The uncertainty of science: Astronomers have discovered 19 more dwarf galaxies, now totaling 23, that appear to have significant deficits of dark matter.
Of 324 dwarf galaxies analyzed, 19 appear to be missing similarly large stores of dark matter. Those 19 are all within about 500 million light-years of Earth, and five are in or near other groups of galaxies. In those cases, the researchers note, perhaps their galactic neighbors have somehow siphoned off their dark matter. But the remaining 14 are far from other galaxies. Either these oddballs were born different, or some internal machinations such as exploding stars have upset their balance of dark matter and everyday matter, or baryons.
It may not be a case of missing dark matter, says James Bullock, an astrophysicist at the University of California, Irvine. Instead, maybe these dwarf galaxies have clung to their normal matter — or even stolen some — and so “have too many baryons.” Either way, he says, “this is telling us something about the diversity of galaxy formation…. Exactly what that’s telling us, that’s the trick.”
Since we do not know what dark matter is to begin with, finding galaxies lacking it only makes more difficult to create a theory to explain it. Something causes most galaxies to rotate faster than they should, based on their visible mass. What that is remains an unknown.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space
, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.
Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95; Shipping cost for either: $5.00). Just email me at zimmerman @ nasw dot org.