Universe Today

June 29, 2009December 24, 2015 by Mark Mortimer

Book Review: Keep Watching the Skies

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We work hard to put food on the table and a roof over our heads. If lucky, we’ve got some time left over for other activities. Patrick McCray’s book “Keep Watching the Skies – The Story of Operation Moonwatch and the Dawn of the Space Age” is the story of a program that took advantage of some of those spare hours. During its time, this program had people encouraged, organized, and trained to view the skies and contribute to the nascent space age.

In McCray’s book, the reader gets transported back to the heady days of the mid 1950s when anything seemed possible. Martians could land, asteroids could impact and enemies could lob projectiles across the skies. But, governments had no capability and scientists had no clue as to how to detect any intransigencies. Hence, the call went out for civilian volunteers to watch for transits. With enough volunteers spread across the world, then we’d have the ability to know where, when and perhaps what has briefly streaked across the inky blackness.

As a well written book by an historian, there’s lots of interesting detail within. McCray lays out the basis for the Moonwatch program by including many references to the global politics of the day, whether McCarthyism or socialism. In addition, he gives a cross section of societal attitudes, principally being civic duty and a near adoration of science and technology. Expanding upon this, he goes into the personalities: especially Fred Whipple of the Smithsonian Astrophysical Observatory who set the basis for the program, Len Campbell who acted as the voice of the program, and the many volunteers, such as Vioalle Hefferean who used their time and abilities to scan the skies. Out of this mix comes an entertaining and detailed assessment of everyday talents and the enthusiastic amateurs who were so enthralled with the safety of their nation and contributing to hard science.

This later concept overrides the theme of the book. Though the book is principally a review of a scientific program, it’s also a valuable insight into how amateurs and professionals relate. For instance, some amateurs showed their capabilities to be as good as or better than the professionals. And some professionals wouldn’t support amateurs, no matter how beneficial. As such, this book can provide a reader with some significant insight into the interactions of these elements of society. Also, it shows a fascinating change from almost universal public support for technology toward disregard or disfavour. In it, the reader sees just how flighty public support really is. But, as a history of the little known Operation Moonwatch, this book makes a pleasant, detailed and well referenced story.

The dawn of the space age brought a whole new realm of space science immediately and forcefully into people’s consciousness. Some rebelled at this new perspective, but many were drawn into this wondrous realm. In Patrick McCray’s book “Keep Watching the Skies – The Story of Operation Moonwatch and the Dawn of the Space Age“, this scientific field gets shown for the pure delight that could be derived from participating and contributing even without being a scientist.

June 29, 2009April 26, 2016 by Nancy Atkinson

Landforms Indicate “Recent” Warm Weather on Mars

Retrogressive scarps with cuspate niches, long branching spurs and associated fluvial-like tributary channels. Credit:NASA/JPL/UofA

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Remember the polygon-shaped landforms at Mars north polar region that the Phoenix lander studied? The polygons are produced by seasonal expansion and contraction of ground ice, and these shapes have been found in other regions on Mars as well. New studies of images from the HiRISE camera on the Mars Reconnaissance Orbiter indicates that the Martian surface near the equator experienced freeze-thaw cycles as recently as 2 million years ago. This means Mars had significantly warmer weather in its recent past, and has not been locked in permafrost conditions for billions of years as had been previously thought.

The HiRISE images show polygon-patterned surfaces, branched channels, blocky debris and mound/cone structures.

Dr. Matthew Balme, from The Open University, made the new discovery by studying detailed images of equatorial landforms that formed by melting of ice-rich soils, such as the polygons, branched channels, blocky debris and mound/cone structures. These are all found in an outflow channel, thought to have been active as recently as 2 million to 8 million years ago. Since the landforms exist within, and cut across, the pre-existing features of the channel, this suggests that they, too, were created within this timeframe.

Full resolution view of domed polygons from HiRISE. Credit: NASA/JPL/U of A

All of these features are similar to landforms on Earth typical of areas where permafrost terrain is melting.

