Like shards of shattered glass caught in a spotlight, the stars appear deceptively passive in the night sky. Yet, each one is an object of extraordinary ferocity. Stellar surface temperatures can reach 50,000 degrees Celsius- over ten times hotter than our Sun – and on a few it can reach over one million degrees! The heat within a star reaches even higher levels that typically exceed several million degrees – enough to tear apart atomic nuclei and transform them into new types of matter. Our casual glances upward not only fails to reveal these extreme conditions but it only hints at the enormous variety of stars that exist. Stars are arranged in pairs, triplets and quartets. Some are smaller than Earth while others are larger than our entire solar system. However, since even the nearest star is 26 trillion miles distant, almost everything we know about them, including those in the accompanying picture, has been gleaned only from their light.
Continue reading “Astrophoto: The Cocoon Nebula by Dan Kowall”
If the universe extends forever and if it’s full of stars, why is the night sky dark? This is a question that has been asked by philosophers and scientists since Antiquity. Johannes Kepler sought an answer, as did Edmond Haley, many years after him. Just as an observer sees trees in all directions when standing in a forest, every line of sight in an infinite universe should end with the twinkling of a star. The net result should be a sky ablaze with heavenly light. Not only should the night sky be as bright, if not brighter, than during the day but the heat from all those suns should be sufficient to boil the Earth’s oceans away! Therefore, the starry scene depicted in the striking picture that accompanies this article, should appear to be missing stars when compared to gazing into the Cosmos above.
Continue reading “Astrophoto: NGC 3324 by Brad Moore”
The ability for convex and concave transparent objects to enlarge or reduce had been known since Antiquity and by the end of the thirteenth century; quality glass was relatively inexpensive, particularly in Italy. At the same time, techniques for grinding and polishing had reached a high state of relative precision in Venice. So, handheld magnifying glasses became relatively common. During the fourteenth century, the craftsmen of Venice began producing small double-sided convex glass disks that could be mounted and worn in a frame- the first reading glasses. By the middle of the fifteenth century the Italians were also producing spectacles that corrected for nearsightedness. Therefore, around 1450 the ingredients to produce the first telescope were in place but it would be another 150 years before children would trigger its invention and change everything.
Continue reading “Astrophoto: NGC 7048 by Stefan Heutz”
Our home galaxy, the Milky Way, is estimated to have 400 billion stars, give or take 200 billion, but less than 6,000 (also an estimate) are visible from dark locations without telescopic aide- and only part of this number can be seen during any single night. Some are dim but close, others are bright but remote and many are partially hidden behind veils of dust so their splendor only hints at their distance. Therefore, the placement of the stars and their brilliance in the sky creates a completely random distribution of bright pinpoints overhead that people have, nonetheless, grouped into familiar patterns called constellations. This affinity for recognizing or imagining designs also extends to the objects in space that can only be seen through telescopes or in photos with long exposures such as this article’s featured picture that, many believe, resembles a flower.
Continue reading “Astrophoto: The Iris Nebula by Tom Davis”
Prior to 1957, virtually all photographs of the sky were produced as monochrome, black and white images. In that year, Ansco, once the world’s largest supplier of professional films, papers, and photo chemicals, introduced Super Anscochrome and over the next twenty-four months, full color images of the heavens were being released by the larger observatories. Over the years technology has improved and the colors captured in astronomical imagery have become more vivid and meaningful. For example, the hues seen in the accompanying picture represent not only this scene’s true-to-nature pallet, but it also reveals what you are looking at, too.
Continue reading “Astrophoto: Stellar Nursery NGC 7129 by Bob Allevo”
Arc lights had been used in lighthouses for several years when Thomas Edison began seeking a way to improve them. Arc lamps use two rods of carbon arranged so that their tips are almost touching. When sufficient electricity is sent to each, the current jumps between them and causes the carbon to become incandescent. Although carbon burns very slowly, over time the rods erode and have to be replaced. The year was 1881 when Edison embarked on a solution and the result of his success spread around the globe to both light and inadvertently curse the darkness.
Continue reading “Astrophoto: Star Trails over Namibia by Josch Hambsch”
Evidence of Astronomy has been found in most ancient cultures. The Egyptians, the Babylonians, the Mesopotamians, the Chinese- and in the New World- the Mayans, the Aztecs and the Anasazi all tracked the movement of stars across the heavens. Astronomy has always been a practical endeavor arising from a fundamental need to anticipate the seasons. Astronomy’s utility didn’t stop there, however. Interpreting the motion of the stars also helped the traveler in ancient and not so ancient societies- particularly those hunting far from familiar landscapes, journeying on long trading missions or sailing out at sea without landmarks. But, in each of these long ago civilizations, what became of the individuals who made the fundamental astronomical discoveries that future generations have taken for granted?
Continue reading “Astrophoto: Fleming’s Triangular Wisp by Steve Cannistra”
For many years, there were three popular theories that tried to explain why Earth’s satellite hangs in our skies. One postulated that the Moon separated from Earth during our planet’s formation, another stated that it was captured when passing close by, and the third held that it formed in place with our planet out of the same material circling the Sun at the solar system’s birth. Each of these ideas had their own justifications but none of them provided all of the answers because each of them were well conceived, but, educated guesses.
Continue reading “Astrophoto: Plato and the Alpine Valley by Mike Salway”
Every clear evening, as twilight dissolves into night, untold thousands of telescopes scattered across the globe turn toward the great beyond that lies above. But, increasingly, a camera is replacing the eyepiece as the favorite way to study the heavens. Taking deep space pictures was once the purview of a small, dedicated group of amateur astronomers. The technology available was daunting, expensive and time consuming. Luck was an important factor in producing an image that resembled its subject. But all that has changed in the past few years- producing deep space images, such as the one seen here, while still not a point-and-click exercise, has become much easier.
Continue reading “Astrophoto: The Bubble Nebula (NGC 7635) by Karel Teuwen”
Stars arise at the heart of great interstellar clouds that have collapsed under their own weight. These free-floating clouds are comprised principally of hydrogen, the most common element in the universe, plus a smaller amount of dust from previous generations of suns. The size of a typical cloud is so enormous that it takes light many years to travel from one end to the other. The amount of material within an interstellar cloud is also staggering to imagine- so much material is brought together that multiple star births are common. Seen from the outside, a collapsed cloud can appear dark and foreboding. But, inside they are full of light from the hot, newly formed stars that have been incubated. Over time, the cloud will part or dissipate to reveal a new group of stars, similar to the two clusters seen in the accompanying picture.
Continue reading “Astrophoto: NGC 6755 and 6756 by Bernhard Hubl”