TOP Ten Most Beautiful Physics Experiments

source:http://mocii.com

Robert P. Crease, a member of the philosophy department at the State University of New York at Stony Brook and the historian at Brookhaven National Laboratory, recently asked physicists to nominate the most beautiful experiment of all time. Based on the paper of George Johnson in The New York Times we list below 10 winners of this polling and accompany the short explanations of the physical experiments with computer animations.

1. Double-slit electron diffraction

The French physicist Louis de Broglie proposed in 1924 that electrons and other discrete bits of matter, which until then had been conceived only as material particles, also have wave properties such as wavelength and frequency. Later (1927) the wave nature of electrons was experimentally established by C.J. Davisson and L.H. Germer in New York and by G.P. Thomson in Aberdeen, Scot.

To explain the idea, to others and themselves, physicists often used a thought experiment, in which Young's double-slit demonstration is repeated with a beam of electrons instead of light. Obeying the laws of quantum mechanics, the stream of particles would split in two, and the smaller streams would interfere with each other, leaving the same kind of light- and dark-striped pattern as was cast by light. Particles would act like waves. According to an accompanying article in Physics World, by the magazine's editor, Peter Rodgers, it wasn't until 1961 that someone (Claus Jönsson of Tübingen) carried out the experiment in the real world.

2. Galileo's experiment on falling objects

In the late 1500's, everyone knew that heavy objects fall faster than lighter ones. After all, Aristotle had said so. That an ancient Greek scholar still held such sway was a sign of how far science had declined during the dark ages.

Galileo Galilei, who held a chair in mathematics at the University of Pisa, was impudent enough to question the common knowledge. The story has become part of the folklore of science: he is reputed to have dropped two different weights from the town's Leaning Tower showing that they landed at the same time. His challenges to Aristotle may have cost Galileo his job, but he had demonstrated the importance of taking nature, not human authority, as the final arbiter in matters of science.

3. Millikan's oil-drop experiment

Oil-drop experiment was the first direct and compelling measurement of the electric charge of a single electron. It was performed originally in 1909 by the American physicist Robert A. Millikan. Using a perfume atomizer, he sprayed tiny drops of oil into a transparent chamber. At the top and bottom were metal plates hooked to a battery, making one positive (red in animation) and the other negative (blue in animation). Since each droplet picked up a slight charge of static electricity as it traveled through the air, the speed of its motion could be controlled by altering the voltage on the plates. When the space between the metal plates is ionized by radiation (e.g., X rays), electrons from the air attach themselves to oil droplets, causing them to acquire a negative charge. Millikan observed one drop after another, varying the voltage and noting the effect. After many repetitions he concluded that charge could only assume certain fixed values. The smallest of these portions was none other than the charge of a single electron.

4. Newton's decomposition of sunlight with a prism

Isaac Newton was born the year Galileo died. He graduated from Trinity College, Cambridge, in 1665, then holed up at home for a couple of years waiting out the plague. He had no trouble keeping himself occupied.

The common wisdom held that white light is the purest form (Aristotle again) and that colored light must therefore have been altered somehow. To test this hypothesis, Newton shined a beam of sunlight through a glass prism and showed that it decomposed into a spectrum cast on the wall. People already knew about rainbows, of course, but they were considered to be little more than pretty aberrations. Actually, Newton concluded, it was these colors — red, orange, yellow, green, blue, indigo, violet and the gradations in between — that were fundamental. What seemed simple on the surface, a beam of white light, was, if one looked deeper, beautifully complex.

5. Young's light-interference experiment

Newton wasn't always right. Through various arguments, he had moved the scientific mainstream toward the conviction that light consists exclusively of particles rather than waves. In 1803, Thomas Young, an English physician and physicist, put the idea to a test. He cut a hole in a window shutter, covered it with a thick piece of paper punctured with a tiny pinhole and used a mirror to divert the thin beam that came shining through. Then he took "a slip of a card, about one-thirtieth of an inch in breadth" and held it edgewise in the path of the beam, dividing it in two. The result was a shadow of alternating light and dark bands — a phenomenon that could be explained if the two beams were interacting like waves. Bright bands appeared where two crests overlapped, reinforcing each other; dark bands marked where a crest lined up with a trough, neutralizing each other.

The demonstration was often repeated over the years using a card with two holes to divide the beam. These so-called double-slit experiments became the standard for determining wavelike motion — a fact that was to become especially important a century later when quantum theory began.

6. Cavendish's torsion-bar experiment

The experiment was performed in 1797–98 by the English scientist Henry Cavendish. He followed a method prescribed and used apparatus built by his countryman, the geologist John Michell, who had died in 1793. The apparatus employed was a torsion balance, essentially a stretched wire supporting spherical weights. Attraction between pairs of weights caused the wire to twist slightly, which thus allowed the first calculation of the value of the gravitational constant G. The experiment was popularly known as weighing the Earth because determination of G permitted calculation of the Earth's mass.

7. Eratosthenes' measurement of the Earth's circumference

At Syene (now Aswan), some 800 km (500 miles) southeast of Alexandria in Egypt, the Sun's rays fall vertically at noon at the summer solstice. Eratosthenes, who was born in c. 276 BC, noted that at Alexandria, at the same date and time, sunlight fell at an angle of about 7° from the vertical. He correctly assumed the Sun's distance to be very great; its rays therefore are practically parallel when they reach the Earth. Given estimates of the distance between the two cities, he was able to calculate the circumference of the Earth. The exact length of the units (stadia) he used is doubtful, and the accuracy of his result is therefore uncertain; it may have varied by 0.5 to 17 percent from the value accepted by modern astronomers.

8. Galileo's experiments with rolling balls down inclined planes

Galileo continued to refine his ideas about objects in motion. He took a board 12 cubits long and half a cubit wide (about 20 feet by 10 inches) and cut a groove, as straight and smooth as possible, down the center. He inclined the plane and rolled brass balls down it, timing their descent with a water clock — a large vessel that emptied through a thin tube into a glass. After each run he would weigh the water that had flowed out — his measurement of elapsed time — and compare it with the distance the ball had traveled.

Aristotle would have predicted that the velocity of a rolling ball was constant: double its time in transit and you would double the distance it traversed. Galileo was able to show that the distance is actually proportional to the square of the time: Double it and the ball would go four times as far. The reason is that it is being constantly accelerated by gravity.

9. Rutherford's discovery of the nucleus

When Ernest Rutherford was experimenting with radioactivity at the University of Manchester in 1911, atoms were generally believed to consist of large mushy blobs of positive electrical charge with electrons embedded inside — the "plum pudding" model. But when he and his assistants fired tiny positively charged projectiles, called alpha particles, at a thin foil of gold, they were surprised that a tiny percentage of them came bouncing back. It was as though bullets had ricocheted off Jell-O. Rutherford calculated that actually atoms were not so mushy after all. Most of the mass must be concentrated in a tiny core, now called the nucleus, with the electrons hovering around it. With amendments from quantum theory, this image of the atom persists today.

10. Foucault's pendulum

Last year when scientists mounted a pendulum above the South Pole and watched it swing, they were replicating a celebrated demonstration performed in Paris in 1851. Using a steel wire 220 feet long, the French scientist Jean-Bernard-Léon Foucault suspended a 62-pound iron ball from the dome of the Panthéon and set it in motion, rocking back and forth. To mark its progress he attached a stylus to the ball and placed a ring of damp sand on the floor below.

The audience watched in awe as the pendulum inexplicably appeared to rotate, leaving a slightly different trace with each swing. Actually it was the floor of the Panthéon that was slowly moving, and Foucault had shown, more convincingly than ever, that the earth revolves on its axis. At the latitude of Paris, the pendulum's path would complete a full clockwise rotation every 30 hours; on the Southern Hemisphere it would rotate counterclockwise, and on the Equator it wouldn't revolve at all. At the South Pole, as the modern-day scientists confirmed, the period of rotation is 24 hours.