“The features of this terrain were previously interpreted to be the result of volcanic processes,” said Balme. “The amazingly detailed images from HiRISE show that the features are instead caused by the expansion and contraction of ice, and by thawing of ice-rich ground. This all suggests a very different climate to what we see today.”

This also means as the shorter the time period since the last warm weather on the planet, the better the chance that any organisms that may have lived in warmer times are still alive under the planet’s surface.

“These observations demonstrate not only that there was ice near the Martian equator in the last few million years, but also that the ice melted to form liquid water and then refroze,” said Balme. “And this probably happened for many cycles. Given that liquid water seems to be essential for life, these kinds of environments could be a great place to look for evidence of past life on Mars.”

Source: STFC

June 28, 2009December 24, 2015 by Mark Mortimer

Book Review: How To Live On Mars

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With all the probes recently landing on Mars, it’s no wonder we feel that the planet is close enough to vacation there. Robert Zubrin has such a scheme already in place for his book entitled “How to Live on Mars – A Trusty Guidebook to Surviving and Thriving on the Red Planet“. Though vacationers are welcome, he much more expects the arrival of immigrants who are ready and raring to put spade into ground for a homestead of the future.

Even though people have yet to land on Mars, our probes peer down, crawl upon and drill into all parts of the Martian surface. From them, we’ve a good understanding of the atmospheric make-up, the surface composition and likely sub-surface material. And, results indicate that people could exist on that planet, but it would be anything other than a comfortable existence. At least at the beginning.

Though the future’s not certain, Zubrin’s book takes the possibly optimistic view of a wise Martian resident providing glimmers of hope for new immigrants. Using an active, present tense, his book dollops up words and ideas of wisdom, such as selecting an appropriate space suit, deciding on the best location for a space hab, and fine-stepping through bureaucratic shenanigans. A humorous slant on the decision making and a slight bend toward technical details make the reading fun and informative. Occasionally, the reader may forget that the book’s proverbial vantage point occurs sometime about a hundred years in the future.

Were this book only providing a light and possible view of human activities in the future, it would have made for a very enjoyable read. But, Zubrin can’t seem to resist throwing darts and arrows at apparently favourite targets of NASA, big business and government bureaucracy. An occasional jab would have grounded the book into mainstream opinion. But, Zubrin takes every issue in the guide book and glamorizes his decision at the expense of “the charlatans of NASA” and corrupt governments. Thus, even though the perspective is from the future, the book seems a critique of the present.

Yet, Zubrin has a lot of experience in the space field, including living at a Mars analog. This experience comes alive in the book, whether from the viewpoint of people on Mars who soar with flying chickens or who safe habitation modules from marauding goats. And yes, with a lot of people on Mars, there will be need for governments and some corruption will likely exist. After all people aren’t perfect. But, we still have to get there, and reading this book may help place us all a little closer to living upon that not so far away planet.

Once we have the vehicles to carry our bodies to Mars and once a substantial number of people live there, then we will need guidebooks on how the rest of us can join in. Though perhaps jumping the gun a bit, Robert Zubrin’s book “How to Live on Mars – A Trusty Guidebook to Surviving and Thriving on the Red Planet” presents one particular view on people’s needs to living on that little red speck that we see in the night sky. Perhaps with more people imagining our presence there, then we won’t have to wait so long for the eventuality to occur.

June 27, 2009December 16, 2015 by Stephanie Bender

What is the Lithosphere?

The Earth's layers (strata) shown to scale. Credit: pubs.usgs.gov

According to the United States Geological Survey (the USGS), the lithosphere is, “the solid outer zone of the Earth comprising the crust and the upper layer of the mantle.”

Also, according to the USGS, the term comes from the Greek word, lithos, meaning, rock, and the word, sphere, which can be any round object, such as a ball, an orange, or, even, you guessed it, a planet.

Wasn’t that helpful? To a Geologist, a scientist who studies the Earth, maybe; but, for us mere mortals, not really. When I think of, “Crust,” I think of the top of a pie. Apple’s my favorite, but anyway, back to the topic. Other times, I think of a loaf of fresh-baked, piping-hot bread, right out of the oven, smothered with honey butter. Oh, it’s so good! Wait a minute! What am I doing? OK, OK, let me make this point so I can forget about food.

