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Donald Trump demanded NASA land humans on the moon in 2024 and increased funding for the agency. But the deadline kept shifting to the right. Now even 2027 is in question - industry experts doubt Axiom's ability to create a spacesuit for lunar conditions. Donald Trump demanded NASA In parallel, Elon Musk said, “We will fly straight to Mars, the Moon is a distraction.” The billionaire's critics suggested that he was having trouble with the landing module and wanted to get out of the lunar project while saving face. And then the media also investigated that the new leadership of NASA plans to abandon the SLS rocket and the Orion spacecraft. That is, except for Musk, who gave up on the Moon, the agency will simply have no other carrier capable of delivering people to Earth's satellite. From the outside, the Artemis III lunar program looks like poorly managed chaos. Does this mean that landing on the moon won't happen in the next few years? Artemis III lunar program The photo below shows an astronaut on the moon during the Artemis III mission. The picture is not just an artist's fantasy - it shows the scope of ambition of the planners of the new mission. The spacesuits of the times of the first flights to Selene did not allow anything like this: it was unreal to bend legs at 90 degrees and stand in them, astronauts moved barely bending their legs, and sometimes even jumped. Now, mankind knows much more about the Moon and, in theory, should be capable of new achievements there. Including the exploration of the Moon's south pole, which is rich in ice and permafrost, and providing astronauts with fundamentally new technical means. Let's imagine that we have been invited to lead a long and complex project, the intricacies of which are sometimes not fully understood by the developers. After all, they were once called in to correct the faults of those who came before them. This is the situation with the project “Artemis III” - the return of astronauts to the moon in 2027 or later. The current solutions to the project seem like a dead end. But what went wrong, and how might events unfold? Artemis problems before Trump The Constellation project was launched in 2005 with the goal of “returning to the Moon no later than 2020”. 15 years seemed to be a sufficient period at the time: the previous lunar project in 1961-1969 was half as long. And this on “grandfather hardware” and software. Constellation project Then, twenty years ago, NASA expected to fly to the Moon, land, and return completely independently, as under von Braun, giving contractors the general technical appearance of the product and controlling the way they build it. There are four key components in the lunar programs: Super-heavy launch vehicle
Spacecraft
Landing module
Spacesuit Super-heavy launch vehicle Spacecraft Landing module Spacesuit It would seem that success is inevitable. After all, the program planners initially reported that in order to save time and money as much as possible, they use the engines left over from the Space Shuttle program. After four years, it became clear: overruns on the development are so great that without a sharp increase in the total costs of the program, it is unrealizable. It was canceled, but NASA did not give up and rebranded the super-heavy rocket for the moon “Ares” in SLS. The ship Orion was not renamed. There was a minimum of changes in the project, and the lunar landing module Altair was postponed until better times. “Best times” for a return to the Moon developed during Trump's first term: in 2018, he finally sanctioned the Artemis program for this purpose. But by the early 2020s, it became clear that finishing all four components of the lunar program in-house was utopian for the agency. The finalization of SLS and Orion rockets was already in the second decade, and the final was not seen. NASA has not succeeded in developing a spacesuit at all. It was risky to start a module under such conditions. developing a spacesuit Then, the agency decided to get rid of criticism for punctures in the development and make it a future target of private developers. The lunar landing module was entrusted to SpaceX - in fact, it turned out to be a Starship with landing legs. Two private companies were hired to make spacesuits: Collins and Axiom. The extravehicular spacesuits have not worked out so well so far. Collins simply withdrew from development, saying that it is too complex a task. And Axiom, even at public shows, demonstrated the models being created without life support systems. In addition, at one of the latest shows, people saw a clone of a prototype NASA spacesuit from 2019, but with colored design inserts from Prada. By the way, there will almost certainly be no large inserts in the real lunar landing for technical reasons. As if spacesuits weren't enough! The situation has been simultaneously exacerbated by both Musk and his political opponents. Seth Abramson, for example, thinks the latter has lost his mind. By the way, he calls himself “Ilon Musk's biographer,” although the existing biography was actually created by Walter Isaacson. Anyway, on January 7, Abramson suggested that the Biden administration break all contracts with Ilon and begin prosecution. Except that without contracts with Musk, not only Artemis, but even the banal return of American astronauts from the ISS is difficult. In fact, we are talking about a proposal to deprive America of manned spaceflight. Seth Abramson Walter Isaacson The owner of SpaceX isn't letting things get boring either. As I wrote above, earlier this year, he stated, "We're going to fly straight to Mars. The moon is a distraction." The media, as usual, presented it as hype as possible: say, the most important person in the American space program does not want to fly to the Moon. Then there were “witnesses to the conspiracy”: SpaceX is not doing well with the lunar module, for which NASA paid the company $2.89 billion. Here he is trying to find an excuse not to follow the contracts! he stated In fact, Musk wrote these words in response to a question from another space enthusiast. The latter asked if Starship going to Mars should be refueled with lunar oxygen. The question, at first glance, is reasonable: 69% of the fuel mass of such a ship is oxygen. Answering, the head of SpaceX meant that refueling on the Moon in the conditions of reusable carriers does not make economic sense. It is easier to deliver oxygen from Earth than to build a mini-city on Selene for O2 extraction. question from another space enthusiast Let it be a hype, but still, “Artemis III” by 2025 has accumulated quite serious problems: the Orion heat shield returned after the orbit of the Moon was cracked. That is, another test flight of the ship is needed. But there is no money for it: the Artemis project has generated such an expensive rocket (SLS) that one of its launches with the ship costs $4.1 billion. $4.1 billion The head of SpaceX summarized all this: "The architecture of Artemis is extremely inefficient. This is a program to increase employment, not to achieve results. Something fundamentally new is needed." head of SpaceX summarized all this Let us return to the place of the invited project manager and ask ourselves a question: What would we suggest to ourselves? Already Solved Controls One often hears: Why does Artemis even need a lunar module and ship separately? We are already seeing the seventh Starship test flight. Yes, there are flaws, but it is obvious that by 2027, it will be flying regularly. There are also unlikely to be problems with the life support system, as SpaceX has already made one for Dragon ships. Why not take astronauts to the Moon, land them directly on Starship HLS, and then return to Earth on it? This approach to project management can be tentatively called “new broom”. Often, a new manager wants to radically change everything, to sweep away unnecessary crutches left by his predecessors. And then “make everything normal and fast”. In practice, this approach is not applicable. First, for a launch from Earth on a ship without a very large statistics of accident-free flights, it is desirable to have an emergency rescue system. Technically, this is a set of small engines to separate the ship from the rocket if it malfunctions. And, of course, a parachute system for atmospheric braking. Starship doesn't and won't have all of that. Otherwise, the ship would have to be radically redesigned, which takes a lot of time. And the developer doesn't want to, noting that airliners don't have parachutes. And Elon Musk is going to make an airliner for space (a mass and cheap carrier), not a simple experimental airplane with a parachute. Then, there is a temptation to take another ready-made