Top Ten Worst Jobs

source:http://science-professor.blogspot.com

10. Library worker: front desk
This job was mind numbing most of the time and I was not allowed to read (in a library!). There were a surprising number of rude people checking out books, but one of the pleasures of the job was that it was easy to get revenge on rude people. For example, one could 'forget' to demagnetize their books, causing the rude people embarrassment and inconvenience when they tried to exit the library. During one particular encounter with an extremely rude person, I dropped her library card down a slot that led only to a drawer immediately below the front desk, but there was no way for the rude person to know this. I screamed Oh no! That slot leads to the furnace in the basement! Your card has been incinerated and you cannot check out these books! I then 'found' the card, but in my confused state, forgot to demagnetize her books. This is why this boring job is the least worst of the list.

9. Dishwasher
This job was not so bad either. It was kind of disgusting dealing with all the leftover food and the industrial dishwasher was loud and the job was boring, but I liked my coworkers.

8. Newspaper deliverer
I delivered newspapers back in the day when this was a job that kids did. I walked or rode my bike in all weather and placed each newspaper in the door or mailbox, depending on customer preference. I collected the newspaper fee each week in person. I had the stereotypical experiences with dogs: that is, I was bitten on more than one occasion, and had to go to the emergency room once for a bad dog bite. The most vicious and insane dogs had names like Angel and Mimi. I did this paper route diligently for years, but it turns out that my mother had put the route in my brother's name, it being more common for boys to have paper routes back then, and he got awards for my work. I am sure that this has emotionally scarred me in some way, but not as much as some of my other jobs.

7. Sandwich maker
This was horrible, but at least it was brief. I worked long shifts with no breaks and was not even allowed to sit down. I had to use sharp objects and machines to slice and dice vegetables and meats. The deli area was extremely hot. After I fainted a few times from exhaustion, I was fired.

6. Babysitter
This was also horrible and also brief. In fact, I only did it once and I hated it. The experience did not start well because it was my mother who made me agree to babysit for two obnoxious twin boys who lived on our street, and I was not happy about being forced to do this. Then, in a bizarre twist of fate, my mother was invited to ride in the Goodyear blimp that very day and to bring a guest. She refused to bring me because I had made a "commitment" and I couldn't break that commitment just because it was the one and only time in my entire life that I was likely to be invited to ride in the Goodyear blimp. So my mother went without me. As the twins shrieked at each other and threw food at me, I vowed never to babysit again.

5. Library worker: book shelver
This was a bad job for three reasons: (1) it was boring, (2) my supervisor had many bizarre rules that were difficult to follow, and (3) the library patrons were dominated by residents of a nearby institution for the mentally disturbed. I worked on some floors of the library that were totally dark unless I turned on the light in an aisle. I was only allowed to have a light on as long as I was in an aisle, and then had to turn it off and walk in the dark to find the next aisle. This was stressful because of reason (3) above. Some of the library patrons thought it was very fun to sneak up on me in the dark and then scream suddenly. Note that I had this library job before the one described in #10, so at this time I did not deserve to be tortured in a library. Also, some of the less stable library patrons thought it was very entertaining to leave razor blades in some of the books I was shelving, as well as disturbing notes. My supervisor did not care about any of this, but she cared very much that I follow the rule about the lights. This was a bad job.

4. Waitress in seafood restaurant
I have nothing good to say about this experience. I worked long shifts with unpleasant people and had to dress like a cooked lobster. Huge buses would arrive and 100 people would want to be served at once. Someone always injured themselves on a lobster and would get mad at me just because they were clumsy and were bleeding on their coleslaw. The bus people would leave a few nickels under their plates as tips. The cooks said lewd and crude things to the waitresses and the manager yelled at everyone. A surprising number of customers were not nice. When I am visiting my ancestral home and drive by this restaurant, I shudder to this day.

3. Cook in awful restaurant
Even worse than being a waitress is working in the kitchen of a bad restaurant. One summer I worked in the kitchen of a restaurant that was run by a man with a really bad temper and questionable rules to increase worker efficiency. For example, he decided that it would save time if we removed burgers from the grill with our hands instead of using implements. If he saw us using an implement, he screamed and threatened us. So we got burned, and then would run into the walk-in freezer and submerge our hands in vats of pickles. The boss soon realized what we were doing and prohibited us from leaving our work station after extracting a burger (by hand) from the grill. Near the end of the summer, he got very angry at me and started telling me that I was a loser who would never amount to anything because I couldn't even do my job well as a cook in this lousy restaurant and that I didn't know anything and that he was so much smarter than I was blah blah blah. As soon as he stopped yelling, I started quoting the beginning of Book I of the Aeneid, in Latin -- at the time, I knew quite a lot of it. He fired me. Has anyone ever been fired for quoting from the Aeneid? It was truly a worthwhile experience (and I had been about to quit anyway).

2. White slave for wealthy insane people
A college friend and I responded to an advertisement for a summer job working for a family that had a house on a certain island off the coast of New England. The family liked to hire college students to "help" with some light housework, occasional child care, and occasional cooking at their summer home. Much time off was promised, and we would be treated like "one of the family" and paid well. Once we were on this island with no way to escape, the nice people of this family informed us that we would do all the cooking, clean the large house from top to bottom every day, and take care of their beastly children (who liked to spit, throw hard objects, and scream if not given their way). Our time off mostly consistent of going along with the family on "fun" outings at which we had to fetch things for them and basically continue to be servants. Soon after arriving, one of the family members had a screaming fit because we had allowed someone to pluck a grape from a bunch of grapes without using the grape scissors. Our pay was docked. On a daily basis, the grandfather would wander into the kitchen, look in the freezer, scream "There's not enough ice! Make more ice!". We would make more ice. Then the grandmother would wander into the kitchen, look in the freezer, scream "There's too much ice! Get rid of all this ice!" and throw it all out. Then the grandfather would wander back in.. (etc.). Our pay was docked. One night there was a storm and a shutter flapped loose. The next day, the eldest daughter yelled at us for not fixing it in the middle of the night. Our pay was docked. And so the summer went. The only member of the family who was nice to us was the youngest daughter, but she was only nice because she had recently joined a cult and walked around in a daze that may well have been chemically induced. My friend and I kept ourselves sane by writing novels in the style of Jane Austen about our experience and the dark secrets that our employers no doubt were keeping in the attic.

1. Farm worker for tragic farm family
In my Youth, I always did well in school and I always loved to read. One might think that my mother would be happy about this, but at some point in my teenage years she decided that I was becoming "too intellectual" and that I needed to spend a summer carrying out strenuous manual labor. I objected to this anti-intellectual plan and I believe I even called my mother a Maoist at some point, and that did not go over well. So, I soon found myself indentured to a friend of a friend of my mother's co-worker's dentist, or something like that. I was not even paid in money. I was paid in vegetables. The farming family consisted of a middle-aged couple, their young son, a grandfather, and another relative of some sort (a young man, perhaps a nephew). The woman of the farming family had recently survived a suicide attempt, and spent her days staring out the window at me. The young son spent his days kicking kittens and puppies and trying to make the large hog eat something that would make it ill (or, even better, explode). The young man had some emotional problems as well, and he liked to jump out from behind tractors and corn stalks to scare me. The grandfather was extremely nice but demented, and every day he told me how to get from the farm to Florida, mentioning every route number in turn, over and over and over. The farmer man was nice but he didn't really know what to do with me, as he was somehow forced to participate in my mother's Cultural Revolution-like experiment to cure me of being so intellectual. So he used to make up jobs for me. I spent two entire weeks walking up and down the rows of corn, straightening any that had been knocked over. I spent an entire week walking up and down the rows of potatoes, crushing potato bugs by hand. I shingled and painted the farm house, even though I had no idea what I was doing. I got heat exhaustion and was constantly on the look out for the disturbed young man who liked to scare me. One day as I lay under a tractor, delirious and nearly unconscious from the heat, I decided to become a professor.