When we discuss, “The Earth’s crust,” we’re talking about the outer layer of the Earth’s surface. This is part of the lithosphere. The crust’s made from 3 different types of rock: Igneous; sedimentary; and, metamorphic. Igneous rock forms when cracks in the Earth, known as fissures, break open or a volcano erupts. Both events bring hot, molten rock, known as magma, to the surface, where it cools and becomes different types of rock; what types may depend upon what else mixes with it, how much pressure it’s under, or how much time passes.

The magma, comes from the other part of the lithosphere. It’s released from the upper portion of the mantle. The lithosphere’s responsible for the renewal of the Earth’s surface. When the magma’s released, it becomes known as lava. Other types of rock might be present when the lava arrives; and, since intense heat, pressure, or both can change the rocks from to another, the crust might appear very different afterwords. Some rocks are melted down entirely, and their molten remains may return to the mantle. Eventually, those remains will make another appearance; but, when, or in what form, when all is said and done, who can say?

The lithosphere is very important to the rock cycle. Without it, our planet wouldn’t change. I remember the horrible eruption of Mount St. Helens. The devastation, looked like pictures from Japan, after the atomic bombs hit Hiroshima and Nagasaki; but, I recall hearing later that scientists discovered never-before-seen plant life due to the changes the particles underwent from the pressure, high heat, iron content, and their quick ability to adapt. Like our hearts, the lithosphere keeps our Earth young and healthy.

Universe Today has some other great articles, if you want to learn more about this or similar subjects. One excellent resource is, Earth, Barely Habitable?. Another is, Interesting Facts About Planet Earth.

June 27, 2009December 24, 2015 by Mark Mortimer

Book Review: To a Distant Day

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Being part of a series on a “people’s history of spaceflight”, Chris Gainor’s book entitled “To a Distant Day – The Rocket Pioneers” relives the onset of humankind’s age of rocketry. Though starting from a broad, distant vantage point that includes Galileo and Copernicus, this book quickly jumps to Tsiolkovsky and other recent rocket luminaries. Then, it speedily presents the wondrous people and their amazing effort that led to human spaceflight.

In keeping with being a people’s history, this book compliments the individuals involved and maintains a positive attitude to all segments of aerospace development. As well, Gainor has done his homework, as the book includes a broad swath of detail and still branches a little off the normal path. For example, it includes finer details like Kondratyuk’s mysterious name change, the German Raketenflugplatz group and the Manhigh balloon program. Sometimes the book wanders a bit too far, as when it discusses the origination of Murphy’s Law. But, it’s these additions that would keep this book interesting to the casual, non-technical reader.

Were history simply a recitation of the facts, then this book admirably fits the bill. It includes most of the common space lore and a list of sources that reflect its role as popular history. From these, a reader can appreciate the huge effort expanded to make us a space faring species. But, the purpose of an historical analysis is to find relevance to today. The book includes tidbits in support of this, such as billing space as an empty canvas, free of social problems and ready for exploitation. And it pronounces the dramatic shift in the method of advancement, from a lonely creative genius to a broad, team based effort. However, these perspectives are few and have no discussion on their relevance to today. Thus, as entertaining and informative as it is, this book fails to add to the existing broad reviews of the history of the rocket pioneers. However, it does provide a very nice encapsulation of the advancement of rocketry leading up to the first human spaceflight.

For someone who hasn’t much background in rocketry and who has a casual interest, Chris Gainor’s book “To a Distant Day – The Rocket Pioneers” is a great resource. As it aptly states, with the great efforts of many people across a broad range of technical fields, “Poyekhali!” (as Gagarin said, “We’re off!”).

