Wednesday, June 25, 2014

Framed Filament

Sunspots Surround Filament

It was cloudy for nearly a month since my last solar observing session, and the Sun was almost featureless. But conditions were promising on the morning of June 7th. Forecasts predicted no clouds or wind. The wind prediction was correct, but there were many high thin clouds, often from jet contrails. I decided to set up my telescope anyway. There were many gaps among the clouds, and lots of sunspots had recently blossomed. I'm glad I persevered because the seeing was about as good as it gets.

Sometimes, by luck alone, random factors coincide to yield high quality initial telescope alignment. This was my lucky day! The Sun was almost perfectly centered on the eyepiece crosshairs after the telescope was first commanded to slew to the Sun.

I was set up and ready to observe by 9:00 am but had to wait 15 minutes for a cloud to pass over the Sun. Once I began recording video clips I could see how steady the air was. Detail in the following images is as good as I can ever expect to get. There were no spectacular prominences on display, but five sunspot groups surrounded a dramatic c-shaped filament centered on the Sun's disc.

The first image below is a 15-image mosaic, made with a 2X Barlow lens. Arrayed diagonally above the central dark filament, from left to right, are sunspots 2082, 2079, and 2077. Below and left of the filament are two active areas: 2080 nearest the filament, and 2085 to the lower left of 2080. (Click on the images below for a larger view.)
Sunspots frame the filament very nicely! Here's another mosaic, this time made from 10 images, showing a closer view of this pretty group of features.
The large, c-shaped filament, surrounded by sunspots in the previous two images, lasted for many days. A week after I took these pictures the filament had grown longer and rotated onto the Sun's western limb where it became a huge prominence hanging above the limb.

Since the air was so steady, I tried making magnified images of some individual sunspots with a 5X Barlow lens. First, here is sunspot 2079:
Next is sunspot 2082:
Finally, here are the incredibly complicated sunspots 2080 and 2085:
One side of these sunspots is a north magnetic pole and the other side is a south pole. The nearly parallel curved dark lines stretching between opposite magnetic poles make magnetic field lines near the sunspots visible.

Tuesday, June 17, 2014

Ground Bees

Bee Invasion

When days grew warmer in late March I began noticing little mounds of dirt resembling ant nests on bare patches of ground around my new house. Each small pile had a 6 mm hole in its center. Before long these nests were multiplying at an alarming rate, not only on bare ground, but also in my sod lawn, and even in pine bark mulch in front of my house. The holes were burrows dug by ground bees. Soon these bees were buzzing around everywhere. Clouds of them hovered and randomly flew back and forth near the nests. The pictures below show just one group of nests on one patch of bare ground next to my house. There were many, many more nests in other places around my house.
Fortunately, these bees were not very aggressive. When I mowed my lawn and walked directly into a bee cloud, they seemed to avoid me instead of bouncing off my body, or stinging. The bees, apparently, only nest like this for a month or so and then go away. (Where do they go?) By late May they had disappeared leaving only some ruined mounds behind.

Monday, June 9, 2014

Meteor Bust

Wasted Opportunity

Experts predicted a strong meteor shower, possibly a meteor storm, for the predawn hours of May 24th. A comet named 209P/LINEAR had left behind a trail of debris, and the debris cloud was predicted to encounter Earth between midnight and dawn on the 24th. If predictions were correct, this would be a spectacular event, one I didn't want to miss. 

I woke up after midnight and checked sky conditions at about 1:30 am. After living for years with views blocked in every direction by trees, it's great to be able to walk into my new yard and see an unobstructed view of the whole sky! Clouds covered the southern sky while the north was clearing. By the time I began observing at 1:53 am the whole sky had cleared. The celestial curtains had opened. Let the show begin! Conditions were perfect: no Moon, no clouds, no bugs, a light breeze, and temperature in the low 60's. I sat back in a reclining lawn chair and waited for "shooting stars", pillow under my head, flashlight and notepad beside me, and counter in hand.