Top 10 Reasons Ron Paul Can Win

source: http://paul4prez.blogspot.com


10. The Internet. In previous elections, if the mainstream media consigned a candidate to the sidelines, he stayed there. Now, thanks to YouTube, Google, discussion forums, blogs, and the ability of readers to comment on major news articles, candidates like Ron Paul can no longer be hidden from public view, and networks of support can develop and strengthen on their own.

9. The falling dollar. Early on, Ron Paul was dismissed by media pundits as the guy worried about details of monetary policy that most voters didn't care about and couldn't understand. After the dollar's precipitous drop this year, Ron Paul's warnings about easy credit and calls for sound money have sparked serious debate in the financial community, and his condemnation of the "inflation tax" has struck a nerve with the voters.

8. Inaccurate polls. Anyone who assumes that the polls are in any way predictive of the results need only look back to 2004, when John Kerry came from way behind to win the Democratic nomination. Besides the oft-noted inaccuracies in polling methodology, the simple fact is that most voters haven't yet decided who they will vote for, and we won't find out until election day.

7. Appeal to Democrats. While the top Democratic candidates won't promise to bring the troops home from Iraq in the next four years, and the Democratic Congress does nothing to protect our fading civil liberties, Ron Paul's strong record against the war and for saving our Constitutional freedoms has already persuaded many Democrats to re-register as Republicans for the primary, and would make him a strong candidate in the general election.

6. Appeal to Independents. While some Republican and Democratic partisans view politics as a game of one-upping the other side and advancing their own agendas, independents are more interested in finding the best solutions to the problems facing the nation, regardless of their source. Ron Paul's willingness to discuss problems at their fundamental level, and to propose solutions outside the usual limits of debate has given him strong appeal to independent thinkers. Independent voters are key to winning early primary states like New Hampshire and Michigan, and will make Ron Paul an even stronger candidate in the general election.

5. Appeal to Republicans. While Ron Paul earns most of his attention for his anti-war stand, he is more conservative across the board than any of the other top Republican candidates. He is solidly pro-life, pro-Second Amendment, pro-smaller government, pro-Constitution, pro-free market, anti-illegal immigration, pro-border security, anti-tax, and pro-freedom. When conservatives seriously consider the issues that matter most to them, they discover that Ron Paul is the only major contender who is consistently on their side.

4. Principled consistency and personal integrity. In an age when flip-flopping candidates like Mitt Romney, Mike Huckabee, and Rudy Giuliani could hold YouTube debates against younger versions of themselves on issues like abortion, immigration, taxes, and the Second Amendment, Ron Paul stands out for sticking to his limited government principles throughout his ten terms in Congress. Voters will support a candidate with unquestioned integrity, even when they disagree with him on some issues.

3. Unlimited funding. The November 5th and December 16th money bombs earned more than ten million dollars for the Ron Paul campaign, but they also delivered something even more important -- the ability to return for another round from more than 100,000 small donors, while the big-money donors of the other contenders are already tapped out. Mitt Romney can keep loaning himself money, but the other candidates can't. If it becomes a national campaign after the early contests, Ron Paul is one of the few candidates who can afford to compete everywhere.

2. Grassroots support in all 50 states. Establishment candidates are accustomed to relying on their advantages in money and media coverage to win in the primaries. Ron Paul's supporters have used the Internet to circumvent those barriers, and to establish a national network of over 80,000 volunteers in over 1,000 cities. If no one wraps up the Republican nomination in the early going, Ron Paul's grassroots network will give him a decided advantage in later contests, and the ability to respond wherever it is most crucial. The political "experts" might be have missed this huge advantage, but Rudy Giuliani knows we're out there.

1. Voter turnout. The main reason that pre-primary polls are so often wrong is that voter turnout is exceedingly low in the primaries, and it is hard to predict who will actually show up to vote. Candidates generating genuine enthusiasm will do much better than predicted, as will those whose supporters are well organized. Have you run into any enthusiastic McCain, Giuliani, or Thompson supporters lately? Anyone questioning the enthusiasm or organization of Ron Paul's supporters needs only to consider his impressive record in party-organized straw polls, or to reflect on why other candidates with supposedly greater support have been unable to organize their own money bombs. Ron Paul supporters will show up on election day.

Top 10 Best-Selling AT&T Ringtones (2007)

the list is:

1. Shop Boyz - "Party Like a Rockstar"
2. Mims - "This Is Why I'm Hot"
3. Soulja Boy - "Crank That (Soulja Boy)"
4. Nickelback - "Rockstar"
5. Akon - "Don't Matter"
6. T-Pain - "Buy You A Drank (Shawty Snappin)"
7. Hurricane Chris - "A Bay Bay"
8. Sean Kingston - "Beautiful Girls"
9. Huey - "Pop, Lock & Drop It"
10. Fergie - "Big Girls Don't Cry"

AT&T offers ringtone download a la carte for $2.99. However, if you're a ringtone nut, you can subscribe to their MyMedia Club for $5.99 and up a month wherein you can get credits to be exchanged for graphics, games and yes, ringtones.

source: http://www.mobilewhack.com

Top 10 Gadget Gifts for Under $50

source: http://blogs.miaminewtimes.com

1. USB Memory Watch – Whoever you give this to will feel like James Bond when they connect their ordinary watch to their office computer only to reveal that it contains that year’s expense report. The watch has two gigabytes of memory. $40.

2. Cocktail Cyclone Portable Drink Mixer CSS-565 – This nifty little mixer does all the work for you. Just pour in and hit the mix button. It looks stylish too. It’s perfect for that drunkie friend or family member. $15.

3. Go Light On My Lips Gloss – For the girl who has to put on lip gloss at all times of day, whether there’s enough lighting to do it properly or not. The base of the lip gloss container has a small LED light that shines just where it’s needed. $38.

4. Jump-Start DC Power Plus – This device will actually jump start your car battery without the need for jumper cables and it has a flashlight. It’s a good gift for that friend of yours who’s car is always stalling. $40.

5. LED Faucet Lights – These lights not only look cool, but they change colors with the temperature of the water. It’s a small gift for that person who wants their bathroom to look futuristic (and who doesn’t). $15.

6. USB Rocket Launcher – A gift for the bored cubicle dwelling office worker. Use with caution, though. It may hit your boss in the eye and get you fired. $35.

7. Plasma Mug – Remember those crystal balls with electric bolts floating around in them (you know you do). Now you can have the same kind of fun with this mug. Be careful though, the mug does not seem like it is shatter-proof so try not to drink too much beer out of it. $25.

8. USB Rechargeable Batteries – While not a gift in and of themselves, these stocking stuffers are perfect for the gadget crazy friend. The batteries charge by connecting the batteries into a USB port on a computer. $18.

9. Solar Powered LED Water Bottle – This gift can serve as a camping light, a water bottle, and a night light for those who need it. It’s solar powered so it’s eco-friendly. $25.

10. Auto Suck – This one can serve as a gag gift or a seriously kinky gift. It simulates road head through powerful suction. Don’t think it’s that safe to use in Miami, doubt you’ll need another distraction on the road. $38.

