A few bits of astronomical news seem worth repeating here on BLDGBLOG:
1) Weather has been observed on the surface of a star for the first time. Astronomers have now seen “mercury clouds” moving through the turbulent skies of “a star called Alpha Andromedae.”
[Image: Weather on a star; via New Scientist].
Because the star does not have a magnetic field, however, scientists have been left scratching their heads over what causes the clouds to form; for the time being, then, no one really knows where these things come from.
I wonder, though, how far this “weather” metaphor really goes: are there storms, and hurricanes, and tornadoes? Is there actual convection up there, in the outer atmosphere of Alpha Andromedae, and, if so, is there ever precipitation – frozen mercury snowing down toward the star’s core on slow currents of helium gas?
While we’re on the subject, I’m also curious if there are any religious systems that use “hurricanes of mercury” as a kind of divine threat. You will be struck down by a hurricane of mercury…
After all, aren’t Mormons worried about being consumed by “hurricanes of fire”?
In which case a hurricane of, say, argon – or a tornado of germanium – isn’t all that much of a stretch.
Or perhaps a hurricane of transition metals could come blowing in over the islands of Stockholm, coating that city in a smooth new shell of mineralogical forms…
2) Meanwhile, some stars are apparently plated in gold.
“Scattered through space,” we read, “are some peculiar stars that seem to contain more gold, mercury and platinum than ordinary stars such as our Sun.”
These stars are referred to as being “chemically peculiar.”
[Image: Star Cluster R136, photographed by NASA, et. al.].
One star, in particular, which astronomers have named “chi Lupi,” has 100,000 times as much mercury as the Sun, and 10,000 times as much gold, platinum, and thallium.
What’s really, really cool about this, though, is that chi Lupi can apparently be thought of as a series of concentric shells, where each shell consists primarily of one element; the locations of these shells are determined by the atomic weights of the elements they contain.
In other words, “the heavy metals in the star were pushed outwards by the radiation pressure of the star’s ultraviolet light, but were kept from escaping by gravity.” On chi Lupi, for instance, there is a shell of mercury in the “stellar photosphere.”
Thin outer layers of gold can thus be found on this and other “chemically peculiar” stars throughout the universe.
[Image: The Cat’s Eye nebula, photographed by NASA, et. al.].
3) Finally, we’ve all heard about things like this before, but “one of the largest and most luminous stars in our galaxy” is also “a surprisingly prolific building site for complex molecules important to life on Earth.”
The discovery furthers an ongoing shift in astronomers’ perceptions of where such molecules can form, and where to set the starting line for the chain of events that leads from raw atoms to true biology.
That “true biology” can be tracked back to the stars is nothing new; but the fact that a star called VY Canis Majoris – “a red hypergiant star estimated to be 25 times the Sun’s mass and nearly half a million times the Sun’s brightness” – is burning with pre-biotic compounds, “including hydrogen cyanide (HCN), silicon monoxide (SiO), sodium chloride (NaCl) and a molecule, PN, in which a phosphorus atom and a nitrogen atom are bound together,” is apparently reason to get excited.
First, let me quickly say that I love – love! – the idea that biologists might someday study stars in their quest to understand the chemical origins of molecular biology; and, second, I’m curious if we could combine these three articles – asking: could storms of living matter form on the outer surface of a star, reaching hurricane strength as they blow in whorls and vortical currents across gold-plated skies?
The first astronomer to discover a living storm should win some sort of prize, I think.
[Image: The Carina Nebula, via NASA’s awesomely fun Astronomy Picture of the Day
In any case:
Even simple phosphorus-bearing molecules such as PN are of interest to astrobiologists because phosphorus is relatively rare in the universe – yet it is necessary for constructing both DNA and RNA molecules, as well as ATP, the key molecule in cellular metabolism.
These chemicals “can later find their way into newborn solar systems” – although it had been thought that “any molecules that condensed from the cooling, expelled gas would later be destroyed by the intense ultraviolet radiation emitted by the star.”
An expanding star, it was thought, like something out of the Greek myths, thus sterilized its progeny.
But there’s good news for we living creatures: the “ejected material” that later seeds fledgling solar systems with prebiotic compounds also “contains clumps of dust particles that apparently shield the molecules and can shepherd them safely into interstellar space.”
Note the “shepherd” metaphor.
Anyway, this all seems to suggest “that the chemistry that leads to life may be more widespread in the universe and more robust than previous studies have suggested.”
These astrobiological studies will soon be helped along by a “high-altitude radio interferometer, consisting of 50 dishes – each 12 metres wide – currently under construction” in Chile’s Atacama Desert.
[Image: Another view of NGC 7000; I can’t find the origin of this photograph, unfortunately – but the minute I can credit this to the appropriate photographer or institution, I will do so!].