Author: Robert Zimmerman

ESA controllers buy time to solve problems on comet probe Rosetta

11:03 pm

This ain’t good. One of the reasons ESA controllers recently put the comet probe Rosetta into hibernation for two and a half years was in order to buy time to solve a serious technical problem.

Mission managers said the hibernation will permit Rosetta to rest its four reaction wheels, two of which have shown signs of degradation. The satellite needs three to function, and one of the two problem wheels will be used only as a spare when the satellite is awakened in January 2014 in preparation for its approach to a comet.

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Second X-51 hypersonic flight crashes prematurely

10:53 pm

Second X-51 hypersonic flight crashes prematurely.

After what the US Air Force described as a ‘flawless’ flight to the launch point aboard a Boeing B-52 mothership, the X-51 was successfully boosted to Mach 5.0 by a rocket booster. The Pratt & Whitney Rocketdyne scramjet engine successfully ignited using its initial fuel, ethylene. During the immediate transition to JP-7, the conventional fuel that makes the X-51 unique, an inlet unstart occurred. A subsequent attempt to restart and reorient to optimal conditions was unsuccessful.

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An X-ray deep field over six weeks by Chandra finds massive black holes common in early universe

1:29 pm

An X-ray deep field image taken over a six week period by Chandra had found that massive black holes are common in early universe.

These results imply that between 30% and 100% of the distant galaxies contain growing supermassive black holes. Extrapolating these results from the relatively small field of view that was observed to the full sky, there are at least 30 million supermassive black holes in the early Universe. This is a factor of 10,000 larger than the estimated number of quasars in the early Universe.

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The progenitor of the May supernova in M51 identified

10:08 am

supernova 2011dh before it exploded

The progenitor star that produced the May supernovae in the Whirlpool Galaxy (also known as M51) has been identified, and it isn’t what scientists predicted.

In a preprint paper published today on the Los Alamos astro-ph website, astronomers describe the star that exploded as a yellow supergiant, not a red supergiant or Wolf-Rayet star, as predicted by the theory explaining this particular type of supernova. Moreover, though theory also favors the star being a member of a binary system, the progenitor of 2011dh appears to be a lone star, not even a member of a cluster.
» Read more

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Solar scientists predict a major decline in sunspot activity

1:37 pm

At a press conference today at the 2011 meeting of the Solar Physics Division (SPD) of the American Astronomical Society (AAS) in Las Cruces, New Mexico, solar scientists predicted that not only will the next solar maximum in 2013 be the weakest in centuries, it is very likely that it will be followed by another long Maunder Minimum, a period of decades without sunspots. “The sun may be going into hiatus,” says Dr. Frank Hill, associate director of the NSO’s Solar Synoptic Network. You can read the press releases for this announcement here and here.

decline in magnetic field over the last few cycles

These conclusions are based on three lines of evidence:

  • There has been a long term weakening in the magnetic strength that produces sunspots themselves. The declining trend suggests that by 2022 it will no longer be strong enough to produce sunspots. The graph above shows this decline.
    » Read more
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Obamacare doesn’t stop Medigap providers, AARP partners from discriminating against seniors

11:31 am

Surprise, surprise! Obamacare doesn’t stop Medigap providers and AARP from discriminating against seniors with preexisting conditions, as had been promised.

This story is just more evidence that the law is a mess, it should never have been passed, and in the future our so-called lawmakers should read the goddamn legislation before they vote on it.

I should add that I think it a very big mistake for the government to forbid insurance companies from denying new coverage to sick individuals. If insurance companies are forced to accept everyone as a new customer, even those who are ill, why bother paying for insurance when you are healthy? Everyone can simply wait until they are sick, and then buy the coverage, thereby getting a lot of insurance for very little investment. The result: insurance companies go bankrupt, as the whole concept of insurance depends on a lot of healthy customers paying the cost, at a low rate, for those who are sick.

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Robot refueling test of satellites to be launched on last shuttle flight

10:09 pm

A testbed for testing the robotic refueling of satellites will be installed on ISS on last shuttle flight.

This whole testbed is the brainchild of Frank Cepollina, the man behind all of the Hubble Space Telescope repair missions. Until recently it was doubtful there was room for this project on any shuttle mission. That he nonetheless managed to get it on the last flight is another testament to Cepollina’s incredible ability to get things done. And if the tests work on ISS, NASA will then consider launching operational systems for refueling several perfectly usable climate satellites now in orbit.

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