Top Ten Free and Open Source Legal Issues of 2007

source: http://lawandlifesiliconvalley.blogspot.com

The year 2007 has been the most active year for legal developments in the history of free and open source (“FOSS”). In fact, you would have been hard pressed in past years to enumerate even five important legal developments. However 2007 permits the creation of a traditional “top ten” list. My list of the top ten FOSS legal developments in 2007 follows:

1. Publication of GPLv3. The GPLv2 continues to be the most widely used FOSS license, yet the law relating to software has developed significantly since the publication of the original publication of the GPLv2 in 1991. The first revision of the GPLv2 had a number of drafts over an 18 month period. However the new GPLv3 license is much more comprehensive than GPLv2 and addresses the new issues which have arisen in software law in the last 15 years.

2. SCO’s Attack on Linux Collapses. SCO filed lawsuits claiming that Linux infringed SCO’s copyrights in UNIX. These suits suffered a fatal blow when the court in the Novell litigation found that SCO did not own the copyrights in UNIX. The ownership of the copyrights is essential to prosecute cases for copyright infringement. The melt down of SCO’s strategy was complete when it filed for bankruptcy soon after this loss.

3. First Legal Opinion on Enforcing a FOSS License. In August, the district court in San Francisco surprised many lawyers by ruling that the remedies for breach of the Artistic License were in contract, not copyright. Most lawyers believe that the failure to comply with the major terms of an open source license means that the licensee is a copyright infringer and, thus, can obtain “injunctive relief" (which means that the court orders a party to cease their violation). On the other hand, if the remedy is limited to contract remedies, then the standard remedy would be limited to monetary damages. Such damages are of limited value to open source licensors. The district court decision has been appealed.

4. First US Lawsuit to Enforce GPLv2. The Software Freedom Law Center filed the first lawsuit to enforce the GPL for the BusyBox software in August. Subsequently, it filed three other lawsuits. Although the first three lawsuits were against small companies, the most recent lawsuit was against Verizon. These lawsuits represent a new approach for the SFLC which, in the past, has preferred negotiation to litigation. SFLC has settled two of the lawsuits. Each of the settlements has required that the defendants pay damages, another new development. These suits may be the first of many.

5. First Patent Infringement Lawsuit by Patent Trolls against FOSS Vendors. IP Innovation LLC (and Technology Licensing Corporation) filed suit against Red Hat and Novell in what may be the first volley in a patent war against a FOSS vendor. Acacia is a well known patent troll which has been buying patents for some time and works through multiple subsidiaries. The FOSS industry provides a tempting target because of its rapid growth. These suits could slow the expansion of FOSS because many potential licensees express concern about potential liability for infringement of third party rights by FOSS.

6. First Patent Lawsuit by a Commercial Competitor against a FOSS Vendor. Network Appliances, Inc. (“NetApps”) sued Sun Microsystems, Inc. (“Sun”) for patent infringement by Sun’s ZFS file system in its Solaris operating system. The ZFS file system posed a challenge to NetApps products because it permits the connection of less expensive storage devices to the operating system.

7. Microsoft Obtains Approval of Two Licenses by OSI. Microsoft Corporation continues its schizophrenic approach to FOSS by simultaneously asserting that the Linux operating system violates Microsoft’s patents and submitting two licenses for approval by OSI. In October, the OSI Board approved the Microsoft Public License (Ms-PL) and the Microsoft Reciprocal License (Ms-RL) as consistent with the Open Source Definition.

8. German Court Finds that Skype Violates GPLv2 The enforcement of the GPLv2 in Germany continues with a Munich court finding that Skype had violated GPLv2 by not including the source code with the binary version of the software (instead, Skype had included a “flyer” with a URL describing where to find the source code version). The suit was brought by Harald Welte, who has been the plaintiff in virtually all of the German enforcement actions for GPLv2. Harald runs gpl-violations.org, an organization which he founded to track down and prosecute violators of the GPL.

9. New License Options. Two of the most controversial issues in FOSS licensing, network use and attribution, were addressed in new licenses adopted this year. A “network use” provision imposes a requirement that when a program makes functions available through a computer network, the user may obtain the source code of the program. Essentially, it extends the trigger requiring providing a copy of the source code from “distribution” of the object code (as required under the GPLv2) to include making the functions available over a computer network. An “attribution” provision requires that certain phrases or images referring to the developing company be included in the program. This provision was very controversial on the License Discuss email list for OSI. The Free Software Foundation published the Affero General Public License in the fall which expanded the scope of the GPLv3 to include a “network use” provision. A limited form of attribution was included in the GPLv3. And OSI approved the Common Public Attribution License which included both the “network use” and “attribution” provisions.

10. Creation of Linux Foundation. The Open Source Development Labs and the Free Software Foundation merged to form the Linux Foundation. The FOSS industry is unusual because of the extent to which it depends on non profit entities for guidance. These entities include the OSI, Free Software Foundation, Mozilla Foundation, Apache Foundation and Eclipse Foundation. This merger provides a much stronger platform to promote Linux and open standards.

Top 10 SCADA Security Stories of 2007

Here is our list of the top ten stories rated by immediate and expected long term impact on the community. (See the 2006 list)

1) Aurora

An easy choice for number one. Even though we have had both control system and IT experts give apocalyptic quotes for years on how they could easily take down large parts of the critical infrastructure, nothing prior came close to alarming those outside the community as the video showing a cyber attack cause physical damage in demonstration power plant. Shaking and smoking trumps words.

Reaction in the community was mixed and tilts slightly negative. Our reaction was nothing new here. There are large numbers of vulnerabilities in control systems that combined with process knowledge can cause damage (and without process knowledge can cause denial of service). That said, there is no denying that this has gotten Congress involved, made an impact on control system security coverage in the press, and probably gotten a number of C-level executives asking are we vulnerable to that attack I saw on CNN. Raising awareness is a good thing so in addition to being the number one story, we rate it a net plus for the community.

2) FERC/NERC/Congress and the NERC CIP’s

This top ten list is heavy on electric, but that was where the action was in 2007. FERC has been battling a bit with their ERO (NERC) primarily over lack of response to comments on the NERC CIP’s in December 2006. Lack of response led to a more official set of proposed changes published in a NOPR in July.

Given NERC/ERO’s approved consensus-driven / ANSI standards making process it is difficult to see how this would play out in FERC pulled out the hammer on the ERO. Whatever the result will be, it likely will take a lot of time. Hopefully, NERC/FERC and the Congressional overseers can find some common ground. Our recommendations have been to focus on providing more specific guidance on the existing requirements and developing audit tests with teeth that can be consistently applied.

Heaped on top of this discord was Aurora and Joe Weiss’s advocacy for dumping NERC CIP standards, which led to Congress getting involved in a more serious manner than previous hearings. Congress asks FERC hard questions and you know it rolls downhill. Even after this kerfuffle the NERC CIP train moves down the tracks with compliance requirements coming as soon as Q2 2008.

My guess is this will make the 2008 top ten list.

3) SCADA Presentations at Hacker Events

2007 marked the year when hacker events like DefCon, HITB, and Black and White Ball all included a SCADA presentation. This trend seems to be continuing in 2008. There was no real news made in any of these very basic presentations (some headlines and commotion but no real news) that were made circa 2002 at control system venues. That community is an inquisitive lot, and they will get better.

The obscurity argument continues to fade away, especially on systems purchased this decade.

4) Browns Ferry Incident

So many cyber related control system outages and other incidents remain secret, but NRC reporting requirements brought out the interesting case of a Safety Controller failure causing a Nuclear Plant to be scrammed. A safety VFD controller to stop responding “due to excessive traffic on the plant ICS network”.

Control system security pundits came down in two camps. One believed it was due to poor design of the switching and network infrastructure, and the other believed it was due to a protocol stack error that crashed went sent spurious traffic. We fall in the later camp because we have seen many controller Ethernet cards fail when lightly fuzzed or sent broadcast traffic.