The first meteor streaked overhead at 2:08 am, but, sadly, only four more had appeared by 3:30 am. This was certainly no meteor storm! It definitely didn't yield the 30 to 60 meteors per hour I've previously observed during other true meteor showers. How disappointing! What a wasted opportunity! Conditions were perfect, and I was extremely comfortable. Usually, the best viewing locations are in remote places on the opposite side of Earth, but this time even my geographical location was optimal. All the pieces were in place for an epic event, except the event itself.

This is a good time for a minor rant about media hype. Experts predicted a zenith hourly rate somewhere between 100 to 400 meteors per hour. The zenith hourly rate (ZHR) is what an observer would count under extremely idealized conditions.  First, in order to count meteors at the ZHR an observer would have to see the entire sky in all directions at once from one horizon to the other. No single observer can look in all directions at once. Second, to count meteors at the ZHR the radiant of the meteor shower, the point in the sky from which meteors seem to originate, would have to be directly overhead at the zenith. This is rarely ever the case in practice, and was definitely not the case for the predicted May 24th meteor shower. Third, to count meteors at the ZHR the sky would have to be as cloudless, Moonless, and ideally dark as an isolated, high altitude desert site. Such ideal conditions are rarely available to the typical observer. So the ZHR is an idealized upper limit, not a realistic meteor count any observer should expect to see. An actual observer would do well to see half or a quarter of the ZHR.

So how did headlines about the meteor shower appear in the media? They consistently exaggerated and misled the public about what they could expect to see. If a range of values was possible, the headline writers picked the highest value: "400 Meteors Per Hour Tomorrow Night!!!" The ABC Evening News cluelessly shouted, 1,000 meteors per hour! I don't know where they came up with such an outrageously incorrect number. This ignorant misinformation sets up enthusiastic novice observers for disappointment.

Turns out there was a real meteor shower. The experts correctly predicted the encounter of comet debris with Earth, but they didn't correctly predict the brightness of the meteors. Apparently, the cometary debris was smaller than expected. This caused the meteors to be very dim, just below the threshold of visibility to human eyes. The meteors were there, but only visible to radar. 

After 3:30 am I gave up looking for meteors. Instead, I tried photographing the Milky Way, clearly visible toward the south. Even though, miraculously, no street lights or porch lights were in my direct line of sight, the effect of neighborhood lights can still be seen on the houses visible in the picture below. In spite of the surrounding light, the "teapot" of the constellation Sagittarius is visible as well as dark dust clouds in the Milky Way. This image is a 30-second unguided exposure taken at ISO 1600 with a tripod-mounted Nikon D40 camera.
I'm sadly convinced night time observing will be frustrating here at my new home. Once all the vacant homes near my back yard are occupied, it will be almost impossible to find a night where all back porch lights and house window lights are turned off. It's so discouraging to go out on a clear, dark night and have my eyes immediately stabbed by glaring lights from every direction. There's no escape from light pollution it seems.

Sunday, June 1, 2014


Physics Memories

I recently read a history of Einstein's theory of general relativity. Among the names of many scientists who made important contributions to the theory were those whose books and papers I read during my career. In some cases, I had seen these physicists in person and attended their talks. Although physics was my life before retirement, I've now left it almost completely behind. Reading about the development of general relativity evoked strong memories of my own intellectual journey, made me briefly nostalgic about my former life, and motivated this autobiographical post.

How I loved relativity theory! Relativity was my specialty. Relativity was the reason I chose to make physics my profession. The initial spark was struck by something my father said during a big family dinner when I was a boy. We sat around my Polish grandmother's dining room table admiring a huge steaming bowl of homemade pierogies. My father, who must have been reading a popular article about relativity, said, "If we could understand time, we could understand everything." For some reason this pronouncement captured my attention and started my life-long quest to study time. Later, when I learned Einstein's theory of relativity held the key to understanding time, I wanted to learn this theory. I also heard the myth that very few people were smart enough to understand relativity. Learning about relativity, I thought, would not only bring me a deeper understanding of time, it would also be a test of my intellectual capacity.

