Text by CHARLIE NAVARATHNA
Photos by ARCHIVIST LLEWELLYN
"The human species may not be here on earth forever, the arrival of a giant meteor from the asteroid belt could someday end our existence. To have the ability to examine the heavens by using telescopes is a look into the past and the future. We look at Earth's moon and the stars to learn about the space around us and how it relates to our planet below. A question often asked: "What will they find out there?" Those who gave us the invention and development of the telescope have educated us with a rich understanding and contribution to history. These wonderful instruments, the telescopes, open the way to a deeper and more perfect understanding of nature.
Early people knew the sky well and made many observations with their naked eyes. Each group had its own myths about the celestial objects in the sky. Ancient Egyptians built colossal stone structures, precisely aligned to the seasonal risings and settings of the Sun, Moon, planets, and some bright stars.
The earliest devices for "sighting the stars" were crude sticks
Seamen improved these, arriving at a quarter-circle ("quadrant") marked off in degrees, with a sighting arm to measure a star's altitude. Eventually the quadrant was replaced by the sextant (named after one-sixth of a circle, it is actually one-twelfth, doubled with the aid of a mirror). A sextant was the inseparable companion of every navigator until the invention of electronic positioning systems in the late 20th century
The ancient Greeks learned to make precise instruments the ingenious astrolabe. This hand-held device had a moveable arm to measure the angle of a bright star above the horizon, the user could determine time and direction, locate stars in the sky, determine when the sun would rise or set.
Claudius Ptolemaeus Ptolemy lived in Egypt, from approx. 87 to probably 170 AD. Ptolemy was an astronomer, mathematician and He codified the Greek geocentric view of the universe, and rationalized the apparent motions of the planets as they were known in his time. He synthesized and extended Hipparchus's system of epicycles and eccentric circles to explain his geocentric theory of the solar system.
Well do I know that I am mortal, a creature of one day.
But if my mind follows the winding paths of the stars
Then my feet no longer rest on earth, but standing by
Zeus himself I take my fill of ambrosia, the divine dish.
Armillary spheres large and small were used for centuries to study the sky and to teach about the celestial coordinate system, which astronomers used to locate objects in the sky. They were composed of rings (armillae) which represented the great circles of the celestial sphere.
The manufacture and properties of lenses were known since the time of the Greeks. Islamic scholars such as the Egyptian physician Alhazen (born in the 10th century) made important contributions to the study of optics. However, lenses were not introduced to Europe until around the 13th century. By 1300, the first eyeglasses were available in cities such as Venice and Florence, and advances in lens making and polishing soon followed. The tools for making a telescope were therefore available but, for reasons that are not clear, the invention of the telescope had to wait.
The telescope first appeared in the Netherlands
In October 1608, the national government in The Hague discussed a patent application for a device that aided "seeing faraway things as though nearby." It consisted of a convex and concave lens in a tube. The combination magnified objects three or four times. The government found the device too easy to copy and did not award a patent.
Galileo Galilei was an physicist, mathematician, astronomer,and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, Galileo has been called the "father of modern observational astronomy."
In 1668, Isaac Newton devised a reflecting telescope. Instead of a lens, it used a single curved main mirror, together with a smaller flat mirror. In the next century, huge instruments descended from Newton's design turned out to be especially useful for studying very faint objects, such as the dim patches of light known as nebulae. The studies that the new and bigger tools made possible led to fundamental changes in our understanding of the universe.
A variation on the Galilean telescope was suggested by Johannes Kepler in his 1611 book Dioptrice. He noted that a telescopic device could be built using two convex lenses, but the image it produced would be upside down. etc..He found that when he viewed an object directly through such an instrument the image was flipped upside down. But it was much brighter and the field of view much larger than in a Galilean telescope, as Kepler had predicted.
A typical astronomical telescope of this time was the one made in 1656 by Christiaan Huygens, a Dutch mathematician and astronomer, 23 feet long, it magnified objects about a hundred times, and still had a considerable field of view. One of the most spectacular objects that Christiaan Huygens was able to view with their telescope was the great Orion Nebula.
"In the sword of Orion are three stars quite close together. In 1656 I chanced to be viewing the middle of one of these with a telescope, instead of a single star twelve showed themselves (a not uncommon occurrence). Three of these almost touched each other, and with four others shone through the nebula, so that the space around them seemed far brighter than the rest of the heavens, which was enti
rely clear and appeared quite black, the effect being that of an opening in the sky through which a brighter region was visible."
John Hadley was born near London. He showed a talent for inventiveness from an early age, and became a Fellow of the Royal Society at the age of 35, in 1717. Around this time, with help from his two brothers, he began to experiment with the grinding and polishing of metal. Hadley managed to polish his metal mirror so that it had an approximately parabolic shape, avoiding the distortion in previous telescopes with spherical curves. Like Newton, Hadley first showed off his telescope at a meeting of the Royal Society. Records from the meeting say that it was powerful enough to "enlarge an object near two hundred times."