piece of space technology - the manned SpaceX Dragon. Launch astronauts into orbit on it, dock it with Starship, and then launch it to the Moon for a human landing mission. This would solve the problem with the escape system: the Dragon has one. But for all the appeal of this option, it is quite difficult to implement. Existing versions of Starship simply don't have enough fuel to fly back to Earth from the Moon after the astronauts lift off. Unlike a ship like Orion, Starship is very massive. Of course, it is possible to refuel Starship in near-lunar orbit and then return it to our planet. But that would require many additional Starship tanker flights. To send one fuel tanker to the Moon, it would have to be refueled in Earth's orbit. What if, during landing or takeoff, a Starship tanker damages the launch equipment at one site, say, Starbase in Texas? That would clearly block the next flights from there. The wait for refueling could get longer. And what if another tanker damages the launch spot at the second launch pad for the Starship being built in Florida as well? Will astronauts wait months in orbit, enjoying the magnificent views? Casey Handmer's Option Physicist Casey Handmer, who used to work with NASA, offered a different solution four years ago. Yes, for a full-fledged Starship with a 100-ton payload, a return from the Moon is realistic only after complex refueling in low lunar orbit. But what if the ship's payload is reduced on the first flight? offered a different solution Handmer calculated that with 25 tons of payload, 12 refuelings in low-Earth orbit would allow the ship to fly to the Moon and return. Refueling in higher orbits is theoretically possible. It would give Starship the ability to deliver 200+ tons of payload to the Moon and then return the crew and tons of lunar soil. But there just isn't enough room inside the ship for 200 tons of cargo. Unless you want to mount an Olympic swimming pool inside and launch whales into it, the physicist notes. If anyone doubts the scientist's calculations, it is not difficult to check them yourself. Delta-V, the energy budget for reaching certain points of the Solar System (simply put, by how much the ship's speed should be changed), is well known. First, note that all calculations on this indicator for Starship are given after the launch into low-Earth orbit. In any case, refueling will take place there - the tanks will be full, and the delta-V countdown should be started again. To get from low Earth orbit (200 km) to geo-transition orbit (from about 200 km at perigee to 36,000 km at apogee), you need a delta of 2.44 km/s. To go to the Moon from this orbit would require 0.68 km/s of additional velocity. To reach a low lunar orbit (100 km above the Moon) - another 0.82 km/s. Landing on the Moon is already more difficult: there is no atmosphere here, against which we can extinguish the speed. So we will spend 1.72 km/s delta-V for braking on landing and another 1.72 km/s for takeoff a few days later. Another 0.82 km/s is needed to send it to Earth. That is, the total delta-V (after reaching low-Earth orbit, where refueling will take place) is about 8.2 km/s in total. That is quite capable for Starship with those parameters of the engines (380 seconds of impulse in vacuum), which are planned by SpaceX. Will 25 tons be enough for everyone? 25 tons for three astronauts may look like a severe limitation. After all, not only do they and their in-ship and out-of-ship spacesuits have to be stuffed into that load somehow, but also the equipment for traveling on the Moon. Without lunomobiles, traveling in the lunar shadow at -190 and below is no easy walk. It's worth remembering here that the mass of Apollo-era lunar modules is an unhelpful load. Namely, the total mass was only a dozen and a half tons. Sure, on the way to the Moon, the astronauts used the air, water, and food of the command module, which didn't fit into those 15 tons. But their total mass didn't even reach a ton. So maybe the astronauts in 2027 will have to shrink - but they certainly won't have to sleep sitting up like their 1960s counterparts. I don't think we should sympathize with astronauts about the tightness just yet. Musk, who employs his own style of project management, has heavily revised the final look of his brainchild over the past three years. Starship V3 should already have a payload of 200 tons, not 100 as Handmer had calculated. At the same time, the fuel mass is 2,300 tons. That is, full refueling in orbit will require about the same 12 tanker flights as before. Counting with the same dry mass proportions, we get a payload of more than 25 tons. we get a payload What in Handmer's calculations looks problematic? He thinks it's rational to land Starship HLS directly on Earth with people inside. This is questionable for two reasons. First, then it needs heat shielding like a regular Starship, and landing legs like its extraterrestrial version - there is no Mechazilla on the Moon yet. And that would reduce its payload on the Moon. Secondly, landing with astronauts can be done only after several tests without humans. The spacecraft is new. There is no experience of its operation yet. And if Starship cargo flights will soon be in abundance, we will not be able to say that about landings of manned versions. Besides, if we first send one Starship to the Moon with cargo but without the task of taking off again, it will have a “surplus” delta-V of at least 2.54 km/s. That means it will be able to deliver literally hundreds of tons of equipment to the Earth's satellite. It is possible to place not only lunomobiles but also mini-drilling machines, which are very useful for studying the south pole of the Moon. Let's summarize: the most realistic scenario for rebuilding the lunar program under the new administration is Handmer's version. Only slightly modified, in which people will get on board the Starship in Earth orbit with pre-launched Dragon. And it would return them to Earth after returning from the Moon. Such a launch will throw out of the flight program two launches of Orion on SLS: the first to test the updated heat shield and the second with people on board. In total, it saves $9 billion. What the real players are planning There have been leaks in the US press that seem to say that Handmer's option has already been adopted. In December 2024, renowned journalist Eric Berger presented data from his sources in the industry: the new NASA leadership is planning to abandon Orion and SLS. Technically, this is only possible if the new head of NASA, Jared Isaacman, commander of the first private space crew in history, plans to rely solely on SpaceX technology to fly to the moon. After all, no one else has any other rockets and ships of this class. Of course, Bill Nelson, head of NASA, tried to deny that leak. He gave an interview to the same Eric Berger and stated that Trump would not risk scrapping Orion and SLS. So as not to lose the race to the Chinese and definitely have time to see astronauts on the moon before the end of his term. Bill Nelson gave an interview But I will remind you that NASA astronauts did not just affectionately nickname Bill “Ballast” Nelson. The nickname has a basis: The politician is not very well versed in space issues. For example, he stated that one side of the moon is dark all the time. Of course, that's better than if he thought it was flat. But his overall level of understanding of the Artemis issues is still hard to call excessively high. nickname Bill “Ballast” Nelson he stated The position of Nelson and other politicians whose careers have been associated with SLS and Orion is understandable. They don't like the prospect of curtailing “job growth programs.” They've spent a lot of effort to maintain them and have associated their name with their success. Except neither Trump nor Musk are involved - and a Handmer-esque shakeup of the lunar program could very well become a reality. That's not to say there's an easy ride ahead for astronauts on their way to the moon. The issue of spacesuits is not yet closed. If we do not radically accelerate, then by 2027, there may be no working “iron”. The Starship trials are another non-obvious story. On the one hand, they are progressing rapidly. On the other hand, it is a reusable system. You need more flights to be sure of its reliability than with a disposable one. Personally, I expect more than a dozen Starship launches this year and a few dozen in 2026. And next year, there will mostly be not so many test flights as satellite-oriented. Perhaps this is the most reliable link of the American lunar program of the XXI century. Therefore, the decision to bet on it and get off the stagecoach such expensive passengers, such as Orion and SLS, looks really logical.