5) Wurldtech, Mu and a dash of ISA

In 2007 Wurldtech Security Technologies introduced their Achilles Certification and Mu Security introduced their MUSIC Certification. Both companies use their test appliances to send thousands of legitimate, illegal and fuzzed packets at a control system device, typically a controller, to test the security and robustness of the protocol stack. To add a little spice to this competition, Eric Byres formerly of Wurldtech, joined Mu’s Advisory Board.

The good news for the community is that controller protocol stacks are getting tested, problems found and corrected, and asset owners have another information point for buying decisions.

Late in the year ISA got involved in the picture with their Automation Standards Compliance Institute (ASCI) Security Compliance Institute (SCI) that has a goal of creating an ISASecure certification program. This is off to a slow start and is looking at a two year timeframe for the first certifications.

Full Disclosure: Wurldtech was a Digital Bond client, and we assisted them in structuring and launching the Achilles Certification.

6) OPC Vulnerabilities

Lluis Mora and the team at Neutralbit sent 25 OPC server vulnerabilities to US-CERT in 2007. The affected vendors are slowly fixing these vulnerabilities which then are disclosed in vulnerability notes, NetxAutomation, Takebishi, and Gesytec.

Do the math. 25 vulnerabilities sent to US-CERT; 3 vulnerability notes; and over 20 OPC vulnerable servers implementations that the vendors have chosen not to fix a year later! Oh by the way, many still argue that we should trust the vendor to disclose and fix identified security vulnerabilities.

Neutralbit has made the tool available on a limited basis so asset owners can test their own OPC server.

7) Initial Steps in Regulation of the Chemical Sector

In 2007 DHS introduced Chemical Facility Anti-Terrorism Standards (CFATS). The current standards have very little to do with cyber security of the chemical plant DCS, about a similar amount as in the old Sandia RAM’s. However this becomes a regulatory vehicle that may be enhanced in the future to include more serious control system cyber security requirements.

Opinions on regulation vary greatly in the community, but it may be a trend to watch in 2008 as we are starting to see more action in Europe in this area as well.

8 Joe Weiss Unfettered

Love him or hate him, Joe Weiss moving from KEMA to form his own company, Applied Control Solutions, and more importantly become Unfettered, is a top ten story this year. Whether it is whispering in a Congressional staffer’s ear or shouting from the rooftops, Joe has significantly changed the NERC CIP debate. It will be interesting to see in 2008 he is successful in scuttling NERC CIP in favor of a ‘better’ standard.

9) Field Security Device Market

There is a saying in business school that there is not a market unless you have two vendors. In 2007 Byres Security and MTL introduced their Tofino field security device which joins Innominate’s mGuard product that has been out for years and sold in the 10,000+ quantity. These products’ primary purpose is a firewall, but they also can include IDS/IPS, VPN and anti-virus.

In October Hirschmann announced they would offer their own field security device rather than private label the Innominate product.

We are still skeptical about the size and viability of this market, but in 2008 we should have worthy products to test the market.

10) SCADA Security Scientific Symposium (S4)

Ok. We are a bit biased and want to give a shameless plug for S4 2008.

After years of frustration in high level, hand-waving, buzzword, 20-minute “technical presentations” dumbed down for a non-technical audience we felt compelled to create an event where researchers can present technical papers in detail to a technical audience. S4 2007 papers included most of the control system vulns disclosed in 2007, secure control system protocols, new security metrics and test methodologies, and methods and algorithms to detect attacks in control systems.

Seriously though, this control system security community is not going to advance unless a published body of knowledge and venues for researchers to discuss and collaborate results is available. If you doubt that, look at how little progress was made 2000 - 2006. I saw the same thing happen in the crypto world in the late 80’s / early 90’s. We already see in the S4 2008 papers that researchers are building on past results in S4 2007 papers. There is still a shockingly low level of worthwhile SCADA security research out there, and we look forward to the day when we are choosing between 50 or 100 respectable S4 submissions.

Top ten albums of 2007

It's that time of year again and in the next few days I'll get around to listing and blurbing what my favourite albums of the year were. But before that here's some albums that I really liked this year that didn't make the top ten but may have. There's no ordering really aside from the sort of random one I had when I made my shortlist of potential top ten records.

LCD Soundsystem - Sound Of Silver


Bon Iver - For Emma, Forever Ago


Deerhunter - Cryptograms


Battles - Mirrored


Dan Deacon - Spiderman Of The Rings


St. Vincent - Marry Me


Okkervil River - The Stage Names


Elliott Smith - New Moon

Top 10 US OOP Books of 2007 (Bookfinder’s)

1. Once a Runner (1978) by John L. Parker, Jr.
The cult classic distance running novel; the long-awaited sequel, Again to Carthage, was released in November
2. Football Scouting Methods (1962) by Steve Belichick
Legendary college football scout’s playbook, used by coaches and players to develop winning game plans
3. Sex (1992) by Madonna
The pop icon’s controversial book of erotic photos
4. Promise Me Tomorrow (1984) by Nora Roberts
An early novel that the bestselling romance novelist refuses to reprint, describing it as “mediocre”
5. The Lion’s Paw (1946) by Robb White
A children’s adventure story about two orphans who travel around Florida in a boat
6. The Principles of Knitting (1988) by June Hemmons Hiatt
An indispensable resource on hand knitting
7. Raven: The Untold Story of the Reverend Jim Jones and His People (1982) by Tim Reiterman
Chronicles the inner workings which allowed the Peoples Temple to flourish
8. Aran Knitting (1997) by Alice Starmore
History and how-to about the Irish knitting technique
9. One Way Up (1964) by John F. Straubel
The story of of helicopters and vertically rising aircraft
10. Dear and Glorious Physician (1959) by Taylor Caldwell
A novel based on the life of Saint Luke

Top 10 Facebook Stories of 2007

To say it’s been an eventful year in the world of Facebook and the Platform would be quite an understatement. 2007 saw the birth of a new way of building and distributing software on the web that spurned on the imagination of entrepreneurs and awoke industry giants. In the future, we may look back on this year as a time of “social networking frenzy” that turns out to be more hype than substance. Or, we may look back on it as a time when the way the people use the Internet changed.

Here’s a look at the top 10 Facebook stories of 2007, as told through the eyes of a product manager in Silicon Valley:

1. Facebook launches Platform, intends to become “social operating system”

On May 25, Facebook unveiled the “Facebook Platform” at f8 in San Francisco. Dozens of apps were showcased from several launch partners. Breaking from the command-and-control approach to third party widgets employed by others at the time, the Platform allowed deeper integration points than any other API, and allowed anyone to sign up and start developing–and keep all the revenue. Hundreds of developers gathered for an all-day hack-a-thon to kick the tires on the new Platform, and by the end of the year, over 10,000 applications had been launched.

2. Facebook Platform becomes the most viral software distribution system ever

Within two weeks, music application iLike added 1.7 million users, making it one of the fastest growing applications on any platform ever. Within three weeks, an astounding 10 applications added over 1 million users each. Software developer Craig Ulliott, creator of the then-side-project Where I’ve Been application, asked, “I have 250,000 users, now what?” as his servers crash under the traffic load. 65 million applications were installed in the first month - an average of 2.5 per user. By December, that number had risen to over 700 million.

3. Facebook user base, traffic numbers soar

After the Platform launched, traffic and new users to Facebook soared: after three weeks, page views increased by a third. The post-college crowd helped Facebook’s reach double from 2006 to 2007. Facebook’s total userbase grew from about 15 million in January to 30 million in July. In December, it stood at about 58 million. Facebook added an average of 250,000 new users per day in 2007.

