Dark Matter Getting Cloudy

New study finds mysterious lack of dark matter in Sun's neighborhood. FROM phys.org

"(Phys.org) -- The most accurate study so far of the motions of stars in the Milky Way has found no evidence for dark matter in a large volume around the Sun. According to widely accepted theories, the solar neighbourhood was expected to be filled with dark matter, a mysterious invisible substance that can only be detected indirectly by the gravitational force it exerts. But a new study by a team of astronomers in Chile has found that these theories just do not fit the observational facts. This may mean that attempts to directly detect dark matter particles on Earth are unlikely to be successful."

The stellar source of the elements that compose us

From Scientific American blogs: a fair use excerpt:

One of the most widely known and repeated astrophysical facts is that stars produce all the heavy elements that eventually make planets, shrubberies, and the likes of us. It’s absolutely true, but how exactly do they get those elements out into the universe to do all that?....

The problem is that we haven’t fully understood how stars perform this trick [of dispersing the elements]. The only tool they have at their disposal is the pressure of stellar photons – light flooding from the star can push and accelerate material away from it. However, getting this light to push against the gas of the stellar atmosphere efficiently enough to set it in motion has seemed difficult. One option is that the tiny grains of dust act like miniature solar sails, that in turn snowplough through the gas to accelerate it along in front of them. However this theory has had some gaps in it; figuring out the necessary combination of dust grain composition, size, and location of formation has been tricky....

We link to an illuminating answer above.

In the 1960s the US creates an successful artificial ionosphere

1960s -- US creates successful artificial ionosphere

Unidentifiable spectral lines

Following is an excerpt from an article on recent research done of relevance to star formation:

The colors of the universe

"If you point a telescope to the sky, you see spectral lines that are very specific to a certain molecule or atom," said Pavanello. Different moleculesemit photons at different wavelengths, which result in different spectral lines that allow astronomers to determine the chemical composition of stars. But the more these telescopes get accurate and precise, the more spectral lines we see."

"We are at a point in which we see many, many more spectral lines than we can possibly identify, and we don't know what these lines mean," said Pavanello.

Knowing the vibrational levels, and therefore the spectral lines of H3+, will allow astronomers and astro-chemists to sift through the inundation of spectral lines and further identify the elemental composition of objects in space.