Trump Wants Astronauts On the Moon But Musk Has Other Plans

The entire market sentiment in December was dominated by the wealth effect, with ORDI’s thousandfold increase in active Inscription. A hundredfold increase was driven by $MOBILE in the DePIN. The Starknet airdrop plan has been continuously mentioned since the beginning of the month. The first two experienced explosions after a long period of silence; Starknet, on the other hand, was already hailed as an L2 star project alongside Arbitrum, Optimism, and zkSync a year ago: Raised $260 million with a valuation of $8 billion; TVL surpassed the $100 million mark, attracting an increasing number of users. Combined with the Optimism airdrop in June last year and the Arbitrum airdrop in March, which brought case after case of financial freedom, people’s expectations for the Starknet airdrop are at an all-time high. On December 1st, the Starknet Foundation announced that they had taken a snapshot for the airdrop and would distribute STRK tokens to past active users and contributors in the first quarter of 2024, unlocking previously distributed tokens. Early entrants are marking their calendars, eagerly awaiting the drawing; some are concerned that their interaction depth may not be enough to receive a substantial airdrop, and there are those who haven’t participated at all. Can outsiders only silently observe the celebration of others? Although Starknet has finalized the snapshot, most of the protocols on Starknet have not yet disclosed their airdrop plans. Based on past experience, most projects on these star ecosystems are likely to issue their own tokens. For example, Astraly, the token distribution platform on Starknet, has explicitly mentioned future airdrop plans in community responses: Official Support + Star Effect Starknet strongly supports projects in its own ecosystem: “Devonomics Pilot Program”: This program will distribute 10% of all transaction operator fees to developers building on Starknet since its launch in November of last year, totaling 1600 ETH. Of this, 8% will be allocated to dApp developers, providing 1280 ETH, and 2% will be allocated to core developers, providing 320 ETH. In the future, allocations will switch to using the Starknet token STRK. With official support and the star effect of Starknet itself, there are countless projects in the ecosystem: How do you find Alpha projects? Projects in the official recommended list have a basic guarantee of quality. However, referring to Starknet’s recommended page, even The Best Starknet Dapps recommended by the official has nearly 100 projects. The time and effort required for interaction with 100 projects are relatively high. How to quickly experience these projects? Solution: task platforms. For projects in need of growth, active project parties will choose to release activities through task platforms to attract users. Compared to well-established Web2 task platforms like Gleam, more and more Web3 platforms are widely adopted because they support the release of on-chain tasks. How extensive is the coverage of these Web3 task platforms? Referring to the recommended cross-chain bridge projects on the Starknet official page, it can be seen that the project coverage on task platforms is relatively high. Although not complete, one website can understand the most recommended projects and directly participate in project activities, saving a lot of time and effort. The wealth effect dominated the entire market sentiment in December. In Galxe, TaskOn, and similar platforms, the main purpose of launching activities is to attract users, so the threshold for tasks is relatively low and easy to complete. Common task configurations include following social media, joining communities, and completing PoW tasks or entry-level on-chain tasks to help users quickly familiarize themselves with the product. For understanding a project, this is the best start. The rewards for these activities are also diverse, including NFTs, whitelist spots, stablecoins, Discord roles, etc. Platforms like Galxe OAT and TaskOn’s CAP offer official NFT credentials, serving as on-chain proof of a user’s contribution to a project’s activity. While you may not become an early participant in the Starknet ecosystem, you can still be an early user of these applications. Starting with task platforms, you can quickly find your Alpha project. Also published . here

Starknet's Astronomical Rise and Potential Airdrop Opportunities with the Starknet Eco