June 27, 2009December 24, 2015 by Nancy Atkinson

Spirit Rover Begins Making Night Sky Observations

The bright streak is the star Canopus. Credit: NASA/JPL

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When your rover has abundant energy but can’t go anywhere, what’s a scientist to do? How about making observations of the evening and night skies on Mars? With the benefit of a boost in electrical power from a wind gust cleaning off her solar panels, the Spirit rover has more energy available than she’s had for a couple of years. But unfortunately, Spirit is stuck in a patch of loose soil in the Home Plate region on Mars. While the engineers at JPL work hard at figuring out how to “Free Spirit” (see the new website dedicated to their efforts) scientists are making observations of her surroundings to aid in the effort to get her out. But there’s also enough power to do additional observations, and astronomy was a logical choice. “Certainly, a month or more ago, no one was considering astronomy with the rovers,” said Mark Lemmon, planetary scientist at Texas A&M University and member of the rover team. “We thought that was done. With the dust cleanings, though, everyone thinks it is better to use the new found energy on night time science than to just burn it with heaters.” Besides, Lemmon added, using all the energy in the daytime might lead to overheating.

The image above was taken on Spirit’s sol 1943 (June 22 on Earth)showing the night sky above her location.

But most of the “stars” in this raw image are not really stars, just hot pixels. “We use long and multiple exposures to make stars stand out,” Lemmon told Universe Today. “We can only see bright stars, looking through the dust, but can pick out most of the major stars in Orion for instance.”

But a star is visible in this image. “That streak in the 1943 images is the bright star Canopus,” said Jim Bell, planetary scientist at Cornell University and lead for the rovers’ Pancam team. “We’re monitoring stars to search for evidence of night-time clouds, fog, and hazes. We’re also occasionally trying to image Earth and Venus as they set in the west after sunset. We’ve had some success, but the twilight sky is so bright we’re still working on tweaking the exposure times.”

Of course, this isn’t the first time Spirit has done astronomy on Mars. She also made night sky observations back in 2005. In an article Bell wrote for Sky and Telescope in 2006 he described Spirit’s astronomy as “stone-knives and bear-skins backyard astronomy–but from Mars!” And certainly, this is exciting to have an additional opportunity to make astronomical observations from the surface of another world.

Spirit's twilight observations from sol 1947. Credit: NASA/JPL

Bell added that the current astronomy campaign with Spirit has many similarities with the one four years ago, and Lemmon said they are focusing on a few different goals for looking at the twilight and night skies.

“The Canopus images may become a regular occurrence, as a way to monitor dust and/or ice in the sky at night–much as we use Sun images in the day,” Lemmon said. “For something like that, we can pick an aim (Canopus, Orion, etc.) and choose filters. We might use color filters to look for any differences that show up, or the clear filter for the most sensitive measurement. Star exposures can go up to 5.5 minutes (compare to 0.1-0.5 sec for a normal day image). We cannot track stars, so they trail after 10 seconds or so–as you see Canopus doing. In longer exposures, hot pixels and cosmic rays show up as points or cluster of light.”

Lemmon said attempting to image Earth and Venus has been challenging. “We’ve imaged both before, farther from the Sun. They are in the twilight, limiting the exposure we can use, and they are in a “bright” part of the sky.”

Lemmon added his personal favorite right now is actually the twilight imaging — not looking at stars but at how fast the twilight glow fades after sunset. “That is proving to be quite helpful in terms of understanding the distribution of dust in the atmosphere –which is closely tied to how weather works on Mars,” he said.

In 2005, the Pancam team was able to capture images of Mars’ two moons, Phobos and Deimos. “They are much brighter and let us use more filters if desired. We may pick this up again. I’m a fan of eclipse imaging, so we would need several quick images to see how fast the moon fades as sunlight is blocked by dust around Mars.”

The moons should start becoming more visible soon, and Lemmon said they will continue to take more images of Canopus and maybe other star fields. The team is not specifically looking for meteors or the orbiters around Mars, but there’s always the prospect of something fascinating showing up on future images.

“We’ve taken some recent images I hope will have new, interesting things in them,” Lemmon said. “But they are still on board the rover so we’ll have to wait and see what they show later.”

Stay tuned!

Link to Spirit’s raw images.

Webpage on Spirit’s 2005 astronomical imaging.