4. Facebook’s News Feed offers a new paradigm for sharing information (and marketing)

When the Mini Feed and News Feed launched in September 2006, users were concerned by what it meant for privacy. Since then, the News Feed has come to be accepted as one of the most important advances in social networking technology. Facebook filters an average of 30,000 story candidates into a customized stream of 60 stories for each user every day. For social networking marketers, getting into the News Feed has become just as important as getting into the first page of Google’s search results.

5. Facebook Platform creates an application economy

When Facebook announced the Platform, it announced that application developers could keep 100% of the revenues their apps generate. This, in turn, led to a frenzy of early acquisitions and investments. Just a month after the Platform launched, SideStep acquired Extended Info. Shortly thereafter, Slide bought Favorite Peeps for $60,000, the first publicly reported transaction price. Lee Lorenzen starteda trend by making Altura Ventures “the first Facebook-only VC.” In July, Bay Partners launched AppFactory to invest in Facebook application developers. Over the course of the summer, several ad networks were started to sell Facebook application inventory. In September, Mark Zuckerberg announced the formation of the fbFund, a Facebook-affiliated fund specifically set up to deploy grants to innovative application developers.

6. Google organizes OpenSocial, Facebook opens Platform architecture

After failing in its bid to partner with or invest in Facebook, Google announced the OpenSocial API, an open API that would allow application developers to build apps to run on multiple social networks. However, manged by a consortium of companies, OpenSocial has failed to get off the ground due to an incomplete spec, and the first social networks supporting it are not expected to be ready until early next year. Meanwhile, in December, Facebook announced it was opening its Platform architecture for adoption by other social networks, and Bebo launched its platform by announcing it was completely adopting Facebook’s architecture from the start.

7. Microsoft invests $240 million in Facebook at $15 billion valuation

In a major strategic coup over Google, Microsoft won a minority stake and an expanded advertising relationship with Facebook in October. The price? A mere $15 billion valuation - or about 100x TTM revenues. (Facebook execs allegedly played the two off each other masterfully, driving the valuation way up.) Rumors that Facebook also took $500 million from two hedge funds proved to be false, but the company did take $60 million from Chinese billionaire Ling Ka-Shing in December.

8. Facebook backtracks on Beacon

With a splashy launch in New York, Facebook announced several new advertising products for businesses in November. One of them, Beacon, was particularly aggressive: it allowed partner sites to send information about a user’s off-Facebook activity to Facebook for sharing in that user’s News Feed. After privacy advocates spooked advertisers by complaining that the program was opt-out instead of opt-in, Facebook reversed course.

9. Facebook lures top talent

Planning to increase head count to over 700 by the end of 2008, Facebook was able to hire top talent (before its massive valuation increase) in 2007, including some top engineers from Google. Former Googler Justin Rosenstein called Facebook “the Google of yesterday, the Microsoft of long ago,” adding, “I have drunk from the Kool-aid, and it is delicious.” Benjamin Ling, a former Director of Product Management at Google, left for Facebook in October.

10. Facebook courts businesses with Pages and Social Ads

In an attempt to monetize its “social graph” more effectively, Facebook allowed businesses to create a presence inside Facebook for the first time (except for expensive sponsorships) in November with the launch of Pages. At the same time, Facebook launched Pages, a souped-up version of its old Flyers program, which together offer advertisers unprecedented levels of targeting and analytics inside a social network.

source: http://www.insidefacebook.com

Top Ten New Year's Eve Destinations

Here is Yahoo Travel's list of the top 10 most popular New Years Eve destinations which has not been endorsed by Reuters:

1. Las Vegas, USA

Las Vegas bills itself as the world's party capital and on New Year's it hold back no stops. With The Strip filled with revelers, fireworks explode over the hotels and the casinos are packed. The showrooms are filled with entertainers including magician David Copperfield and The Doobie Brothers while nightclubs are hosting a list of celebrities such as Paris and Nicky Hilton and Britney Spears' ex-husband Kevin Federline.

2. New York, USA

On New Year's Eve, hundreds of thousands of revelers crowd Times Square for the famous ball drop from the top of one of the neon-lit buildings which has been a tradition dating back to 1906. Get there early -- and don't expect to be able to leave until the party really is over.

3. Boston, USA

First Night 2008 offers a list of events with New Year's Eve activities taking place from 1pm to midnight on Monday, Dec 31 at over 40 indoor and outdoor venues. Popular attractions include a Family Festival at the Hynes Convention Center, gigantic ice sculptures, a fireworks display, and a Mardi-Gras style procession that sweeps through the streets of Boston.

4. Orlando, USA

Trust Walt Disney not to miss a party. The Walt Disney World Resort rings in 2008 with street parties, longer hours and fireworks galore.

5. Paris, France

Pack a bottle of champagne and some plastic champagne flutes to join the crowds along the Champs Elysees from where you can get a good view of the Eiffel Tower as it explodes in light at the stroke of midnight while other fireworks explode around the city.

6. Cancun, Mexico

For people who love sun, dancing and a lively crowd, Cancun is billed as a top destination for New Year's Eve.

7. Miami, USA

As Miami grows in popularity as a vacation destination, it is becoming a party city at all times of year. A major benefit is the weather outside can be as warm as the party inside.

8. Honolulu, Hawaii

Enjoy a warm celebration in Honolulu where most hotels host big parties.

9. Manila, Philippines

Manila ushers in the New Year with a bang, quite literally, and with parties everywhere. Firecrackers and fireworks begin on New Year's Eve and continue over midnight with the noise, based on Chinese belief, supposed to drive off evil spirits and bring in good luck.

10. Sydney, Australia

New Year's Eve on Sydney Harbour is a spectacular event with boats galore out on the water and crowds holding picnics around the water waiting for the 12 minutes of intense fireworks at midnight. This year audiences will get a display involving 30,000 effects, six barges located across the harbour, eight City buildings and, of course, the famous arches and roadways of the Sydney Harbour Bridge.

Top Ten Astronomy Pictures in 2007

Number 10: A Comet Bursts Forth

I remember when I first heard of Comet Holmes: I’d received an email in October from a BABloggee telling me about it, and I couldn’t wait for the sky to darken so I could see it with my own eyes. Naked eye comets are rare, but a run-of-the-mill faint one to suddenly brighten by a factor of a million; well, that’s a must-see.

People all over the world took pictures of the comet’s outburst (the cause of which is still something of a mystery). For a while, the outburst appeared as a circular shell surrounding the comet, though eventually a more tail-like appearance took shape… but it was still just plain ol’ odd.

This picture was taken on November 29, 2007 by the gifted astrophotographer Tamas Ladanyi (he also has another picture taken on December 5 which shows the motion of the comet, too). This remarkable shot covers several degrees of sky; by this time the comet was getting difficult to see with the unaided eye (it got fainter as the debris cloud expanded), and at the time the cloud was bigger than the full Moon in the sky. I love the starry background in this picture, and the small open cluster of stars on the right.

As I write this, Comet Holmes is still fading away. But will it brighten again? In 1892, just after it was first discovered, Holmes had an outburst very similar to this modern one. So even as it dims and moves into the outer solar system, is it gearing up for another exciting run?

I’ve written quite a bit about this comet, if you want the background info, and I even made a video.

Number 9: A Black Hole on Mars

What is it about Mars that draws us in? Even through a big telescope it’s small, distant, and fuzzy. But when you gaze up on it in the night sky it’s a bright bloody beacon, a glaring eye staring back at you. No wonder the ancients thought it the god of war!

We’ve been exploring the Red Planet for decades now, and we have learned so much about it. Sometime over the past few decades, Mars transformed from an astronomical object to a place, an actual location where we can go and look around.