Scientific American, Vol. XXXIX. No. 6. [New Series.], August 10, 1878, by Various, is part of the HackerNoon Books Series. You can jump to any chapter in this book . ASTRONOMICAL NOTES. here ASTRONOMICAL NOTES. BY BERLIN H. WRIGHT. Penn Yan, N. Y., Saturday, August 10, 1878. The following calculations are adapted to the latitude of New York city, and are expressed in true or clock time, being for the date given in the caption when not otherwise stated. PLANETS. H.M. H.M. Mercury sets 8 03 eve. Saturn rises 8 59 eve. Venus rises 2 42 mo. Saturn in meridian 2 58 mo. Jupiter in meridian 10 52 eve. Neptune rises 10 27 eve. FIRST MAGNITUDE STARS H.M. H.M. Alpheratz rises 6 54 eve. Regulus sets 7 29 eve. Algol (var.) rises 8 34 eve. Spica sets 9 24 eve. 7 stars (Pleiades) rise 10 53 eve. Arcturus sets 0 08 mo. Aldebaran rises 0 17 mo. Antares sets 11 24 eve. Capella rises 9 40 eve. Vega in meridian 9 15 eve. Rigel Rises 2 23 mo. Altair in meridian 10 27 eve. Betelgeuse rises 2 08 mo. Deneb in meridian 11 19 eve. Sirius rises 4 24 mo. Fomalhaut rises 9 34 eve. Procyon rises 3 59 mo. REMARKS Mercury is brightest this date, and furthest from the sun August 13. Venus will be at her descending node August 17. Jupiter will be near the moon August 17, 4h. 20m. morning, being the moon's apparent diameter north; this will be an occultation south of the equator. Saturn will be near the moon August 16, being about 7° south. There will be a partial eclipse of the moon August 16, in the evening. The moon will rise more or less eclipsed east of Kansas, west of which no eclipse will be visible. Middle. End. H.M. H.M. Boston 7 24 eve. 8 50 eve. New York 7 12 eve. 8 38 eve. Washington 7 00 eve. 8 26 eve. Charleston 6 48 eve. 8 14 eve. Chicago ———— 7 44 eve. St. Louis ———— 7 33 eve. New Orleans ———— 7 34 eve. The following shows the appearance of the moon when the eclipse is greatest -7·1 digits, or 0·596 of the moon's diameter. The size of the eclipse will be the same for all places. The time of middle and end for any other places may be obtained by applying the difference of longitude from Washington, converted into time, to the Washington time of middle and end, adding if east of Washington, and subtracting if west. An Interesting Astronomical Observation. To the Editor of the Scientific American: While viewing the planet Jupiter, at about 5 minutes past 10 o'clock P.M., a very strange sight presented itself to the observers, who were looking for a transit of one of the satellites. A very dark spot much larger than a satellite was seen on the eastern edge of the disk, as shown in the above diagram. It moved rapidly westward along the upper margin of the northern belt and passed off at 1 o'clock 24 minutes A.M. (12th). From its first internal contact till its last external contact was just 3h. 19m., Pittsburg time. It appeared to be a solid opaque body, truly spherical, very sharply defined, and most intensely black. The transit of the satellite occurred at 15 minutes after 11 o'clock, and had no unusual appearance. Now what was that dark body? We are constant observers of the heavenly bodies, though not deeply versed in the science of astronomy, and are anxious to know if any one can give us some light on the subject. The telescopes used were a 2½ inch and 5 inch achromatic, magnifying 154 and 216 diameters, but the 154 was chiefly used. was chiefly used. Joseph Wampler. James R. Gemmill. McKeesport, Pa., July 11, 1878. Some of Professor Marsh's Recent Discoveries. Mr. S. W. Williston, the assistant of Professor Marsh, has been giving to the Omaha some interesting facts with regard to the great reptilian fossils recently discovered in Wyoming and Colorado. The bones found represent reptiles of many sizes, from that of a cat up to one sixty feet high. The latter, found at Como, Wyoming, belonged to the crocodile order; but the remains give evidence that the animal stood up on its hind legs, like a kangaroo. Another found in Colorado is estimated by Professor Marsh to have been 100 feet long. A great many remains of the same general class, but belonging to different species, have been collected and sent East. Among them from three to four hundred specimens of the dinosaur, and about a thousand pterodactyls, have been shipped from Colorado, Wyoming, and Kansas. The wings of one of the latter were from thirty to forty feet from tip to tip. Seventeen different species of these flying dragons have been found in the chalk of western Kansas. There have also been found six species of toothed birds. Comparatively little has been done toward classifying the late finds, the task is such an enormous one. Great importance is attached to them, however, since nothing of the kind had been found in America until a little over a year ago and great stress had been laid by certain geologists on their absence. Another remarkable feature of the discovery was that the fossils which had been reported as not existing in this country had hardly been brought to light in one locality before thousands of tons of them were simultaneously discovered in half a dozen different places. Bee Trying to Save a Hundred and Fifty Million Dollars a Year. Professor Riley, recently appointed Government Entomologist and attached to the Agricultural Department, reports that specimens of insects injurious to agriculture are constantly being sent to the department from all parts of the country, with requests for information. In every instance, if a proper examination could be made, an effectual remedy could be found, and not less than $150,000,000 saved to the country annually. Recently a worm entirely new to science was sent to the department by an Iowa farmer, whose orchard of several thousand apple trees had been rendered unproductive for several years by the new depredator. For the interests of Western fruit growers this insect should immediately be investigated. Professor Riley asserts that the $5,000 recently voted by Congress for the investigation of the cotton worm, which has sometimes damaged the cotton crop of the South as much as $20,000,000 in a single fortnight, might have been used to better advantage by the department; the salary of the entomologist will use up all the money, leaving next to nothing for experiments for the eradication of the pest. Industrial Education. All are agreed that some education is necessary; but what? The great proportion of those having the direction of our educational system and facilities in charge still cling to a system which was established long before the first mechanical operation came into existence. Before the present system of man's relation to man, socially, industrially, politically, or commercially, was heard of, and notwithstanding the revolutions and advancement in all other things, there is a determined resistance to any attempt at revolution in what shall be considered education. There is an effort to establish compulsory education; but what is the child to be taught? As if in league with the false theories of the rights of labor, these efforts take the apprentices from the shops, force them away from where they would learn something, and confine them inside a school house to learn—what? Certainly nothing of the materials, or tools, or pursuits by which they are to obtain their livelihood. The child knows nothing of when or by whom the compass was discovered, the printing press, the use of powder, electricity, of steam, or of any one of the thousand mechanical operations now controlling every department of life. Does any school boy know how many kingdoms there are in the natural world, or whether an animal, a vegetable and a mineral all belong to the same or to different ones? Will he know that from instinct the young of animals seeks its food and expands its lungs, as by the same instinct the root of a seed sucks up its nourishment from the soil and sends its leaves up to breathe the air? Will he know anything of the nature or requirements of the soils or the plants that grow in them? Will this compulsory education teach the boy anything of the iron furnace, the foundry or rolling mill, or the uses or handling of any of their products? Will it teach him anything of woods and their value, or for what and how they are useful to man? Will this knowledge, for which the powers of the State are to be required to force him to know it—will it teach him anything of the nature or uses of metals, of metal working, or the business depending upon them? Will it teach him anything of gold or silver, copper or brass? Anything of pottery, of bone, ivory, celluloid, etc.? Will he learn anything of hides, leather, or the production of these necessary articles? Will he know whether the word textile applies to anything but a spider's web or the wing of a butterfly? Whether the United States make, import, or grow cotton, wool, silk, flax, and hemp? Will he know anything of commerce, railroads, telegraphs, printing, and the great number of clerk labors in the larger towns? Will he have learned a single thing which will assist him in his work of life? Will not every boy thus taken out of the shop and placed at the compulsory schooling find after he has mastered all it has to give him that he yet knows nothing; that he must then commence where he was and serve his apprenticeship; that instead of compulsory education his past years have been wasted in obtaining but a compulsory ignorance? About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Various (2013). Scientific American, Vol. XXXIX. No. 6. [New Series.], August 10, 1878. Urbana, Illinois: Project Gutenberg. Retrieved https://www.gutenberg.org/cache/epub/19406/pg19406-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at www.gutenberg.org https://www.gutenberg.org/policy/license.html