Sources: email exchanges with Mark Lemmon and Jim Bell

June 26, 2009December 24, 2015 by Nancy Atkinson

Manned Solar Plane Will Attempt Flight Around the World

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A man who circled the globe in a balloon in 1999 has a new global adventure planned. Bertrand Piccard has unveiled a prototype of a solar-powered plane he hopes to fly around the world. Until now, only unmanned solar airplanes have been flown, but Piccard’s HB-SIA would be manned. The glider-like plane has solar panels covering the wings, and the wingspan of the prototype reaches 61m, while the entire vehicle weighs only 1,500 kg. The first tests of the plane will be done to prove it can fly at night. Piccard says he wants to demonstrate the potential of renewable energies.

Piccard just unveiled the prototype, and he hopes to attempt a flight across the Atlantic by 2012.

Solar and battery technology is just now maturing enough to enable solar flight. In 2007 the UK defence company Qinetiq flew an unmanned aerial vehicle called the Zephyr unmanned for 54 continuous hours during tests.

But Piccard and his company, Solar Impulse are working on what they believe to be a breakthrough design, using super-efficient solar cells, batteries, motors and propellers to get it through the dark hours and composite materials to keep it extremely light.

Although the vehicle is expected to be capable of flying non-stop around the globe, Piccard will in fact make five long hops, sharing flying duties with project partner Andre Borschberg.

“The aeroplane could do it theoretically non-stop – but not the pilot,” said Piccard told the BBC. “We should fly at roughly 25 knots and that would make it between 20 and 25 days to go around the world, which is too much for a pilot who has to steer the plane. In a balloon you can sleep, because it stays in the air even if you sleep. We believe the maximum for one pilot is five days.”

More info on Solar Impulse.. And just for your interest, here’s an article about the biggest plane in the world.

Source: BBC

June 26, 2009April 26, 2016 by Mark Mortimer

DVD Review: Sputnik Mania

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Fear remained in the air even after the great global conflict of World War II ended. This arose because, rather than ushering in peace, the cessation of hostilities brought a new fear, the cold war. The History Channel’s 2 DVD set entitled, “Sputnik Mania” shows just how fear permeated throughout the society of the United States and its impact upon the new technological field of rocketry. Whether being rational or even real, fear is shown to be significant catalyst to our journey to the stars.

Sputnik was an unqualified though somewhat unexpected propaganda success. With the orbiting of this small satellite, as it went beep-beep across the skies, the Soviet Union could claim that they had exceeded the capability of the United States. Further, by exploding a test H-bomb at about the same time, the Soviet Union gave the impression that they could create a nuclear holocaust anywhere in the world. With this as a backdrop, the US population reacted via building bomb shelters, fielding flotillas of massive bombers and belatedly launching their own satellite.

In exploring the apparent mass affliction of fear that seemed to permeate those times, the History Channel dips deeply into many rolls of vintage film footage. Most clips have a recognizable content, though perhaps from a different view. For example, there’s John Glenn talking about visiting the moon, yet it was 4 years before he joined the astronaut corps. Then there’s Sergei Korolev watching one of his R7 rockets roar into space. These provide a technical background, but other clips demonstrate the emotions. Lyndon Johnson is shown as a critic of a weak administration while Dwight Eisenhower is shown as an experienced general with a great dislike for an unwarranted arms race. Intermingled throughout are discussions about using the work of Wernher von Braun, an ex-German military member and concerns about the race riots of Little Rock. Sprinkled throughout are shots of H-bomb tests, huge bombers, and bomb shelters. From this, the film competently shows the effect of fear, propaganda and technology in shaping the political course of the day.

This film’s collection of vintage footage is admirable in its own right. But, it’s also a fascinating perspective of a nation’s anxiety during the years 1957 and 1958. Interesting interviews by luminaries such as Susan Eisenhower and Sergei Khrushchev add a more reflective and personal view of the events. The clip of concerned citizens praying for the life of the dog Laika depicts another aspect of society’s concerns. Yet, the film’s main thrust shows how the two most politically powerful states turned a fear of world destruction into a possibility. In this, it admirably succeeds and leaves the viewer with many questions about political policy, virtues of society and the merits of technical progress. From this perspective, the History Channel has crafted an intriguing, if somewhat selective, view of a nation’s mood while it stood at a crossroads.

