kkokkolis

Rockets Through Space: The Story of Man's Preparations to Explore the Universe, Lester Del Rey, James Heugh, 1957

Rockets Through Space: The Story of Man's Preparations to Explore the Universe, Lester Del Rey, James Heugh, 1957

Rockets Through Space: The Story of Man's Preparations to Explore the Universe, Lester Del Rey, James Heugh, 1957

Rockets Through Space: The Story of Man's Preparations to Explore the Universe, Lester Del Rey, James Heugh, 1957

Δυστυχώς η Celestron διέκοψε την προσφορά του θωρακισμένου υδατοστεγούς spotting scope C90 (υπάρχει ακόμη stock) αλλά εξακολουθεί να προσφέρει την απλή έκδοση σε εξωφρενική τιμή.

Μετά την διθυραμβική κριτική των C6 και C8 από τον Ed Ting μία μεγάλη έκπληξη: Ενδελεχής σύγκριση τριών Mak 90mm, του ονειρικού Questar 3'', του Volksteleskop Meade ETX 90 και του ταπεινού Celestron C90. Αποκαθήλωση των ειδώλων. http://www.scopereviews.com/90mmComparo.html Από σήμερα θα φέρομαι στο C4 με ακόμη μεγαλύτερο σεβασμό! Bresser AltAz της πλάκας με 4 περικάρπια. περιτάρσια βάρη του μισού κιλού, το ξεκούρδιστο μανταρίνι C4 με 2'' διηλεκτρικό διαγώνιο, ένας ES100 9mm, ένα κάθισμα σιδερώματος και Σελήνη/ Κρόνος, είναι η νέα μου μανία.

Αναδύονται αρκετά ερωτήματα μεταμφιεσμένα σε απαντήσεις. Εξ αυτών αποδίδω τα πρωτεία στο άνωθεν επιπολάζον: Μήπως κάποτε δεν μας αρέσει αυτό που βλέπουμε σαν στρέφουμε το βλέμμα προς τα κάτω;

Celestial, model Ref 5106, Patek Philippe, 2009

Astronomy, John Rush

Hertzprung-Russell diagram, Nerd Art, Electricboogaloo

Παράλλαξη, Copperleaf Studios, 2010 Όλα τα χαρακτικά σε μπρούτζο και τσίγκο.