ASTRONOMICAL NOTES

Off on a Comet! a Journey through Planetary Space by Jules Verne, is part of the HackerNoon Books Series. You can jump to any chapter in this book . THE ASTRONOMER here CHAPTER I. THE ASTRONOMER By the return of the expedition, conveying its contribution from Formentera, the known population of Gallia was raised to a total of thirty-six. On learning the details of his friends’ discoveries, Count Timascheff did not hesitate in believing that the exhausted individual who was lying before him was the author alike of the two unsigned documents picked up at sea, and of the third statement so recently brought to hand by the carrier-pigeon. Manifestly, he had arrived at some knowledge of Gallia’s movements: he had estimated her distance from the sun; he had calculated the diminution of her tangential speed; but there was nothing to show that he had arrived at the conclusions which were of the most paramount interest to them all. Had he ascertained the true character of her orbit? had he established any data from which it would be possible to reckon what time must elapse before she would again approach the earth? The only intelligible words which the astronomer had uttered had been, “My comet!” To what could the exclamation refer? Was it to be conjectured that a fragment of the earth had been chipped off by the collision of a comet? and if so, was it implied that the name of the comet itself was Gallia, and were they mistaken in supposing that such was the name given by the to the little world that had been so suddenly launched into space? Again and again they discussed these questions; but no satisfactory answer could be found. The only man who was able to throw any light upon the subject was lying amongst them in an unconscious and half-dying condition. savant Apart from motives of humanity, motives of self-interest made it a matter of the deepest concern to restore animation to that senseless form. Ben Zoof, after making the encouraging remark that have as many lives as a cat, proceeded, with Negrete’s assistance, to give the body such a vigorous rubbing as would have threatened serious injury to any ordinary mortal, whilst they administered cordials and restoratives from the medical stores powerful enough, one might think, to rouse the very dead. savants Dobryna’s Meanwhile the captain was racking his brain in his exertions to recall what were the circumstances of his previous acquaintance with the Frenchman upon whose features he was gazing; he only grew more and more convinced that he had once been familiar with them. Perhaps it was not altogether surprising that he had almost forgotten him; he had never seen him since the days of his youth, that time of life which, with a certain show of justice, has been termed the age of ingratitude; for, in point of fact, the astronomer was none other than Professor Palmyrin Rosette, Servadac’s old science-master at the Lycee Charlemagne. After completing his year of elementary studies, Hector Servadac had entered the school at Saint Cyr, and from that time he and his former tutor had never met, so that naturally they would well-nigh pass from each other’s recollection. One thing, however, on the other hand, might conduce to a mutual and permanent impression on their memories; during the year at the Lycee, young Servadac, never of a very studious turn of mind, had contrived, as the ringleader of a set of like caliber as himself, to lead the poor professor a life of perpetual torment. On the discovery of each delinquency he would fume and rage in a manner that was a source of unbounded delight to his audience. Two years after Servadac left the Lycee, Professor Rosette had thrown up all educational employment in order that he might devote himself entirely to the study of astronomy. He endeavored to obtain a post at the Observatory, but his ungenial character was so well known in scientific circles that he failed in his application; however, having some small private means, he determined on his own account to carry on his researches without any official salary. He had really considerable genius for the science that he had adopted; besides discovering three of the latest of the telescopic planets, he had worked out the elements of the three hundred and twenty-fifth comet in the catalogue; but his chief delight was to criticize the publications of other astronomers, and he was never better pleased than when he detected a flaw in their reckonings. When Ben Zoof and Negrete had extricated their patient from the envelope of furs in which he had been wrapped by Servadac and the lieutenant, they found themselves face to face with a shrivelled little man, about five feet two inches high, with a round bald head, smooth and shiny as an ostrich’s egg, no beard unless the unshorn growth of a week could be so described, and a long hooked nose that supported a huge pair of spectacles such as with many near-sighted people seems to have become a part of their individuality. His nervous system was remarkably developed, and his body might not inaptly be compared to one of the Rhumkorff’s bobbins of which the thread, several hundred yards in length, is permeated throughout by electric fluid. But whatever he was, his life, if possible, must be preserved. When he had been partially divested of his clothing, his heart was found to be still beating, though very feebly. Asserting that while there was life there was hope, Ben Zoof recommenced his friction with more vigor than ever. When the rubbing had been continued without a moment’s intermission for the best part of half an hour, the astronomer heaved a faint sigh, which ere long was followed by another and another. He half opened his eyes, closed them again, then opened them completely, but without exhibiting any consciousness whatever of his situation. A few words seemed to escape his lips, but they were quite unintelligible. Presently he raised his right hand to his forehead as though instinctively feeling for something that was missing; then, all of a sudden, his features became contracted, his face flushed with apparent irritation, and he exclaimed fretfully, “My spectacles!—where are my spectacles?” In order to facilitate his operations, Ben Zoof had removed the spectacles in spite of the tenacity with which they seemed to adhere to the temples of his patient; but he now rapidly brought them back and readjusted them as best he could to what seemed to be their natural position on the aquiline nose. The professor heaved a long sigh of relief, and once more closed his eyes. Before long the astronomer roused himself a little more, and glanced inquiringly about him, but soon relapsed into his comatose condition. When next he opened his eyes, Captain Servadac happened to be bending down closely over him, examining his features with curious scrutiny. The old man darted an angry look at him through the spectacles, and said sharply, “Servadac, five hundred lines to-morrow!” It was an echo of days of old. The words were few, but they were enough to recall the identity which Servadac was trying to make out. “Is it possible?” he exclaimed. “Here is my old tutor, Mr. Rosette, in very flesh and blood.” “Can’t say much for the flesh,” muttered Ben Zoof. The old man had again fallen back into a torpid slumber. Ben Zoof continued, “His sleep is getting more composed. Let him alone; he will come round yet. Haven’t I heard of men more dried up than he is, being brought all the way from Egypt in cases covered with pictures?” “You idiot!—those were mummies; they had been dead for ages.” Ben Zoof did not answer a word. He went on preparing a warm bed, into which he managed to remove his patient, who soon fell into a calm and natural sleep. Too impatient to await the awakening of the astronomer and to hear what representations he had to make, Servadac, the count, and the lieutenant, constituting themselves what might be designated “the Academy of Sciences” of the colony, spent the whole of the remainder of the day in starting and discussing the wildest conjectures about their situation. The hypothesis, to which they had now accustomed themselves for so long, that a new asteroid had been formed by a fracture of the earth’s surface, seemed to fall to the ground when they found that Professor Palmyrin Rosette had associated the name of Gallia, not with their present home, but with what he called “my comet”; and that theory being abandoned, they were driven to make the most improbable speculations to replace it. Alluding to Rosette, Servadac took care to inform his companions that, although the professor was always eccentric, and at times very irascible, yet he was really exceedingly good-hearted; his bark was worse than his bite; and if suffered to take their course without observation, his outbreaks of ill-temper seldom lasted long. “We will certainly do our best to get on with him,” said the count. “He is no doubt the author of the papers, and we must hope that he will be able to give us some valuable information.” “Beyond a question the documents have originated with him,” assented the lieutenant. “Gallia was the word written at the top of every one of them, and Gallia was the first word uttered by him in our hearing.” The astronomer slept on. Meanwhile, the three together had no hesitation in examining his papers, and scrutinizing the figures on his extemporized blackboard. The handwriting corresponded with that of the papers already received; the blackboard was covered with algebraical symbols traced in chalk, which they were careful not to obliterate; and the papers, which consisted for the most part of detached scraps, presented a perfect wilderness of geometrical figures, conic sections of every variety being repeated in countless profusion. Lieutenant Procope pointed out that these curves evidently had reference to the orbits of comets, which are variously parabolic, hyperbolic, or elliptic. If either of the first two, the comet, after once appearing within the range of terrestrial vision, would vanish forever in the outlying regions of space; if the last, it would be sure, sooner or later, after some periodic interval, to return. From the appearance of his papers, then, it seemed probable that the astronomer, during his sojourn at Formentera, had been devoting himself to the study of cometary orbits; and as calculations of this kind are ordinarily based upon the assumption that the orbit is a parabola, it was not unlikely that he had been endeavoring to trace the path of some particular comet. prima facie “I wonder whether these calculations were made before or after the 1st of January; it makes all the difference,” said Lieutenant Procope. “We must bide our time and hear,” replied the count. Servadac paced restlessly up and down. “I would give a month of my life,” he cried, impetuously, “for every hour that the old fellow goes sleeping on.” “You might be making a bad bargain,” said Procope, smiling. “Perhaps after all the comet has had nothing to do with the convulsion that we have experienced.” “Nonsense!” exclaimed the captain; “I know better than that, and so do you. Is it not as clear as daylight that the earth and this comet have been in collision, and the result has been that our little world has been split off and sent flying far into space?” Count Timascheff and the lieutenant looked at each other in silence. “I do not deny your theory,” said Procope after a while. “If it be correct, I suppose we must conclude that the enormous disc we observed on the night of the catastrophe was the comet itself; and the velocity with which it was traveling must have been so great that it was hardly arrested at all by the attraction of the earth.” “Plausible enough,” answered Count Timascheff; “and it is to this comet that our scientific friend here has given the name of Gallia.” It still remained a puzzle to them all why the astronomer should apparently be interested in the comet so much more than in the new little world in which their strange lot was cast. “Can you explain this?” asked the count. “There is no accounting for the freaks of philosophers, you know,” said Servadac; “and have I not told you that this philosopher in particular is one of the most eccentric beings in creation?” “Besides,” added the lieutenant, “it is exceedingly likely that his observations had been going on for some considerable period before the convulsion happened.” Thus, the general conclusion arrived at by the Gallian Academy of Science was this: That on the night of the 31st of December, a comet, crossing the ecliptic, had come into collision with the earth, and that the violence of the shock had separated a huge fragment from the globe, which fragment from that date had been traversing the remote inter-planetary regions. Palmyrin Rosette would doubtless confirm their solution of the phenomenon. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Jules Verne (1998). Off on a Comet! a Journey through Planetary Space. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/1353/pg1353-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at . www.gutenberg.org https://www.gutenberg.org/policy/license.html

