Astronomers find an invisible dwarf galaxy
Using dark matter data that suggested the existence of a faint dwarf galaxy 300,000 light years away on the other side of the Milky Way, astronomers have pinpointed its location by finding a tiny cluster of bright Cepheid variable stars, also located at that distance.
“These young stars are likely the signature of this predicted galaxy,” said Chakrabarti, assistant professor in RIT’s School of Physics and Astronomy. “They can’t be part of our galaxy because the disk of the Milky Way terminates at 48,000 light years.” Invisible particles known as dark matter make up 23 percent of the mass of the universe. The mysterious matter represents a fundamental problem in astronomy because it is not understood, Chakrabarti said.
This result is intriguing because it not only found a previously unknown dwarf galaxy orbiting the Milky Way, it also provides further evidence that dark matter, whatever it is, does exist. The dark matter of this unseen dwarf galaxy showed its gravitational effects on Milky Way stars, and when the astronomers looked at the right spot suggested by those effects, they found distant stars that had to belong to the invisible dwarf galaxy, proving it was there. This is comparable to finding Neptune and Pluto by analyzing their gravitational effects and then predicting their location in the sky.
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.
Conscious Choice 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.
Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.
Using dark matter data that suggested the existence of a faint dwarf galaxy 300,000 light years away on the other side of the Milky Way, astronomers have pinpointed its location by finding a tiny cluster of bright Cepheid variable stars, also located at that distance.
“These young stars are likely the signature of this predicted galaxy,” said Chakrabarti, assistant professor in RIT’s School of Physics and Astronomy. “They can’t be part of our galaxy because the disk of the Milky Way terminates at 48,000 light years.” Invisible particles known as dark matter make up 23 percent of the mass of the universe. The mysterious matter represents a fundamental problem in astronomy because it is not understood, Chakrabarti said.
This result is intriguing because it not only found a previously unknown dwarf galaxy orbiting the Milky Way, it also provides further evidence that dark matter, whatever it is, does exist. The dark matter of this unseen dwarf galaxy showed its gravitational effects on Milky Way stars, and when the astronomers looked at the right spot suggested by those effects, they found distant stars that had to belong to the invisible dwarf galaxy, proving it was there. This is comparable to finding Neptune and Pluto by analyzing their gravitational effects and then predicting their location in the sky.
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.
Conscious Choice 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.
Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.
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