And even though terabytes of data have been taken, Mars still has a surprise or two up its sleeve.

Update: I had originally described this hole as a skylight to a cavern, but that turns out to be incorrect. I would normally keep the incorrect text here and strike it through so you could see my mistake, but the way I had written it makes that hard. So instead, I’ll simply delete the incorrect text, admit my mistake, thank commenter AJ Milne for pointing it out, and post the correct description!

When I saw this image, my jaw dropped. Other images of the surface showed black spots suspected to be cavern entrances or pits, but they showed featureless black holes. But then I saw this picture, and once again Mars reinforced the idea that it’s a place.

The picture (taken with the HiRISE camera on board the Mars Reconnaissance Orbiter) shows a pit crater, a collapsed shaft going down into the surface of Mars. It’s on the side of a volcano, and similar features are seen in Hawaiian volcanoes. Most likely they form when magma under the surface subsides, and the ground above it collapses.

In this hi-res picture, with the Sun off to the side, we can see rocks and debris littering the floor. It looks like the pit leads to a tunnel off to the right, but that may be an illusion caused by the shadowing. It tricked me at first! But it’s probable that this does not lead to an underground cavern. Still, I’ve stood at cavern entrances in Virginia and Kentucky (and a sinkhole, once) that aren’t too different in appearance from this pit, bringing home the fact that Mars, like Earth, is an actual world.

When I look at this picture my sense of exploration, of wanting to walk into that pit and poke around, is nearly overwhelming. I can’t help thinking that Jules Verne would have felt at home standing at the lip of that crater.

Number 8: The Wonderful

The red giant star Mira is called "The Wonderful" because it brightens and dims noticeably to the naked eye, sometimes going from quite bright to total invisibility in just a few weeks. Mira is a star on its death bed; it is in the final stages of sloughing off its outer layers, and in a few hundred thousand years the entire envelope of the star will have been ejected, leaving only a naked and very hot white dwarf star.

It’s been studied extensively for decades, centuries– but when the Galex spacecraft pointed its ultraviolet camera at the sky near Mira, astronomers got quite a surprise.

Mira is like a comet! But a lot, lot bigger: the tail of Mira is 13 light years (130 trillion kilometers/80 trillion miles) long.

The tail is really the gas ejected by the star as it dies. As Mira moves through space, the gas between the stars slows the ejected material, forming the long streamer. It reminds me of The Little Astronomer’s hair flowing behind her as she runs. But Mira is moving substantially faster than my daughter can run; it’s tooling along at 140 kilometers/second (90 miles/second). It’s taken the star 30,000 years to move the length of its tail. In the picture, the motion is left to right, so the left-hand side of the tail is the oldest. On the right you can actually see the bow shock as the star plows through the gas between stars.

This image isn’t the highest resolution, or the prettiest of the lot. But it has so much to say. Mira is much like the way the Sun will be in a few billion years when its time runs out, for one, so by studying this image we are perhaps peering into our own future. But it also tells us that even a familiar object can surprise us, when we look at it with different eyes.

For far more detail on the story of this remarkable object, read my blog entry on it.

Number 7: The Lover’s Embrace of Arp 87

Galaxies seem like immutable giants of the cosmos; serene, majestic, and unmoving. But that’s an illusion. Everything in space is in motion, including galaxies. As you can imagine, when you take a collection of several hundred billion stars and set it in motion, it can be pretty hard to stop it. Galaxies move through space at numbing speeds, and the forces built up are mighty.

But then, sometimes, another galaxy gets in the way.

Then those vast forces come into play. Gravity twists and pulls at the galaxies as they dance past each other. And, as if they resist the inevitable recession of their partner, they reach out to one another in what looks like a tender embrace, but is in reality a stark (if lovely) portent of the destruction wrought on both galaxies.

Arp 87 is the name given to the system of two galaxies, NGC 3808A and NGC 3808B. They passed each other just as the age of dinosaurs was starting to get going on Earth, 200 million years ago. The gravity of B (the cigar-shaped galaxy on the left) drew out a long tentacle from the much larger A (the spiral on the right), and it appears as if the passage also wrapped the tendril around B, perhaps more than once. It’s also possible the tendril flared out, separating into streams that only appear to entwine the smaller galaxy.

The pair is 300 million light years away, and the power of the Hubble Space Telescope is clear when that forbidding distance is taken in. We can see reddish gas clouds collapsing to form stars in the galaxies, and we can (just barely) tell that NGC 3808B is looking a little disturbed. Will the two galaxies continue to separate, or will gravity eventually win, drawing them together? Perhaps the latter. In a few hundred million years the merged remnant will settle down and look like a normal galaxy once again. And while this may look like a totally alien tableau, keep in mind that the Milky Way Galaxy has suffered through such collisions in the past… and will again: the Andromeda Galaxy is bearing down on us. In a couple of billion years, the fireworks here will begin.

My original blog entry about Arp 87 is here.

Number 6: Lightning at Weikerscheim Observatory

Astronomy only plays a tangential role in this picture… you can see stars in the sky, and the observatory is pretty obvious. But it’s the terrestrial drama that steals the show.

Jens Hackmann took this stunning picture of a lightning storm near the Weikerscheim Observatory; the 300 second exposure is enough to see the stars streak and the observatory lit up by ambient light. Sometimes, when it’s cloudy, observing is difficult… but you can still get incredible pictures.

Number 5: A Meeting of the Moons

Jupiter is fantastically massive, and its fearsome gravity holds thrall over a retinue of moons that might otherwise be called planets in their on right. By far, the most interesting of its family are the moons Europa and Io. Europa is an ice world, covered in a thick sheet of ice that might reach down to depths of over perhaps several kilometers. It’s nearly a dead certainty that underneath that forbidding icecap is an ocean of water, kept liquid from energy input by gravitational stress as Europa passes by her sister moons. Of all the real estate in the solar system, many astronomers have their money on Europa as the best place to look for alien life.

Io, on the other hand, is perhaps the worst place for life. It has an incredibly high sulfur content, for one thing. For another, the same gravitational heating that keeps Europa’s ocean liquid also keeps Io’s interior molten, but it gives the moon a cosmic case of indigestion.

Io is wracked with volcanoes. They are almost constantly erupting, spewing molten sulfur over a kilometer high in the low gravity, and plumes of dust and gas blast hundreds of kilometers off the surface. This activity was first discovered when the Voyager 1 probe passed the moon in 1979, but subsequent space probes have gotten even more detailed images. When the New Horizons Pluto probe passed Jupiter in March 2007 for a gravity boost, it snapped a beautiful picture of the sisters.

Europa is the crescent on the lower left, and Io (obviously) is the one on the upper right. The plume you see is from the volcano Tvashtar, which has been active for quite some time now. If you look right at the bottom of the plume, you can see molten sulfur glowing red. Two other volcanoes appear to be making some noise as well.

While they appear to be close together, the two moons were actually nearly 800,000 kilometers apart when this picture was taken; Io was on one side of Jupiter and Europa on the other, but from the spacecraft’s perspective they were next to each other in the sky. This picture is actually a composite of two images; one was greyscale and had high resolution, and the other was in color but had lower resolution. By merging the two, we can see more details than we could from the color image alone, and we get the benefit of having the colors enhance the scene.

When I first saw this image, I knew right away the two moons were not close together at all. My secret? I saw that the dark side of Europa was truly dark, but Io’s dark side was lighter. That meant that Io was positioned such that Jupiter was illuminating its otherwise dark half, while Europa must have been on the other side of Jupiter, where it was dark. Sometimes, you can tell a lot just by looking at a image and picturing the geometry in your head.