THE ASTRONOMER

The Astronomy

Great Astronomers by Robert S. Ball, is part of the HackerNoon Books Series. You can jump to any chapter in this book here. COPERNICUS COPERNICUS THORN, FROM AN OLD PRINT. The quaint town of Thorn, on the Vistula, was more than two centuries old when Copernicus was born there on the 19th of February, 1473. The situation of this town on the frontier between Prussia and Poland, with the commodious waterway offered by the river, made it a place of considerable trade. A view of the town, as it was at the time of the birth of Copernicus, is here given. The walls, with their watch-towers, will be noted, and the strategic importance which the situation of Thorn gave to it in the fifteenth century still belongs thereto, so much so that the German Government recently constituted the town a fortress of the first class. Copernicus, the astronomer, whose discoveries make him the great predecessor of Kepler and Newton, did not come from a noble family, as certain other early astronomers have done, for his father was a tradesman. Chroniclers are, however, careful to tell us that one of his uncles was a bishop. We are not acquainted with any of those details of his childhood or youth which are often of such interest in other cases where men have risen to exalted fame. It would appear that the young Nicolaus, for such was his Christian name, received his education at home until such time as he was deemed sufficiently advanced to be sent to the University at Cracow. The education that he there obtained must have been in those days of a very primitive description, but Copernicus seems to have availed himself of it to the utmost. He devoted himself more particularly to the study of medicine, with the view of adopting its practice as the profession of his life. The tendencies of the future astronomer were, however, revealed in the fact that he worked hard at mathematics, and, like one of his illustrious successors, Galileo, the practice of the art of painting had for him a very great interest, and in it he obtained some measure of success. By the time he was twenty-seven years old, it would seem that Copernicus had given up the notion of becoming a medical practitioner, and had resolved to devote himself to science. He was engaged in teaching mathematics, and appears to have acquired some reputation. His growing fame attracted the notice of his uncle the bishop, at whose suggestion Copernicus took holy orders, and he was presently appointed to a canonry in the cathedral of Frauenburg, near the mouth of the Vistula. To Frauenburg, accordingly, this man of varied gifts retired. Possessing somewhat of the ascetic spirit, he resolved to devote his life to work of the most serious description. He eschewed all ordinary society, restricting his intimacies to very grave and learned companions, and refusing to engage in conversation of any useless kind. It would seem as if his gifts for painting were condemned as frivolous; at all events, we do not learn that he continued to practise them. In addition to the discharge of his theological duties, his life was occupied partly in ministering medically to the wants of the poor, and partly with his researches in astronomy and mathematics. His equipment in the matter of instruments for the study of the heavens seems to have been of a very meagre description. He arranged apertures in the walls of his house at Allenstein, so that he could observe in some fashion the passage of the stars across the meridian. That he possessed some talent for practical mechanics is proved by his construction of a contrivance for raising water from a stream, for the use of the inhabitants of Frauenburg. Relics of this machine are still to be seen. COPERNICUS. The intellectual slumber of the Middle Ages was destined to be awakened by the revolutionary doctrines of Copernicus. It may be noted, as an interesting circumstance, that the time at which he discovered the scheme of the solar system has coincided with a remarkable epoch in the world's history. The great astronomer had just reached manhood at the time when Columbus discovered the new world. Before the publication of the researches of Copernicus, the orthodox scientific creed averred that the earth was stationary, and that the apparent movements of the heavenly bodies were indeed real movements. Ptolemy had laid down this doctrine 1,400 years before. In his theory this huge error was associated with so much important truth, and the whole presented such a coherent scheme for the explanation of the heavenly movements, that the Ptolemaic theory was not seriously questioned until the great work of Copernicus appeared. No doubt others, before Copernicus, had from time to time in some vague fashion surmised, with more or less plausibility, that the sun, and not the earth, was the centre about which the system really revolved. It is, however, one thing to state a scientific fact; it is quite another thing to be in possession of the train of reasoning, founded on observation or experiment, by which that fact may be established. Pythagoras, it appears, had indeed told his disciples that it was the sun, and not the earth, which was the centre of movement, but it does not seem at all certain that Pythagoras had any grounds which science could recognise for the belief which is attributed to him. So far as information is available to us, it would seem that Pythagoras associated his scheme of things celestial with a number of preposterous notions in natural philosophy. He may certainly have made a correct statement as to which was the most important body in the solar system, but he certainly did not provide any rational demonstration of the fact. Copernicus, by a strict train of reasoning, convinced those who would listen to him that the sun was the centre of the system. It is useful for us to consider the arguments which he urged, and by which he effected that intellectual revolution which is always connected with his name. The first of the great discoveries which Copernicus made relates to the rotation of the earth on its axis. That general diurnal movement, by which the stars and all other celestial bodies appear to be carried completely round the heavens once every twenty-four hours, had been accounted for by Ptolemy on the supposition that the apparent movements were the real movements. As we have already seen, Ptolemy himself felt the extraordinary difficulty involved in the supposition that so stupendous a fabric as the celestial sphere should spin in the way supposed. Such movements required that many of the stars should travel with almost inconceivable velocity. Copernicus also saw that the daily rising and setting of the heavenly bodies could be accounted for either by the supposition that the celestial sphere moved round and that the earth remained at rest, or by the supposition that the celestial sphere was at rest while the earth turned round in the opposite direction. He weighed the arguments on both sides as Ptolemy had done, and, as the result of his deliberations, Copernicus came to an opposite conclusion from Ptolemy. To Copernicus it appeared that the difficulties attending the supposition that the celestial sphere revolved, were vastly greater than those which appeared so weighty to Ptolemy as to force him to deny the earth's rotation. Copernicus shows clearly how the observed phenomena could be accounted for just as completely by a rotation of the earth as by a rotation of the heavens. He alludes to the fact that, to those on board a vessel which is moving through smooth water, the vessel itself appears to be at rest, while the objects on shore seem to be moving past. If, therefore, the earth were rotating uniformly, we dwellers upon the earth, oblivious of our own movement, would wrongly attribute to the stars the displacement which was actually the consequence of our own motion. Copernicus saw the futility of the arguments by which Ptolemy had endeavoured to demonstrate that a revolution of the earth was impossible. It was plain to him that there was nothing whatever to warrant refusal to believe in the rotation of the earth. In his clear-sightedness on this matter we have specially to admire the sagacity of Copernicus as a natural philosopher. It had been urged that, if the earth moved round, its motion would not be imparted to the air, and that therefore the earth would be uninhabitable by the terrific winds which would be the result of our being carried through the air. Copernicus convinced himself that this deduction was preposterous. He proved that the air must accompany the earth, just as his coat remains round him, notwithstanding the fact that he is walking down the street. In this way he was able to show that all a priori objections to the earth's movements were absurd, and