Data from Messenger now shows that as Mercury cooled it shrunk far more than earlier data had indicated.

Data from Messenger now shows that as Mercury cooled it shrunk far more than earlier data had indicated.

A new census of these ridges, called lobate scarps, has found more of them, with steeper faces, than ever before. The discovery suggests that Mercury shrank by far more than the previous estimate of 2-3 kilometres, says Paul Byrne, a planetary scientist at the Carnegie Institution for Science in Washington DC. He presented the results today at a meeting of the American Geophysical Union in San Francisco, California.

The finding helps explain how Mercury’s huge metallic core cooled off over time. It may also finally reconcile theoretical scientists, who had predicted a lot of shrinkage, with observers who had not found evidence of that โ€” until now. โ€œWe are resolving a four-decades-old conflict here,โ€ Byrne told the meeting.

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An upbeat wimpy maximum holds on

Today NOAA posted its monthly update of the solar cycle, showing the sunspot activity for the Sun in November. As I do every month, I am posting it here, below the fold, with annotations.

As in October, the Sun was more active than it has been for this entire solar maximum. November’s numbers dropped slightly from October, but still remained high, though as has been typical for this solar maximum they remained below prediction.
» Read more

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Curiosity has succeeded in dating the age of one of its rock samples, the first time this has ever been done remotely on another planet.

Curiosity has succeeded in dating the age of one of its rock samples, the first time this has ever been done remotely on another planet.

The second rock Curiosity drilled for a sample on Mars, which scientists nicknamed “Cumberland,” is the first ever to be dated from an analysis of its mineral ingredients while it sits on another planet. A report by Kenneth Farley of the California Institute of Technology in Pasadena, and co-authors, estimates the age of Cumberland at 3.86 billion to 4.56 billion years old. This is in the range of earlier estimates for rocks in Gale Crater, where Curiosity is working.

This is significant engineering and scientific news. In the past the only way to date the rocks on another world was to bring them back to Earth. This was how the moon’s geology was dated. On Mars, dating has only been done by crater counting, comparing those counts with those on the Moon, and then making a vague guess. To have the ability to date rocks remotely means that geologists can begin to sort out the timeline of Mars’s geology without having to bring back samples.

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Using Solar Dynamics Observatory (SDO), scientists have finally identified the Sun’s predicted giant jet streams.

Using Solar Dynamics Observatory (SDO), scientists have finally identified the Sun’s predicted giant jet streams.

These large flows, bigger than any flow structures previously identified, might help explain the Sun’s rotation (which is faster at the equator than at the poles), its magnetic field, and its production of sunspots. Not surprisingly, however, the models and data do not match exactly:

Mark Miesch, a physicist at the National Center for Atmospheric Research in Boulder, Colorado, says the new study confirms modelling work he and others have done on giant convective cells4. There are, however, some differences between what the models suggest and what Hathawayโ€™s team observed. For instance, the models indicate that giant cells should align themselves from north to south near the Sun’s equator, an arrangement that isnโ€™t seen in the new data. In fact, points out solar physicist Junwei Zhao of Stanford University in California, most of the giant cells were seen at high latitudes, and they need to be spotted at lower latitudes as well. โ€œWhether it will convince the community remains to be seen,โ€ says Zhao.

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The head of India’s research team at its Antarctica base has been recalled after he ordered the shut down of power at the station.

Welcome to the movies: The head of India’s research team at its Antarctica base has been recalled after he ordered the shut down of power at the station.

From October 7 to 12, ISRO’s satellite ground station at Antarctica, lost all transmission when its power supply was allegedly shut down by the team leader of the 32nd winter expedition to Bharati. The scientist, whose name was not revealed, has since been suspended and brought back to Goa. On October 14, NCAOR had also filed a police complaint against the scientist for the ‘wanton act of shutting down power’, said a statement released by the Ministry of Earth Sciences on Saturday.

This story had this tidbit:

It is believed the probe was ordered after the team leader allegedly ordered for the stationโ€™s power supply, which is obtained from diesel generators, to be cut off. A former chairman of ISRO, on the condition of anonymity, said: โ€œIf shortage of fuel was the issue, why would the ISRO station not take stock of fuel two months before it was to get exhausted and make arrangements for additional supply from South Africa? It is the most obvious thing to do. Unless there is some confusion or some issues, such a thing in Antarctica is unheard of. If power is switched off, people inside will freeze. So why was the power ordered to be cut off and why wait for diesel to get over?โ€

It also appears that three people are involved in this story, though details remain scant.

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Here’s another report on the planetary sciences/NASA dispute this week over funding and grant scheduling.

Here’s another report on the planetary sciences/NASA dispute this week over funding and grant scheduling.

From this report it appears that the complaints by the planetary science community might have been a bit overstated. It doesn’t appear that NASA is cutting the planetary sciences grant program in any significant way.

I suspect that the reason the planetary scientists are so touchy is because they do not trust the Obama administration, based on its previous efforts to eliminate the planetary program entirely. (It is also possible that they are right.)

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