mixtures of compositions, pockets of nitrogen gas, and changes in temperature. The result, scientists found, is that winter ice will float in Titan’s methane-and-ethane-rich lakes and seas if the temperature is below the freezing point of methane — minus 297 degrees Fahrenheit (90.4 kelvins). The scientists realized all the varieties of ice they considered would float if they were composed of at least 5 percent “air,” which is an average composition for young sea ice on Earth. (“Air” on Titan has significantly more nitrogen than Earth air and almost no oxygen.)

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According to this article, the water-ice discovered at Shackleton Crater is insufficient for human settlement.

8:44 am

The uncertainty of science: According to this article, the water-ice discovery announced yesterday at Shackleton Crater is insufficient for human settlement.

The latest LRO data indicate “that water is not there … in a way that would facilitate human exploration,” says planetary scientist Maria Zuber, who led the team analyzing the data.

If the signatures the team saw in the soils on the crater floor do indicate water, how much water might there be? Roughly 100 gallons – enough to fill two or three residential rain barrels – spread over a surface of about 133 square miles. Leave the swim-suit at home. “This is not like Mars,” says Dr. Zuber, a professor at the Massachusetts Institute of Technology in Cambridge, in an interview. On the red planet, explorers would find thick layers of icy soil in many locations just by turning over a shovelful or two of topsoil. [emphasis mine]

This story seems to answer my question about Zuber’s participation in the water in Shackleton paper as well as the previous paper saying there is much less water on the Moon than previously believed. It also raises questions about the journalism work of many of the other stories published in the past few days, which heavily touted the possibility of water in Shackleton.

I intend to dig into this story a bit more. Stay tuned.

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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.

» Read more

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“Unable to pass its immigration agenda through legislation, the Administration is now implementing it through agency policy.”

7:11 pm

From the head of union representing agents of Immigration and Customs Enforcement (ICE): “Unable to pass its immigration agenda through legislation, the Administration is now implementing it through agency policy.” And if you still have doubts about the unwillingness of the Obama administration to enforce the law, there’s also this quote:

Our officers are already under orders not to make arrests or even talk to foreign nationals in most cases unless another agency has already arrested them; you won’t find that written in any public ICE policy.

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Antarctic increase in sea ice since 1970 cannot be explained by ozone hole

5:37 pm

In another paper published today in the Geophysical Research Letters of the American Geophysical Union, researchers have found, according to their computer model, that the increase in sea ice since 1970 in Antarctica cannot be explained by the ozone hole. (Note that the sea ice has been shrinking in the northern hemisphere while it has been growing in the south.) Key quote from paper:

It is presently unclear why the observed Southern Hemisphere sea ice extent trends are so different from those in the Northern Hemisphere. Previous studies have suggested that the cause might be related to atmospheric circulation changes induced by the stratospheric ozone hole. The results in this study are not consistent with this view and highlight the need for continued investigations of Antarctic sea ice extent trends.

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Avalanches on Mars

10:28 am

Saturday’s weekly dump of publications from the American Geophysical Union also included a paper that showed visual proof of avalanches on Mars! In this case, the location is Russell Crater, “a large crater in the southern hemisphere that exposes a large dune field in its center.” The avalanches occur because a frost layer made up of dry ice and a little bit of frozen water builds up on the crest of the dunes. When that frost melts, dark streaks about three to six feet wide and about 150 feet long appear, flowing downhill. The scientists believe these are avalanches made up of “a mixing of sand, dust, and unstable CO2 gas.”

wide shot of before and after
Before and after shots of the dark streaks flowing down the dune.

close-up, before and after
Close-ups of the streaks, before and after.

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