therefore he was able to compare together the plausibilities of the two rival schemes for explaining the diurnal movement. FRAUENBURG, FROM AN OLD PRINT. Once the issue had been placed in this form, the result could not be long in doubt. Here is the question: Which is it more likely—that the earth, like a grain of sand at the centre of a mighty globe, should turn round once in twenty-four hours, or that the whole of that vast globe should complete a rotation in the opposite direction in the same time? Obviously, the former is far the more simple supposition. But the case is really much stronger than this. Ptolemy had supposed that all the stars were attached to the surface of a sphere. He had no ground whatever for this supposition, except that otherwise it would have been well-nigh impossible to have devised a scheme by which the rotation of the heavens around a fixed earth could have been arranged. Copernicus, however, with the just instinct of a philosopher, considered that the celestial sphere, however convenient from a geometrical point of view, as a means of representing apparent phenomena, could not actually have a material existence. In the first place, the existence of a material celestial sphere would require that all the myriad stars should be at exactly the same distances from the earth. Of course, no one will say that this or any other arbitrary disposition of the stars is actually impossible, but as there was no conceivable physical reason why the distances of all the stars from the earth should be identical, it seemed in the very highest degree improbable that the stars should be so placed. Doubtless, also, Copernicus felt a considerable difficulty as to the nature of the materials from which Ptolemy's wonderful sphere was to be constructed. Nor could a philosopher of his penetration have failed to observe that, unless that sphere were infinitely large, there must have been space outside it, a consideration which would open up other difficult questions. Whether infinite or not, it was obvious that the celestial sphere must have a diameter at least many thousands of times as great as that of the earth. From these considerations Copernicus deduced the important fact that the stars and the other celestial bodies must all be vast objects. He was thus enabled to put the question in such a form that it could hardly receive any answer but the correct one. Which is it more rational to suppose, that the earth should turn round on its axis once in twenty-four hours, or that thousands of mighty stars should circle round the earth in the same time, many of them having to describe circles many thousands of times greater in circumference than the circuit of the earth at the equator? The obvious answer pressed upon Copernicus with so much force that he was compelled to reject Ptolemy's theory of the stationary earth, and to attribute the diurnal rotation of the heavens to the revolution of the earth on its axis. Once this tremendous step had been taken, the great difficulties which beset the monstrous conception of the celestial sphere vanished, for the stars need no longer be regarded as situated at equal distances from the earth. Copernicus saw that they might lie at the most varied degrees of remoteness, some being hundreds or thousands of times farther away than others. The complicated structure of the celestial sphere as a material object disappeared altogether; it remained only as a geometrical conception, whereon we find it convenient to indicate the places of the stars. Once the Copernican doctrine had been fully set forth, it was impossible for anyone, who had both the inclination and the capacity to understand it, to withhold acceptance of its truth. The doctrine of a stationary earth had gone for ever. Copernicus having established a theory of the celestial movements which deliberately set aside the stability of the earth, it seemed natural that he should inquire whether the doctrine of a moving earth might not remove the difficulties presented in other celestial phenomena. It had been universally admitted that the earth lay unsupported in space. Copernicus had further shown that it possessed a movement of rotation. Its want of stability being thus recognised, it seemed reasonable to suppose that the earth might also have some other kinds of movements as well. In this, Copernicus essayed to solve a problem far more difficult than that which had hitherto occupied his attention. It was a comparatively easy task to show how the diurnal rising and setting could be accounted for by the rotation of the earth. It was a much more difficult undertaking to demonstrate that the planetary movements, which Ptolemy had represented with so much success, could be completely explained by the supposition that each of those planets revolved uniformly round the sun, and that the earth was also a planet, accomplishing a complete circuit of the sun once in the course of a year. EXPLANATION OF PLANETARY MOVEMENTS. It would be impossible in a sketch like the present to enter into any detail as to the geometrical propositions on which this beautiful investigation of Copernicus depended. We can only mention a few of the leading principles. It may be laid down in general that, if an observer is in movement, he will, if unconscious of the fact, attribute to the fixed objects around him a movement equal and opposite to that which he actually possesses. A passenger on a canal-boat sees the objects on the banks apparently moving backward with a speed equal to that by which he is himself advancing forwards. By an application of this principle, we can account for all the phenomena of the movements of the planets, which Ptolemy had so ingeniously represented by his circles. Let us take, for instance, the most characteristic feature in the irregularities of the outer planets. We have already remarked that Mars, though generally advancing from west to east among the stars, occasionally pauses, retraces his steps for awhile, again pauses, and then resumes his ordinary onward progress. Copernicus showed clearly how this effect was produced by the real motion of the earth, combined with the real motion of Mars. In the adjoining figure we represent a portion of the circular tracks in which the earth and Mars move in accordance with the Copernican doctrine. I show particularly the case where the earth comes directly between the planet and the sun, because it is on such occasions that the retrograde movement (for so this backward movement of Mars is termed) is at its highest. Mars is then advancing in the direction shown by the arrow-head, and the earth is also advancing in the same direction. We, on the earth, however, being unconscious of our own motion, attribute, by the principle I have already explained, an equal and opposite motion to Mars. The visible effect upon the planet is, that Mars has two movements, a real onward movement in one direction, and an apparent movement in the opposite direction. If it so happened that the earth was moving with the same speed as Mars, then the apparent movement would exactly neutralise the real movement, and Mars would seem to be at rest relatively to the surrounding stars. Under the actual circumstances represented, however, the earth is moving faster than Mars, and the consequence is, that the apparent movement of the planet backwards exceeds the real movement forwards, the net result being an apparent retrograde movement. With consummate skill, Copernicus showed how the applications of the same principles could account for the characteristic movements of the planets. His reasoning in due time bore down all opposition. The supreme importance of the earth in the system vanished. It had now merely to take rank as one of the planets. The same great astronomer now, for the first time, rendered something like a rational account of the changes of the seasons. Nor did certain of the more obscure astronomical phenomena escape his attention. He delayed publishing his wonderful discoveries to the world until he was quite an old man. He had a well-founded apprehension of the storm of opposition which they would arouse. However, he yielded at last to the entreaties of his friends, and his book was sent to the press. But ere it made its appearance to the world, Copernicus was seized by mortal illness. A copy of the book was brought to him on May 23, 1543. We are told that he was able to see it and to touch it, but no more, and he died a few hours afterwards. He was buried in that Cathedral of Frauenburg, with which his life had been so closely associated. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Robert S. Ball (2000). Great Astronomers. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/2298/pg2298-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

