An astonishing exploration of planet formation and the origins of life by one of the world’s most innovative planetary geologists. In 1959, the Soviet probe Luna 3 took the first photos of the far side of the moon. Even in their poor resolution, the images stunned scientists: the far side is an enormous mountainous expanse, not the vast lava-plains seen from Earth. Subsequent missions have confirmed this in much greater detail. How could this be, and what might it tell us about our own place in the universe? As it turns out, quite a lot. Fourteen billion years ago, the universe exploded into being, creating galaxies and stars. Planets formed out of the leftover dust and gas that coalesced into larger and larger bodies orbiting around each star. In a sort of heavenly survival of the fittest, planetary bodies smashed into each other until solar systems emerged. Curiously, instead of being relatively similar in terms of composition, the planets in our solar system, and the comets, asteroids, satellites and rings, are bewitchingly distinct. So, too, the halves of our moon. In When the Earth Had Two Moons, esteemed planetary geologist Erik Asphaug takes us on an exhilarating tour through the farthest reaches of time and our galaxy to find out why. Beautifully written and provocatively argued, When the Earth Had Two Moons is not only a mind-blowing astronomical tour but a profound inquiry into the nature of life here—and billions of miles from home.
An astronomer and author of the best-selling What If the Moon Didn't Exist explores ten examples of what Earth would be like if conditions in the universe were slightly altered, in a fascinating journey into scientific scenarios.
The planet Venus is the closest neighbour to the Earth and in several respects similar to our globe. It revolves around the Sun at an average distance of 0. 72 astronomical units, in an elliptical orbit of eccentricity 0. 007. The corresponding 3 numbers for the Earth are 1 and 0. 017. The mean density of Venus is 5. 2 g/cm , 3 that of the Earth 5. 5 g/cm . Venus’ acceleration of gravity at its equator is 8. 9 2 2 m/s , compared with 9. 8 m/s at the Earth. The escape velocity is 10. 4 km/s, while the corresponding ?gure of the Earth is 11. 2 km/s. Although the mass of Venus is somewhat smaller than that of the Earth – the ratio is M /M =0. 815 V E – the diameters of the two planets are almost the same. In other words, Venus is indeed a sister planet of the Earth. In earlier times, when almost nothing was known about the physical con- tions of Venus, the similarity appeared even stronger than today. Not only was Venus’ period of rotation thought to be close to that of the Earth, it was also p- sible (and indeed common) to imagine intelligent life on Venus.
After escaping capture by government agents and fleeing to the Homeworld, the Tennisons are returning to Earth. But before they can return to a normal life they must complete a rescue mission. A mission which will split the family across two worlds and decide the fate of Earth.
Real Dreams: Thirty Years of Short Stories is a collection of 15 short stories written between 1981 and 2011. The stories are from multiple genres with some common themes, including hope, dreams, light, darkness, perseverance, and spirituality, wrapped up in some novel ideas. Enjoy these diverse and timeless works three decades in the making.
In this engaging and accessible exploratory work, accomplished astrophysicist Neil F. Comins shows how ten hypothetical astronomical situations would affect our planet and life on it. What if the Moon didn't exist, for example? The Earth would be rotating much faster than it presently does, tides would be lower, and life would be much more primitive than it is today. "What if the Moon Didn't Exist?" has been made into TV, radio, planetarium, and theater shows, and became the theme to Mitsubishi's pavilion at the World Expo in Nagoya, Japan in 2005. Praise for What if the Moon Didn't Exist ..".a new genre...Seductively cunning...All these "what-ifs" have the cumulative effect of making us excruciatingly aware of what a special and precarious place we inhabit - and how easy it would have been for it to be otherwise." -The Washington Post "Imaginative and stimulating." -Booklist "Comins's scientific expertise is dizzying. It takes a rare writer to manipulate so many unknown factors with such ease and convincing detail. This book will thrill everyone who can't help wondering "what if..." -Astronomy Book Club
Fully updated throughout, including revised illustrations and new images from NASA missions, this new edition provides an overview of Earth's history from a planetary science perspective for Earth science undergraduates. Earth's evolution is described in the context of what we know about other planets and the cosmos at large, from the origin of the cosmos to the processes that shape planetary environments and from the origins of life to the inner workings of cells. Astronomy, Earth science, planetary science and astrobiology are integrated to give students the whole picture of how the Earth has come to its present state and an understanding of the relationship between key ideas in different fields. The book presents concepts in nontechnical language and mathematical treatments are avoided where possible. New end-of-chapter summaries and questions allow students to check their understanding and critical thinking is emphasized to encourage students to explore ideas scientifically for themselves.
The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.
The e-book ?Aliens, Ufo?s and Alien Technology? contains over 70,000 words of previously unpublished information about aliens.Giving three worked examples of alien technology, there is included a virtual scientific report on two methods of ' planet hopping?.Yes, people want to know more about aliens, how aliens think and of course their purpose here on earth, so be properly informed about this particular species of aliens.There are many types of aliens, some benevolent, but a few are malevolent.This book deals with 'Aliens of the worst kind', The Reptoids.As for this species of aliens, 'The Reptoids', you dont want to meet them,it would be better if you did not, it?s as simple as that.Should you meet 'them', you must know that there are no evasive tactics.'The Reptoids' regard this planet as 'theirs' and they are just waiting until our technology develops sufficiently before making their move.Once 'The Reptoids' have what they want, are we expendable?, or will we be rescued?.Whilst I could have used a series of Fact Sheets to convey the massive amount of information concerning this particular species of aliens, my book agent suggested that all this info be written into a story instead.Here is that story, shocking in places, scary in others, mankind will have to deal with these aliens one day and we will need to be the winners, or die trying to be.
An examination, published in 1862, of the relationship between the natural world and the supernatural, by a leading Scottish philosopher.
On February 19, 1973, five centuries have elapsed since the birth of Nicolaus Coperni cus - the greatest astronomer of the Renaissance period - who rediscovered for us the heliocentric model of the solar system, and documented it by his life's work in such a manner as to make its concept a permanent property of mankind. The life of Copernicus, extending from 19 February 1473 to his death on 24 May 1543, was not too rich in adventures or biographical facts. Born in Toruti from a family of Polish burghers, he received his first university training in Cracow between 1491-1494. From Cracow he proceeded to Italy to spend the years between 1496-1503 at the Universities of Bologna, Padua and Ferrara - with occasional visits to Rom- in preparation for an ecclesiastical career. When Bishop Watzenrode - his patron and maternal uncle - could no longer extend his leave, Copernicus returned to Poland in 1503 to enter the service of the church establishment, which soon led to a canonry at the Frombork (Frauenburg) Cathedral in Warmia. And there - in the northern mists not far from the Baltic shores - in a land so different in climate from the sunny Italy of his youth - he was destined to spend the rest of his life.
French astronomer Camille Flammarion (1842-1925) called the study of the heavens 'the science which concerns us most'. He believed that learning 'what place we occupy in the infinite' could delight and instruct, and might even promote an end to war and strife. Flammarion dedicated the present work to François Arago (1786-1853), author of earlier work on popular astronomy. Since Arago's time, the capabilities of telescopes and other instruments had vastly improved, advancing understanding in areas such as the composition of stars. Flammarion sought to bring this new knowledge to the public in a charming yet 'scrupulously exact' style. His highly illustrated introduction to astronomy succeeded in reaching a wide readership, selling over 100,000 French copies before this English translation appeared in 1894. The 1881 French version and Flammarion's work on the origins of the Earth, Le Monde avant la création de l'homme (1886), are also reissued in this series.