One astronomer has found that the habitable zone around some smaller stars is smaller than first calculated because of tidal heating.

One astronomer has found that the inner edge of the habitable zone around some dwarf stars is smaller than first calculated because tidal forces overheat planets close to the star.

Then again, this heating might expand the habitable zone in other directions. Stars might overheat when close to the star, but get a boost of needed heat when they would normally be too far away.

Richard Rogers – Edelweiss

An evening pause: From The Sound of Music (1965). The context: The Nazis have taken over Austria, and plan to arrest Captain Georg Ludwig von Trapp and his family at the end of this concert. This lovely song, Edelweiss, is initially sung by von Trapp as a farewell to his nation. As the song unfolds, however, it becomes instead a song of defiance against the Nazis, by the von Trapps and the audience.

Always, always, we must stand for freedom.

Astronomers now believe that Type 1a supernovae — used to discover dark energy — can be produced in two different ways.

The uncertainty of science: Astronomers now believe that Type 1a supernovae — used to discover dark energy — can be produced in two different ways.

Type Ia supernovae are known to originate from white dwarfs – the dense cores of dead stars. White dwarfs are also called degenerate stars because they’re supported by quantum degeneracy pressure. In the single-degenerate model for a supernova, a white dwarf gathers material from a companion star until it reaches a tipping point where a runaway nuclear reaction begins and the star explodes. In the double-degenerate model, two white dwarfs merge and explode. Single-degenerate systems should have gas from the companion star around the supernova, while the double-degenerate systems will lack that gas.

For astronomers, this possibility raises several conflicting questions. If two different causes produce Type 1a supernovae, could their measurement of dark energy be suspect? And if not, why is it that these two different causes produce supernovae explosions that look so much alike?

Massachusetts state officials are restricting the kinds of foods that can be sold at bake sales.

We’re here to help you: Massachusetts state officials are restricting the kinds of foods that can be sold at bake sales.

Bake sales, the calorie-laden standby cash-strapped classrooms, PTAs and booster clubs rely on, will be outlawed from public schools as of Aug. 1 as part of new no-nonsense nutrition standards, forcing fundraisers back to the blackboard to cook up alternative ways to raise money for kids.

Scientists have found that a solar Grand Minimum 2800 years ago might have caused a period of cooling in Europe

Scientists have found that a solar Grand Minimum 2800 years ago might have caused a period of cooling in Europe.

The evidence for this link is at this moment slim, based upon a single data point from a lake in Germany. Nonetheless, it is further evidence that the Sun’s production of sunspots is more important to global climate than climate scientists had previously believed.

A new study has found that the glaciers of Greenland are not behaving as predicted.

The uncertainty of science: A new study has found that the glaciers of Greenland are not behaving as predicted.

In northwestern Greenland, for example, where most of the glaciers move relatively quickly and flow directly into the sea rather than ending on land, average speed jumped by 8% between 2000 and 2005 and rose another 18% from 2005 to 2010. Nevertheless, the researchers report online today in Science, the glaciers in this region showed no uniform pattern of acceleration. About one-third flowed at the same rate throughout the decade, one-fourth slowed during the interval, and about 15% slowed during the first half of the decade and then surged from 2005 to 2010.

Similarly, many of the individual glaciers in southeastern Greenland don’t follow the region’s overall trend. Although the average speeds for these glaciers increased by 28% over the decade, substantial accelerations by some glaciers were balanced by considerable slowing by others. About 43% of the glaciers in the region sped up between 2000 and 2005, but around 25% slowed down by more than 15% from 2005 to 2010.

In other words, if there is any warming, it hasn’t manifested itself in a predictable manner in the glaciers of Greenland. In fact, the data above suggests instead that if there has been any warming, it either has been far less than predicted, or has had relatively little influence on the Greenland ice sheet.

Scientists have discovered that the half life of one of their key isotopes for dating the solar system is 30% shorter than previously believed.

The uncertainty of science: Scientists have discovered that the half life of one of their key isotopes for dating the age of the solar system is 30% shorter than previously believed.

The main result of the work of the international scientists, detailed in a recent article in Science, is a new determination of the half-life of 146Sm, previously adopted as 103 million years, to a much shorter value of 68 million years. The shorter half-life value, like a clock ticking faster, has the effect of shrinking the assessed chronology of events in the early solar system and in planetary differentiation into a shorter time span.

The new time scale, interestingly, is now consistent with a recent and precise dating made on a lunar rock and is in better agreement with the dating obtained with other chronometers. The measurement of the half-life of 146Sm, performed over several years by the collaborators, involved the use of the ATLAS particle accelerator at Argonne National Laboratory in Illinois.

A special issue from Nature: Peopling the planet.

A special issue from Nature: Peopling the planet.

I haven’t yet had time to read this special issue, but it will certainly be fascinating, as it apparently summarizes the most current knowledge scientists have about the manner and timing of the human migration of the entire surface of the Earth. Overall, it appears that this migration took place sooner and faster than previously believed. Definitely worth a read.

The Department of Energy has approved the start of detailed engineering for the Large Synoptic Survey Telescope.

Ground-based astronomy moves forward: The Department of Energy has approved the start of detailed engineering for the camera on the Large Synoptic Survey Telescope.

I have to admit, I am puzzled why the Department of Energy is involved in this. Government funding for ground-based telescopes normally comes from the National Science Foundation.

Europe has decided to build a probe, dubbed JUICE, to study Ganymede, Callisto and Europa, Jupiter’s big icy moons.

Europe has decided to build a probe to study Ganymede, Callisto and Europa, Jupiter’s big icy moons.

Known as JUICE, the Jupiter Icy Moons Explorer, the probe will enter orbit around the gas giant planet in 2030 for a series of flybys of Ganymede, Callisto and Europa. JUICE will brake into orbit around Ganymede, Jupiter’s largest moon, in 2032 for at least one year of close-up research.

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