William Herschel, a musician who moved from Hanover to England and turned to astronomy, directed his first efforts toward building refracting telescopes. But the lengthy tubes annoyed him (he made one as long as 30 feet), and he turned his attention to mirrors. By the late 1770s, Herschel had built several reflectors. His most successful one had a 6¼-inch mirror and was 7 feet long. He used this telescope to compile the first substantial catalog of double stars and, in 1781, to discover the planet Uranus. This discovery brought Herschel royal recognition — and an annual salary of £200, which allowed him to practice astronomy full-time. In 1783, using the 20-foot reflector, Herschel began to search the night skies for the dim patches of light in the skies called nebulae. By 1784, he reported that his telescope could resolve individual stars in nebulae previously identified by the French astronomer Charles Messier and that he had also found hundreds of new nebulae.
The 19th century saw an expanded scope for telescopes using lenses
Lenses (refractors) became the professional astronomer's most important tool in the 19th century. As optical technology improved, the refracting telescope became a rugged and precise instrument. It was well suited for the research interests of scientists, who were mainly concerned with accurately measuring the positions and relative movements of stars.
The first observatories built in the U.S. were equipped with telescopes from Europe. George Ellery Hale was perhaps the greatest American science entrepreneur of his time. He inspired, organized, and helped find funding for three of the most important observatories in the history of astronomy. In 1892, the 24-year old Hale was a recently married associate professor at the University of Chicago. Hale's ambition is reflected in the architecture of Yerkes Observatory. The giant 40-inch telescope was not centrally located in the observatory but in a dome off in one wing. Much of the observatory's floor space was laboratory space.
The next generation of optical telescopes
Edwin Powell Hubble was an American astronomer. He profoundly changed our understanding of the universe by demonstrating the existence of other galaxies besides the Milky Way. He also discovered that the degree of redshift observed in light coming from a galaxy increased in proportion to the distance of that galaxy from the Milky Way. This became known as Hubble's law, and would help establish the theory that the universe is expanding. Named in honor of Hubble, the Hubble Space Telescope (HST) is an optical space telescope that was deployed into orbit in April 1990 by the crew of space shuttle Discovery (STS-31).
The next generation of optical telescopes are anticipated to produce even better images than those of Hubble and their aim is to see much farther into space, so that astronomers can learn more about the Big Bang and the origins of the universe. The James Webb Space Telescope is scheduled to launch in 2014; the Giant Magellan Telescope will be built in Chile and the Thirty Meter Telescope on the Mauna Kea summit in Hawaii are both scheduled to be completed by 2018.
Learn more about Telescopes in Second Life
Birr Telescope in SL
Known as "The Leviathan of Parsonstown" in its day, and the Birr Telescope today, the 72 inch Telescope has been reproduced in Second Life, much as a refirbished version of the real life telescope, along with a science center, stands today. The Birr Telescope is a tribute to the third Earl's skill in engineering and optics: the results he obtained with it are a remarkable it was used to discover the first spiral galaxy, and several more after that.
This year is "the 400th anniversary of Galileo's first telescope and was designated The International Year of Astronomy 2009. The Astronomy 2009 sim is part of the all-year celebration. What better way to celebrate the history of the telescope than to make a replica of one of the most famous ones in history?" said enthusiast of science history, Troy McConaghy (Troy McLuhan in Second Life).
Lord Ross Leviathan in SL
W.M Keck Observatory
In the middle of the Pacific Ocean, Hawai’i Island is surrounded by thousands of miles of thermally stable seas. The 13,796-foot Mauna Kea summit has no nearby mountain ranges to roil the upper atmosphere. Few city lights pollute Hawaiian night skies, and for most of the year, the atmosphere above Mauna Kea is clear, calm and dry. From the summit of Hawaii’s dormant Mauna Kea volcano, astronomers at the W. M. Keck Observatory probe the local and distant Universe with unprecedented power and precision.
Their instruments are the twin Keck Telescopes—the world’s largest optical and infrared telescopes. Each telescope stands eight stories tall, weighs 300 tons and operates with nanometer precision. The telescopes’ primary mirrors are 10 meters in diameter and are each composed of 36 hexagonal segments that work in concert as a single piece of reflective glass.
Keck Observatory in SL
Star Gazer Telescopes
Jenika's Astronomy Park Telescopes has many scripted and highly detailed telescopes. Visit the astronomy park and view over a hundred space objects through Second Life's more advanced scripted telescopes! Each telescope contains 99 images including planets, moons, asteroids, comets, open star clusters constellations globular star clusters, galaxies and more. A menu system allows you to easily select which images to display. Telescopes shown in first photo of article.
About the author/photographer
Charlie Navarathna is of Native American ancestry. Archivist Llewellyn is a professional librarian and archivist specializing in science archives. Both are volunteers for NASA Virtual CoLab in Second Life.