Not so long ago, we thought that all objects of the universe revolved around Earth. In a very short time, we’ve learned that the Earth is not nearly so unique, but does uniquely keep us alive. Rockets and satellites paved the way for this knowledge and they also paved the way for people to easily destroy each other. This fear, as well replayed in the History Channel’s DVD entitled “Sputnik Mania” shows what might have driven us to such an extreme. And it reminds of where we may end up without due diligence.

June 26, 2009December 24, 2015 by Tammy Plotner

Happy Birthday, Charles Messier!

Most of us know the name of Charles Messier, the French astronomer and comet hunter who published perhaps one of the most celebrated catalogs of astronomical objects of all times, but how much do you really know about the man? Today is the anniversary of Messier’s birth, so why not step inside a take a look a what make this curious astronomical character one of the most celebrated observers of all time.

Charles Messier was born on June 26, 1730, the tenth son in a wealthy family of 12 children from Lorraine, France. Times were very tough back then… Even for the rich. Half of his brothers and sisters died while Charles was still quite young. By the time he’d reached 11 years old, Charles father had also died, but he was left in the care of his 24-year old brother – Hyacinthe – a Navy curator. As luck would have it, while his brother was gone, young Charlie would fall from a window in his house while playing and break the long bone in his thigh. Well, medical attention then wasn’t the same as it is today. A neighboring farmer took him in and cared for him as best he could, writing to Hyacinthe that the lad would have full recovery. However, when the older Messier brother returned, he realized how impaired this injury had made him, so he removed him immediately from the local school, took care of his education, and trained him for eight years for administrative and methodical work. Although we can imagine that young Charles felt a bit restricted during that time, what he learned would serve him well – precise observing methods and an eye for fine details.

Charles Messier was bitten by the astronomy bug at age 14 when a a great 6-tailed comet appeared and he had a chance to witness an annular Solar eclipse from his home town on on July 25, 1748. About a year later, his schooling would end and like most young men, he’d drift for awhile, not too sure of what direction he wanted life to take him. Well, in 1751, that part of present-day France was reorganized, (Off with their heads, you know…) so Hyacinthe decided to stay loyal to a certain faction and it was time to put 21 year old Charles to work. There were two positions open: one with the curator of the palace and one with the astronomer. Guess which position he took? So, on September 23, 1751 Charles Messier left for Paris to work for the Naval Astronomer in the unheated hall in the Royal College where his fine handwriting netted him the job of copying maps. Besides that, the Observatory director, Delisle, kinda’ liked him… So he taught him about his instruments, how to make observations and introduced him to his assistant and they both let him keep their notes.

As an astronomer, Charles Messier’s first documented observation was of the Mercury transit of May 6, 1753. Delisle himself had introduced Messier into the beginnings of astronomy and drove home the point of calculating exact positions of all observations and documenting them. This well-learned lesson was a skill that would eventually immortalize Messier’s observations and in 1754, he was officially employed as a Depot Clerk of the Navy.

And still dreamed about the stars…

Somewhere in 1757, Charles Messier started looking for comet Halley. The comet was expected to return in 1758, but at the time these orbital calculations were little more than guesswork. Observatory Director Delisle had calculated an apparent path where he expected comet Halley to appear and young Messier drew up a star chart for him. As luck would have it, there was an error in Delisle’s calculations and no matter how valiantly and determined Messier was to find the comet, it was never there. At least until the night of August 14, 1758 when he accidentally tripped across another comet. Carefully documenting his observations, Charles followed it telescopically until November 2, 1758 and after comparing notes with contemporaries, realized this particular comet had been discovered on May 26, 1758, by De la Nux. Even if it wasn’t Comet Halley, or a new discovery, his observing time wasn’t wasted… It was the beginning of a new era.

While he was documenting and following De la Nux’s comet, Messier discovered another comet-like patch in Taurus on August 28, 1758. Being the good observer that he was, he recorded its position, returned later, and when he discovered it wasn’t moving – realized he’d located a nebula. He measured its position on September 12, 1758, and it later became the first entry in his famous catalog, Messier 1 or M1. Realizing he was on to something, Messier then began to sweep the heavens with his telescope, searching along Delisle’s path for comet Halley and recording objects “which could be mistaken for comets” along the way.

