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Read through the most famous quotes by topic #astronomy
All the seeds of Christianity -- of superstition, were sown in my mind and cultivated with great diligence and care. All that time I knew nothing of any science -- nothing about the other side -- nothing of the objections that had been urged against the blessed Scriptures, or against the perfect Congregational creed. Of course I had heard the ministers speak of blasphemers, of infidel wretches, of scoffers who laughed at holy things. They did not answer their arguments, but they tore their characters into shreds and demonstrated by the fury of assertion that they had done the Devil's work. And yet in spite of all I heard -- of all I read. I could not quite believe. My brain and heart said No. For a time I left the dreams, the insanities, the illusions and delusions, the nightmares of theology. I studied astronomy, just a little -- I examined maps of the heavens -- learned the names of some of the constellations -- of some of the stars -- found something of their size and the velocity with which they wheeled in their orbits -- obtained a faint conception of astronomical spaces -- found that some of the known stars were so far away in the depths of space that their light, traveling at the rate of nearly two hundred thousand miles a second, required many years to reach this little world -- found that, compared with the great stars, our earth was but a grain of sand -- an atom – found that the old belief that all the hosts of heaven had been created for the benefit of man, was infinitely absurd. ↗
Let's grant that the stars are scattered through space, hither and yon. But how hither, and how yon? To the unaided eye the brightest stars are more than a hundred times brighter than the dimmest. So the dim ones are obviously a hundred times farther away from Earth, aren't they? Nope. That simple argument boldly assumes that all stars are intrinsically equally luminous, automatically making the near ones brighter than the far ones. Stars, however, come in a staggering range of luminosities, spanning ten orders of magnitude ten powers of ten. So the brightest stars are not necessarily the ones closest to Earth. In fact, most of the stars you see in the night sky are of the highly luminous variety, and they lie extraordinarily far away. If most of the stars we see are highly luminous, then surely those stars are common throughout the galaxy. Nope again. High-luminosity stars are the rarest. In any given volume of space, they're outnumbered by the low-luminosity stars a thousand to one. It's the prodigious energy output of high-luminosity stars that enables you to see them across such large volumes of space. ↗
He insisted that stars were people so well loved, they were traced in constellations, to live forever ↗
The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small. ↗
Before we invented civilization our ancestors lived mainly in the open out under the sky. Before we devised artificial lights and atmospheric pollution and modern forms of nocturnal entertainment we watched the stars. There were practical calendar reasons of course but there was more to it than that. Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away. ↗