Funny: I almost picked a movie sequence of Tvashtar erupting for this Top Ten list, but I had to cull it due to the other images I liked better. Plus, the animation is 752 kb, and I didn’t want to choke my server. But you can see it on Emily Lakdawalla’s Planetary Society Blog. It’s worth watching!

Number 4: Dark Matter Makes an Appearance

It’s baffling, and a little humbling, to think that what we can see, taste, and feel makes up only a tiny fraction of the Universe. Normal matter only constitutes 4% of the cosmic budget, with dark energy eating up a whopping 73%. The remaining 23% belongs to the mysterious dark matter: some exotic form of material that does not emit light, but does exert a gravitational force. Astronomers knew it was out there for decades; it pulled on galaxies and clusters and galaxies, changing their speeds. We just couldn’t see it!

But the gravity of dark matter has a subtle effect: it acts like a lens, bending the path of light coming from objects behind it. We can use telescopes to map out the location of normal matter, and then measure the distortion of background objects from the intervening dark matter. When that is done, spectacular results emerge.

In this Hubble image, the white dots are entire galaxies. They are part of a cluster called CL0024+1652, which is a whopping 5 billion light years away. The blue glow is the location of the dark matter, revealed by its distortion of the shapes of more distant galaxies behind it. The dark matter is in the shape of a ring surrounding the cluster, which indicates that a long time ago, CL0024 suffered a mighty blow, colliding head-on with another cluster. The dark matter from the two clusters passed right through each other, and their gravity caused the material to form the ring shape. We’re seeing this right down the barrel of the collision.

This image is a stunning confirmation of the existence of dark matter, and our understanding of how it works. Many people — who don’t understand the science — claim dark matter doesn’t exist, and that astronomers are making it all up. Well, there’s a giant smoke ring in the sky indicating they are quite wrong.

However, that’s not to say we understand everything about such events. In a picture I almost picked for the Top Ten, we see evidence that there are holes in our knowledge.

In this composite image of the galaxy cluster Abell 520 using Chandra, CFHT, and the Subaru telescope, red is normal matter heated to millions of degrees, and blue shows the location of the dark matter. The problem is, where the normal matter is densest the dark matter is least dense, and vice-versa. That’s the opposite of what’s expected here. Perhaps dark matter particles interact with each other differently than we think, or there was some odd factor in the cluster collision that’s throwing a monkey wrench into the works.

There’s a lot more about dark matter to learn, and images like these will help us solve these mysteries. Right now there a lot we don’t know… but we’ll figure it out. That’s why astronomy is so much fun.

Number 3: Chaos in Vela

I have long been a fan of Davide De Martin from Sky Factory. He takes images from professional observatories and stitches them together to make images of indescribable beauty, elegance, and wonder. His work is, simply, breathtaking.

This image shows the devastation wrought when a star explodes. The Vela Supernova Remnant formed when a massive star 800 light years away blew up 11,000 years ago. Expanding at a ferocious velocity, it is now 8 degrees across in the sky — 16 times the apparent width of the Moon, and about the size of your outstretched fist! David’s mosaic shows a stunning amount of detail, tracing the variety of shapes and patterns the expanding gas makes as it slams into the interstellar junk floating around it.

And if that’s not enough, the full-size image he has on his site is well over a billion pixels in size. Think about that the next time you brag about your digital camera.

I wrote more about David and his Vela image on my blog.

Number 2: STEREO Eclipse

Technically, this one is not a picture, but I had to include it anyway. It’s just so cool!

Studying the Sun seems like a pretty good idea; as the major source of light and heat for our planet, it’s a good thing that we try to understand it. And the Sun is a star, with all that implies: it’s huge in size, and frightening in its energy production.

To better understand it and the complicated nature of its surface activity, NASA launched a pair of satellites that can take pictures of the Sun simultaneously from different angles, providing a 3D view of our nearest star. They’re called the Solar Terrestrial Relations Observatory, or (haha) STEREO.

One satellite orbits the Sun ahead of the Earth, and the other behind. They stay in the same orbital plane as the Earth does in its travels around the Sun, and that means that sometimes you get interesting geometric situations which arise. The STEREO team realized that there would be a time when the Moon would pass in front of the Sun as seen by one of the spacecraft. Solar eclipses are rare on Earth, but from STEREO’s vantage it would be even more unusual.

From the Earth, the Sun is about 400 times farther away than the Moon, and is also about 400 times the Moon’s physical size. These two characteristics cancel out, meaning the Sun and Moon are about the same apparent size in the sky, so every solar eclipse has the Moon slipping in front of the Sun, with the dark disk of the Moon just barely (if even) covering the bright disk of the Sun.

That is, every solar eclipse as seen from the Earth.

But STEREO was receding from the Earth and Moon. To it, the Moon appeared much smaller than we see it, stuck as we are on the surface of our planet. The Sun, however, was still at about the same distance, and therefore looked the same size as we see it. This means that, to STEREO, the Moon appeared far smaller than the Sun.

Not long after launch, the situation arose that the Moon would pass directly in front of the Sun as seen from one of the spacecraft. STEREO turned its eye that way, and recorded what may be the most remarkable footage of a solar eclipse ever taken.

This sequence shows something we can never see from the Earth: a shrunken Moon passing in front of the Sun. Technically, it’s not even really an eclipse; it’s a transit (when something small crosses in front of something large). That video, only 8 seconds long, is incredible. We see the Sun and Moon literally every day, of course, and it totally shook me to see them look so different.

That’s why I chose this sequence. I love seeing the familiar become unfamiliar, grasping a new perspective on the everyday, the ordinary. You see? There is something new under the Sun.

By the way, STEREO has taken some truly excellent images of the sky, including an astonishing sequence of Comet McNaught.

And the Number One Astronomy Picture of 2007 is…

The Beautiful Face of IC 342

I am a sucker for spiral galaxies, especially ones that are face-on. They are sweeping, majestic, chillingly beautiful, and utterly mesmerizing. There are many such grand design spirals in the sky, and astronomers are almost all familiar with the roster: M81, M51, M101, and others. But there is one that is a bit less seen, less well known. That’s because it hides itself, tucked away in a part of the sky where stars and dust are thick, obscured by the fog of our own Galaxy.

But it is no less gorgeous for being demure.

This creature is IC 342, a nearby spiral lying only 11 million light years away, very close on a galactic scale. If IC342 were located in a region of the sky where our own Milky Way didn’t interfere with the view so much, it would be one of the most celebrated objects in the sky, and would most likely sport a proper name and not just a numerical designation. But because we see it through so much murk, it remains mostly unknown.

What a misfortune! It is a spectacular object. The power of the Mayall 4-meter telescope at Kitt Peak in Arizona reveals the true beauty of this galaxy. Almost all the stars in the image are actually in our Galaxy, much closer than IC 342 (imagine looking out a dirty window to see a bird sitting on a fence to get an idea of what’s going on). But look at it! The arms trace out the births of countless stars, punctuated by glowing red gas as the young stars heat their cocoons. Dark dust lanes hide the stars behind them, mimicking the way the Milky Way dust hides IC 342 itself. You can trace the magnificent arms all the way in to the center, where they meet in a pinwheel of colossal proportions.

In the highest resolution images (click here if you dare!) the picture is even more boggling: you can see far more distant galaxies in the background, some edge-on spirals, and even one ring galaxy. Huge clumps of star-forming regions in IC 342 reveal themselves, and you can spot places where the spiral arms split into separate spurs. Even the foreground stars, so much closer to home, provide a polychromatically spangled vista against which the much more regal spiral lies.

All in all, a devastating picture. The colors, the features, the composition… and it shows us that sometimes, beauty and grandeur can be missed, even when it’s in your own back yard.

source: http://www.badastronomy.com