Comet Halley was finally recovered by German amateur astronomer, Johann Georg Palitzsch, on Christmas night 1758. However, for Messier, his “Ah ha!” moment wouldn’t come until January 21, 1759, nearly a month later. Although he remained loyal to his teacher, Messier began to have doubts about Delisle’s computations, and after a few independent observations he found Comet Halley on his own. Of course, Delisle wouldn’t admit that he was wrong. He told Messier to continue to observe along the lines he’d given him and simply refused to announce his discovery to the French academic world. Like all good employees, Messier simply took it in stride, stating: “I was a loyal servant of M. Delisle, I lived with him in his house, and I conformed with his command.” When Delisle finally realized the error and announced Messier’s recovery of Comet Halley on April 1, 1759, the other French astronomers believed they were a victim of an April Fool’s joke and didn’t believe it. To make matters worse, Delisle even refused to publish another of Messier’s comet discoveries made in early 1760…

Well, 28-year old Messier might have had a weak leg, but he had one heck of a strong back bone, because despite the ridicule and suppression, he became more determined than ever to prove them wrong about his abilities. Delisle was getting old and less inclined to observe… Allowing Messier to take over more and more. Messier recorded his second “nebula,” M2, previously discovered by Jean-Dominique Maraldi, and plotted it on a chart showing Comet Halley’s track. He observed the transit of Venus of June 6, 1761, and the appearance Saturn’s rings. He observed Comet 1762 Klinkenberg from May to July, 1762, and on September 28, 1763, he discovered Comet 1763 (Messier), and the next one, Comet 1764 Messier, on January 3, 1764. He had hopes to enter the French Royal Academy of Sciences in 1763, but it was a dream that didn’t come true… and a bitter let down for Charles Messier.

While searching for nebulae during 1770, Messier went off the beaten path. This led to 19 original discoveries that weren’t documented in any catalogs by other astronomers he could get in touch with. Devoting his life to astronomy, he used every clear night to advantage, continuing to discover comets and add objects to his catalog. At age 40 he married (after 15 years of dating), and a year later, on January 10, 1771, Messier independently co-discovered the Great Comet of that year. On February 16, 1771 he presented the first version of his Catalog of Nebulae and Clusters of Stars, with the first 45 objects, to the Paris Academy of Sciences. This was his very first memoir and during that same year that he was finally officially made the “Astronomer of the Navy”.

A year later Madam Messier gave birth to a son… And within two weeks they were both gone.

If you think today’s scandal sheets at the grocery store checkout are bad, then know they couldn’t hold a candle to what aristocracy could do back then. According to research, a malicious legend is reported by Jean-Francois de Laharpe, written in 1801, that the death of Messier’s wife had prevented the discovery of another comet which would have been his thirteenth, and Messier was more desperate because of the lost discovery than of the death of his wife (especially as this comet was discovered by Montaigne, whom he didn’t like). Anyway, Messier observed this comet March 26 – April 3, 1772. On April 5, 1772, he added another cluster to his list, M50. But after that, Messier seemed to lose his spark for observing and a great deal of his life’s work went on to his assistant, Pierre Mechain. It would be some five years before Messier would take his observing back up in earnest – and 10 years before his passion for hunting comets would return again.

It was about this time that another famous astronomer (Sir William Herschel) began to make his mark in astronomy – and with his superior telescope, put the aging Messier and his work into the past. In less than a year’s time, Charles would accidentally fall once again – this time a 25 foot drop into an ice cellar – from which it took the 50-year old over a year to recover from his injuries. When he returned, he went back to scanning the skies for his beloved comets, but his heart really wasn’t in it. He did discover several more comets, and went on to write many great works. Mechain left to become the director of the Paris Observatory and France fell once again. (Off with their heads). His fortune gone and his observatory falling apart, Charles Messier finally received national attention when Napoleon himself, in 1806, presented him the Cross of the Legion of Honor – the medal you see him so proudly wear in all his portraits.

