A complete survey of nearby sunlike starsA very long (182 pages) and detailed preprint paper was published today on the Los Alamos astro-ph website, describing the completion of a survey of just about all the sunlike stars within approximately 82 light years of the Earth. I haven’t had time to read the whole thing, but the abstract made these notable points:
- The study found that more the fifty percent of all sunlike stars are single stars.
- Among double and triple systems, the bell curve for the orbital periods peaked at 300 years.
- The more heavy elements the star has (atoms more complex than hydrogen and helium), the more likely it will have planets.
- The very intriguing conclusion: “The fraction of planet hosts among single, binary, and multiple systems are statistically indistinguishable, suggesting that planets are as likely to form around single stars as they are around components of binary or multiple systems with sufficiently wide separations. This, along with the preference of long orbital periods among stellar systems, increases the space around stars conducive for planet formation, and perhaps life.” [You need to download the full pdf to see this quote in the unabridged abstract.]
In other words, the evidence continues to suggest that solar systems like ours are very common.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
A very long (182 pages) and detailed preprint paper was published today on the Los Alamos astro-ph website, describing the completion of a survey of just about all the sunlike stars within approximately 82 light years of the Earth. I haven’t had time to read the whole thing, but the abstract made these notable points:
- The study found that more the fifty percent of all sunlike stars are single stars.
- Among double and triple systems, the bell curve for the orbital periods peaked at 300 years.
- The more heavy elements the star has (atoms more complex than hydrogen and helium), the more likely it will have planets.
- The very intriguing conclusion: “The fraction of planet hosts among single, binary, and multiple systems are statistically indistinguishable, suggesting that planets are as likely to form around single stars as they are around components of binary or multiple systems with sufficiently wide separations. This, along with the preference of long orbital periods among stellar systems, increases the space around stars conducive for planet formation, and perhaps life.” [You need to download the full pdf to see this quote in the unabridged abstract.]
In other words, the evidence continues to suggest that solar systems like ours are very common.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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