So I took lots of math and physics courses in college. My initial encounter with relativity during sophomore physics yielded only shallow understanding. By senior year, however, I had learned enough mathematics and solved enough problems to gain some intellectual maturity. I began studying relativity on my own. Between regular classes and assignments I spent every spare minute in the library studying tensor analysis and introductory general relativity. I had switched my major from electrical engineering to physics, and did my senior research project in general relativity working with Dr. Ronald Gautreau helping him investigate the meaning of certain solutions to Einstein's equations. It was intoxicating to know I was the only undergraduate at my college working in general relativity.

In graduate school I continued the quest. Gautreau recommended Temple University where I could work with the resident relativity expert, Dr. Peter Havas. At Temple I was in a bigger league, but really a minor league, like AAA baseball. Princeton, the major league, had rejected my grad school application. That was a good thing because I would not have survived at Princeton. Honestly, I wasn't smart enough for Princeton. It's not that I didn't try. I spent years filling page after page with calculations trying to find solutions to Einstein's equations. My work resulted in stacks of paper a few meters high. This is no exaggeration. When I eventually discarded these calculations, they filled more than one garbage can to full height! Einstein's equations, the basic equations of general relativity, are ten, simultaneous, coupled, nonlinear, partial differential equations virtually impossible to solve without simplifying assumptions. I tried my hand at making clever original assumptions. None of my assumptions worked. It was exhilarating to be working with such high powered theory, but disappointing to have so little success.

The original plan was to work with Havas at Temple, but I found him to be intimidating and unapproachable. He had swept back silver hair and a German accent. His favorite game was destroying colloquim speakers with devastating remarks at the talk's conclusion. Havas would say things like: "Vell, from ze first  sentence of your talk I can see zat you don't even understand Newton's First Law!" Havas knew I was interested in relativity, and he knew I wanted to work with him, but if we approached each other head on in a hallway, he would not acknowledge my existence. If we happened to be in the men's room alone together, he would not even nod or say hello. I couldn't imagine working with such a cold mentor. (Imagine my anxiety when he was appointed to my thesis committee and when he participated in my oral exam.) Instead, I worked with Dr. Mael Melvin who researched cosmological applications of general relativity. Melvin was a bit eccentric, but, compared to Havas, Melvin was friendly, patient, and sometimes encouraging.

Melvin set me working on my doctoral thesis, an investigation of possible universes filled only with neutrinos. The actual universe is filled with matter and energy, and its evolution is described by the equations of general relativity. I investigated an imaginary model universe filled only with neutrinos, a situation that might have been relevant at some time in the past. Melvin suggested using a relatively obscure mathematical formalism that expressed general relativity in terms of three-dimensional vectors and dyadics instead of the usual four-dimensional tensors. Three years of laborious calculations later I produced a thesis titled: Homogeneous Cosmologies with Strong Neutrino Fields, a title that often provokes laughter.

Sometime during my final year in grad school Melvin took me to a talk at Princeton. After the talk we went to a conference room and sat around a table with relativity geniuses on Mount Olympus. There I sat for an incredible hour in the inner sanctum of relativity. I was introduced to the famous John Wheeler, who had worked with Niels Bohr and taught Richard Feynman. Wheeler shook my hand. He graciously asked me a question about my thesis. I mumbled some reply. I was completely overwhelmed by the high-powered intellects present and could barely speak. That was the zenith of my career as a general relativity researcher.

I learned a lot in grad school. Along with a deeper understanding of the mathematical structure of relativity theory I also learned my place in the intellectual pecking order: I was smart enough to understand and appreciate relativity theory, smart enough to work with the mathematics, but not smart enough to make important original contributions to research. I was smart enough to appreciate genius, but not smart enough to be a genius myself.

In grad school I learned theoretical physicists working in general relativity were not in high demand. A more practical career path, a more employable specialty, would have been experimental physics focused on properties of materials. But I was completely, utterly, uninterested in the properties of molybdenum, so I stayed with my first love, relativity.