As time passed, the old man Messier did as many old men do… Retired on their laurels and perhaps spent a bit too much time reflecting on the past. Unfortunately, Charles spoiled a great deal of his astronomical reputation by writing a rather detailed autobiography, which ended up tying the great comet of 1769 to Napoleon, who had been born that year. Even though in his mind, it might have been a good political move, it was suicide to the scientific world. No one could believe he would actually equate the appearance of a comet with Earthly events. As Admiral Smyth said: ‘The last comet put astrologically before the public by an orthodox astronomer’. Quietly going blind, Messier suffered a stroke in 1815, and lived for another two years… to meet the age of 87.

Although you may argue that Messier’s Catalog was not particularly scientific… It wasn’t arranged by Right Ascension and Declination… Nor was it broken down by object type… What Charles left us was a legacy. Within the Messier List is every known type of object: galaxy, globular cluster, open star cluster, supernova remnant and planetary nebula. His observations were made with a small telescope that averages out to about what a modern 102mm would be today. He couldn’t resolve things. He made mistakes. He was human.

He was Charles Messier.

June 26, 2009December 24, 2015 by Nancy Atkinson

Past Climate Change Cannot Be Tied to Earth Passing Through Galactic Plane

The latest map of the Milky Way shows only two arms. Credit: NASA/ Spitzer Space Telescope

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Earth’s climate has changed over time, but the cause for the changes has been hotly debated. One idea (Shaviv and Veizer,2003), suggested that perhaps two-thirds to three-fourths of the variance in Earth’s temperature over the past 500 million years may be attributable to when our solar system passes through the spiral arms of the Milky Way galaxy. The evidence seemed to fit: there appears to be a 140 million year cycle of global climate change, and that correlates when our solar system seems to move between spiral arms, too. Or at least it used to. Since 2003 we have revised our map of the galaxy, which changes the estimation of when Earth transits through the spiral arms.

“Although previous work found a correlation between the 140 Myr climate cycle on Earth and the intersection with spiral arms,” write researchers Adrian Melott, Andrew Overholt, and Martin Pohl, “with new data on the structure of the galaxy, this correlation disappears.”

On Earth, the 140 million year cycle is estimated from the timing of ice ages and abundances of fossils.

The basic idea of the earlier research was that when the solar system journeys through the Milky Way’s spiral arms the event rate of cosmic rays in the Earth’s atmosphere greatly increases, since the number of supernovae in spiral arms is clearly much larger than in between the arms. This could affect cloud formation on Earth and therefore strength of greenhouse effect.

But that assumed the Milky Way had four arms, and was less massive than new calculations show. In 2008, new information from the Spitzer Space Telescope helped astronomers conclude that the Milky Way consisted of two spiral arms and a large central bar. Additionally, in 2009 Spitzer data helped scientists conclude that our galaxy is much more massive than originally thought, and is moving faster than originally estimated.

Red vertical lines represent the midpoints of the last seven ice ages, which don't correlate with the passage of the solar system through the galactic plane. Credit Melott, Overholt and Pohl.

So just when has Earth passed through the galactic arms? With changing estimations of mass and smaller number of arms, no one can be absolutely sure. But Melott and his team have compared the times of transit between regions of the new galactic map with changes in Earth’s climate and found that the 140 million year correlations no longer apply.

The team also says the 140 million year cycle cannot be made to match up with any cyclical movement of the solar system through the galaxy.

“The only periodic trend that can be found with the new data is the relative orbital period of our solar system,” the team writes in their paper, “relative to the previously assumed pattern speed around the galactic plane, which is slightly larger than 500 Myr. Though one could create varying periodic trends by changing this pattern speed, the orbital period relative to the galactic pattern could never reach the 140 Myr time as this is less than the orbital period itself, meaning the pattern and the Sun would be required to move in opposite directions.”

So, the researchers conclude, the solar system passing through the plane of the galactic arms could have no direct tie with past climate change on Earth.

The team’s paper can be read here.

Graphic caption: Red vertical lines represent the midpoints of the last seven ice ages, which don’t correlate with the passage of the solar system through the galactic plane. Credit Melott, Overholt and Pohl.

Source: arXiv, Technology Review Blog