Σελήνη, Copperleaf Studios, 2010

Luna, Copperleaf Studios, 2010

Βαρύτητα, Copperleaf Studios, 2010

Έκλειψη, Copperleaf Studios, 2010

Πτολεμαϊκό Σύστημα, Copperleaf Studios, 2010

De Motis Stelle Martis, Copperleaf Studios, 2010

Αστρονομική Συσκευή, Copperleaf Studios, 2010

Voyager 2, Copperleaf Studios, 2010

Αστρονομικά Όργανα, Copperleaf Studios, 2010

Ουράνια Σφαίρα, Copperleaf Studios, 2010

This too shall pass, psnt.net (positive science | negative theology), Paul Wallace, Jun 07 2010 During my last few years as an astronomy professor, I started off the first day by walking to the front of the class and writing the following on the board: ASTRONOMY IS A WASTE OF TIME. I then ask: Why might this be true? The idea is to short-circuit some of their inevitable concerns up front, to adjust their expectations, and to motivate them. Once they see that I’m serious the students relax a little and the conversation begins to flow. A common answer is: Astronomy is useless. This is true. Not that it is not wholly without use; our understanding of the Sun’s workings and of the orbits of near-Earth asteroids may one day be most helpful. Astronomy was once very useful for navigation, hence trade. Also for calendry and for certain religious purposes like setting the date for Easter. Routine uses of astronomy today tend to be highly specialized and have to do largely with ultra-precise reckoning of time. So it has its utility. But only a fraction of astronomy is concerned with the Sun or the orbital dynamics of bodies housed within the inner Solar System, and even within that fence much is clearly impractical. Astronomical science is almost wholly occupied with stuff that has no pragmatic bearing whatsoever: Saturn’s auroras, galactic evolution, quasars, cosmology. Arguments like No one foresaw the uses of the laser are familiar. And it is true that we cannot know now what we will need to know in the future. But if one were to order the sciences using any conceivable measure of usefulness, astronomy would come in at the bottom with plenty of daylight between it and the rest of the pack. There have been other predictable answers, such as: Astronomy is expensive. This is also true. American astronomy is funded through two pipes: NASA and the NSF. For a good time, browse the 2011 NASA Science Mission Directorate and 2010 NSF astronomy budgets. You’ll get the idea. These two answers were expected. But there was another popular answer that I was wholly unprepared for: Astronomy is depressing. Usually what the student had in mind is that we’re small compared to the cosmos. This is true. To say that the Earth is a drop in the ocean of space is so frantically understated as to be laughable. We would need to compare a single drop of water to 10^30 Pacific Oceans to get a decent comparison. (The number 10^30 is the same as the number 1 followed by 30 zeros.) And this takes into account only the visible universe. We have good reasons to suspect that there’s much more of it that we can’t see, that we will never be able to see. What students are generally less aware of is that things appear to be winding down. The Sun is not immortal. It will die in a few billion years, and when it does the Earth will be cooked, its life extinguished and its oceans vaporized. Who knows where we will be by then. It seems unlikely that we will make it that far, because we have a lot more to cope with than ourselves and our toxic combination of violent tendencies and nightmarish weapons. Catastrophic meteorite impacts await us in the next million years, to say nothing of the next billion. Also dramatic climate changes. If we make it through and leave the Solar System behind before the Sun’s final gasp, we will no longer appear human by today’s standard. The pressures of evolution and biotechnology will see to that. But even if we make it we won’t make it, because the universe itself is dying. Currently astronomers think it’s headed for the ultimate freezeout. In this scenario the entire cosmos will continue in its current expansion into an infinite future, its ambient temperature on a one-way descent toward absolute zero, its dynamism lost in a total washout of physical structure. There are other possibilities, but all of them lead to a single conclusion: Humanity will not prevail against nature. Thus I concede, at least partially. Astronomy can be depressing. But you know what? It’s just a reminder of what everyone already knows but doesn’t want to know: This too shall pass. This fact of life occurred to me first when I was about twelve. Carl Sagan‘s Cosmos had just been published and Dad had a copy. In it was a series of four paintings of a single locale. The first one was edenic: A bright array of living things grew alongside an expanse of incandescent blue water. The scene was lit by a perfectly yellow sun. As the series progressed the sun became orange and bloated enormously. Life disappeared and the ocean with it. In the end the blooming prospect was reduced to a wasteland ruled over by a hideous red orb. Here is the caption. I read it over and over. The death of the Earth and Sun. Several billion years from now, there will be a last perfect day. Then, over a period of millions of years, the Sun will swell, the Earth will heat, many lifeforms will be extinguished, and the shoreline will retreat. The oceans will rapidly evaporate and the atmosphere will escape to space. As the Sun evolves toward a red giant, the Earth will become dry, barren, and airless. Eventually the Sun will fill most of the sky, and may engulf the Earth. Clearly death awaited the world. A last perfect day. The words alarmed me. But I also felt the pull of a strange curiosity. Billions of years. No one I knew would be alive. But I looked around and tried to set the particulars of my environment into relation with the coming apocalypse. Even then the interstate freeways around Atlanta were crowded with cars, and I wondered when and under what circumstances those roads would be emptied. At the time the seventy-two-story Westin Peachtree Plaza was the city’s tallest building. To me it was monumental. I had watched it rise. When would it fall? Would it stand until the Sun melted it? One day it occurred to me with supreme force that, as a fact, my family’s house would crumble eventually. I stood outside with my nose three inches from the wall and wondered when the bricks, those bricks right there, would be separated from one another. Because, as a fact, they would be. On what exact calendar date? What would the weather be like on that day? Would there be clouds? If so, what would their configuration be at the precise moment of separation? Heavy thoughts for a 12-year-old, maybe, but it’s real and we spend a lot of time avoiding the fact that things — all things — fall apart. Pragmatists ever, the Buddhists are keenly aware of this and even have a special word — anicca — to express this fact of life. It is one of the three interrelated marks of existence, the other two being dukkha and anatta. Dukkha refers to suffering. Indeed, suffering is a fact. I don’t think I need to convince anyone of this. Anatta, or “not-self,” refers to the idea that there there is no permanent self, that all phenomena — the earth, the sun, trees, ourselves — possess no true, everlasting essence. It is for that reason that we should not cling to anything: not material goods, not status, not nature, not education, not even life itself. My New Testament professor, Luke Timothy Johnson, once said that of all major religions he preferred Christainity and Buddhism because only these two displayed an appropriate level of cynicism regarding our human station. I laughed when he said that but I wrote it down in the margin of my notes, thinking: I need to remember this. What happens when one really embraces one’s impermanence? Does one commit suicide? Does one come to understand Jesus? Does one wake up? Or does one, to paraphrase Walker Percy, live happily ever after precisely because one does not have to?

Artes Liberales, Astronomia et Ptolemaeus, 15ος αιώνας Unibibliotek Salzburg

Leica Aspheric Zoom 25x-50x, 18-9mm, 60-80 degree

Leica Zoom APO Televid WW ASPH Eyepiece 25-50x82mm