Copernicus:  The astronomer

The greatest figure in ancient astronomy

Great Astronomers by Robert S. Ball, is part of the HackerNoon Books Series. You can jump to any chapter in this book here . INTRODUCTION INTRODUCTION. Of all the natural sciences there is not one which offers such sublime objects to the attention of the inquirer as does the science of astronomy. From the earliest ages the study of the stars has exercised the same fascination as it possesses at the present day. Among the most primitive peoples, the movements of the sun, the moon, and the stars commanded attention from their supposed influence on human affairs. The practical utilities of astronomy were also obvious in primeval times. Maxims of extreme antiquity show how the avocations of the husbandman are to be guided by the movements of the heavenly bodies. The positions of the stars indicated the time to plough, and the time to sow. To the mariner who was seeking a way across the trackless ocean, the heavenly bodies offered the only reliable marks by which his path could be guided. There was, accordingly, a stimulus both from intellectual curiosity and from practical necessity to follow the movements of the stars. Thus began a search for the causes of the ever-varying phenomena which the heavens display. Many of the earliest discoveries are indeed prehistoric. The great diurnal movement of the heavens, and the annual revolution of the sun, seem to have been known in times far more ancient than those to which any human monuments can be referred. The acuteness of the early observers enabled them to single out the more important of the wanderers which we now call planets. They saw that the star-like objects, Jupiter, Saturn, and Mars, with the more conspicuous Venus, constituted a class of bodies wholly distinct from the fixed stars among which their movements lay, and to which they bear such a superficial resemblance. But the penetration of the early astronomers went even further, for they recognized that Mercury also belongs to the same group, though this particular object is seen so rarely. It would seem that eclipses and other phenomena were observed at Babylon from a very remote period, while the most ancient records of celestial observations that we possess are to be found in the Chinese annals. The study of astronomy, in the sense in which we understand the word, may be said to have commenced under the reign of the Ptolemies at Alexandria. The most famous name in the science of this period is that of Hipparchus who lived and worked at Rhodes about the year 160BC. It was his splendid investigations that first wrought the observed facts into a coherent branch of knowledge. He recognized the primary obligation which lies on the student of the heavens to compile as complete an inventory as possible of the objects which are there to be found. Hipparchus accordingly commenced by undertaking, on a small scale, a task exactly similar to that on which modern astronomers, with all available appliances of meridian circles, and photographic telescopes, are constantly engaged at the present day. He compiled a catalogue of the principal fixed stars, which is of special value to astronomers, as being the earliest work of its kind which has been handed down. He also studied the movements of the sun and the moon, and framed theories to account for the incessant changes which he saw in progress. He found a much more difficult problem in his attempt to interpret satisfactorily the complicated movements of the planets. With the view of constructing a theory which should give some coherent account of the subject, he made many observations of the places of these wandering stars. How great were the advances which Hipparchus accomplished may be appreciated if we reflect that, as a preliminary task to his more purely astronomical labours, he had to invent that branch of mathematical science by which alone the problems he proposed could be solved. It was for this purpose that he devised the indispensable method of calculation which we now know so well as trigonometry. Without the aid rendered by this beautiful art it would have been impossible for any really important advance in astronomical calculation to have been effected. But the discovery which shows, beyond all others, that Hipparchus possessed one of the master-minds of all time was the detection of that remarkable celestial movement known as the precession of the equinoxes. The inquiry which conducted to this discovery involved a most profound investigation, especially when it is remembered that in the days of Hipparchus the means of observation of the heavenly bodies were only of the rudest description, and the available observations of earlier dates were extremely scanty. We can but look with astonishment on the genius of the man who, in spite of such difficulties, was able to detect such a phenomenon as the precession, and to exhibit its actual magnitude. I shall endeavour to explain the nature of this singular celestial movement, for it may be said to offer the first instance in the history of science in which we find that combination of accurate observation with skilful interpretation, of which, in the subsequent development of astronomy, we have so many splendid examples. The word equinox implies the condition that the night is equal to the day. To a resident on the equator the night is no doubt equal to the day at all times in the year, but to one who lives on any other part of the earth, in either hemisphere, the night and the day are not generally equal. There is, however, one occasion in spring, and another in autumn, on which the day and the night are each twelve hours at all places on the earth. When the night and day are equal in spring, the point which the sun occupies on the heavens is termed the vernal equinox. There is similarly another point in which the sun is situated at the time of the autumnal equinox. In any investigation of the celestial movements the positions of these two equinoxes on the heavens are of primary importance, and Hipparchus, with the instinct of genius, perceived their significance, and commenced to study them. It will be understood that we can always define the position of a point on the sky with reference to the surrounding stars. No doubt we do not see the stars near the sun when the sun is shining, but they are there nevertheless. The ingenuity of Hipparchus enabled him to determine the positions of each of the two equinoxes relatively to the stars which lie in its immediate vicinity. After examination of the celestial places of these points at different periods, he was led to the conclusion that each equinox was moving relatively to the stars, though that movement was so slow that twenty five thousand years would necessarily elapse before a complete circuit of the heavens was accomplished. Hipparchus traced out this phenomenon, and established it on an impregnable basis, so that all astronomers have ever since recognised the precession of the equinoxes as one of the fundamental facts of astronomy. Not until nearly two thousand years after Hipparchus had made this splendid discovery was the explanation of its cause given by Newton. From the days of Hipparchus down to the present hour the science of astronomy has steadily grown. One great observer after another has appeared from time to time, to reveal some new phenomenon with regard to the celestial bodies or their movements, while from time to time one commanding intellect after another has arisen to explain the true import of the facts of observations. The history of astronomy thus becomes inseparable from the history of the great men to whose labours its development is due. In the ensuing chapters we have endeavoured to sketch the lives and the work of the great philosophers, by whose labours the science of astronomy has been created. We shall commence with Ptolemy, who, after the foundations of the science had been laid by Hipparchus, gave to astronomy the form in which it was taught throughout the Middle Ages. We shall next see the mighty revolution in our conceptions of the universe which are associated with the name of Copernicus. We then pass to those periods illumined by the genius of Galileo and Newton, and afterwards we shall trace the careers of other more recent discoverers, by whose industry and genius the boundaries of human knowledge have been so greatly extended. Our history will be brought down late enough to include some of the illustrious astronomers who laboured in the generation which has just passed away. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Robert S. Ball (2000). Great Astronomers. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/2298/pg2298-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

The practical utilities of astronomy

Great Astronomers by Robert S. Ball, is part of the HackerNoon Books Series. You can jump to any chapter in this book here . PREFACE PREFACE. It has been my object in these pages to present the life of each astronomer in such detail as to enable the reader to realise in some degree the man's character and surroundings; and I have endeavoured to indicate as clearly as circumstances would permit the main features of the discoveries by which he has become known. There are many types of astronomers—from the stargazer who merely watches the heavens, to the abstract mathematician who merely works at his desk; it has, consequently, been necessary in the case of some lives to adopt a very different treatment from that which seemed suitable for others. While the work was in progress, some of the sketches appeared in "Good Words." The chapter on Brinkley has been chiefly derived from an article on the "History of Dunsink Observatory," which was published on the occasion of the tercentenary celebration of the University of Dublin in 1892, and the life of Sir William Rowan Hamilton is taken, with a few alterations and omissions, from an article contributed to the "Quarterly Review" on Graves' life of the great mathematician. The remaining chapters now appear for the first time. For many of the facts contained in the sketch of the late Professor Adams, I am indebted to the obituary notice written by my friend Dr. J. W. L. Glaisher, for the Royal Astronomical Society; while with regard to the late Sir George Airy, I have a similar acknowledgment to make to Professor H. H. Turner. To my friend Dr. Arthur A. Rambaut I owe my hearty thanks for his kindness in aiding me in the revision of the work. R.S.B. The Observatory, Cambridge. October, 1895 About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Robert S. Ball (2000). Great Astronomers. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/2298/pg2298-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

Present the life of each astronomer

Great Astronomers by Robert S. Ball is part of the HackerNoon Books Series. Read this book online for free on HackerNoon! : Great Astronomers Title : Robert S. Ball Author : August 1, 2000 [eBook #2298] Most recently updated: October 24, 2010 Release date : English Language Table of Links PREFACE. INTRODUCTION. PTOLEMY. COPERNICUS. TYCHO BRAHE. GALILEO. KEPLER. ISAAC NEWTON. FLAMSTEED. HALLEY. BRADLEY. WILLIAM HERSCHEL. LAPLACE. BRINKLEY. JOHN HERSCHEL. THE EARL OF ROSSE. AIRY. HAMILTON. LE VERRIER. ADAMS. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Robert S. Ball (2000). Great Astronomers. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/2298/pg2298-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

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