In grad school I learned how survival at a research university requires constant publication, continual cultivation of reputation, and repeated acquisition of funding through research grants. Strong self-confidence and persistent salesmanship are required in order to obtain research grants. Important people must be impressed enough to award money, employment, and opportunities. Grant proposals are really elaborate ways of proclaiming, "I'm wonderful, and the spectacular work I do is fundamentally important." To me, this seemed like bragging. It conflicted with my personality. Aggressive self-promotion and immodesty are unseemly to me.

Fortunately, in grad school I also discovered some talent for teaching. So, instead of following the usual route of postdoctoral research appointments after grad school, I applied for teaching positions at small colleges. It was a brutal job market for new PhD's at the time. Thank goodness I was lucky enough to find a position at Randolph Macon Woman's College (now Randolph College). It was exactly the right place for me, although I was a one person department, completely overwhelmed preparing and teaching almost every course in the undergraduate physics curriculum and running the college observatory as well.

During my first few years at Randolph Macon Woman's College I tried to keep working on general relativity. I published a paper based on my thesis and studied gravitational waves over the summers. Gravitational wave calculations produced more stacks of paper several inches high. In December, 1980 I had a revelation at the 10th Texas Symposium on Relativistic Astrophysics in Baltimore, MD. While attending talks there I realized I didn't know a single person at the meeting. I was completely outside the loop. At one particular talk the empty seat beside me was suddenly occupied by the famous Kip Thorne, one of John Wheeler's genius students and a distinguished expert on black holes. A bolt of insight hit me as I glanced at him. Kip Thorne and his fellow relativity geniuses were not only much more talented than I, they were also not teaching five courses a semester like I was. They were working year round with high-powered colleagues. I could never keep up with them or hope to compete on their level. In that moment I understood I was an undergraduate physics teacher, not a relativity researcher. I gave up any hope of original research in relativity and devoted the rest of my career to teaching.

Through years of teaching I learned more about relativity than ever before. My conceptual understanding increased greatly because I had to craft clear explanations for students. Two of my strong students did senior honors projects in general relativity under my guidance. It was nice to visit my old intellectual stomping grounds with these students. After retirement my long, slowly diminishing dance with relativity came to an end.

During this long dance I gained profound insights:
  • I can still feel the wonder of first understanding the relation of gravity to reference frame acceleration. It was similar to hearing Chopin's Prelude 13 for the first time.
  • It was a thrill to understand how the fundamental nature of gravity is not its value at a single point, but how it varies from point to point.
  • I was astounded to learn how application of the Principle of Relativity to quantum mechanics led to the incorporation of particle spin and the prediction of the existence of antimatter. Antimatter actually exists!
  • It was great working through the mathematical description of black holes. These exotic objects were predicted by general relativity, and they actually exist!
  • Gravity governs the overall evolution of the universe, and general relativity is our best description of gravity. General relativity predicted the observed expansion of the universe.
  • I spent many hours thinking about time travel and exploring the amusing paradoxes it can include. Time travel to the future is actually possible and has been observed! Time travel to the past is another story.
  • Near the end of my career I came across a profound insight: time is not an observable in quantum mechanics! There's something very deep here, but I'm not the one to figure it out.

My dance with relativity is definitely over. At this point my burnt out brain is a smoldering, smoking ruin. I'm no longer able to run a 5-minute mile, see clearly without glasses, or do any work in general relativity. But I still remember what it was like.

Here's a very brief, incomplete, and very superficial look at Einstein's famous general relativity field equation:
This equation, written on one line, is really shorthand notation hiding a mountain of complex mathematics. The Greek letter subscripts, called indices, can each take on 4 different values. So Einstein's equation is really a shorthand way of writing 16 different equations, ten of which are independent. Also, most of the symbols themselves are shorthand names. For example, the R symbol, called the Ricci Tensor, describes the curvature of spacetime. It is defined in terms of other symbols as follows:
The symbols after the last equal sign on the right, called Christoffel Symbols, are, in turn, defined in terms of the metric tensor, the g symbols, as follows:

Perhaps you can see how writing out all the terms on the left hand side of Einstein's equation would quickly spread across many sheets of paper. In fact, the entire left hand side of Einstein's equation can ultimately be expressed in terms of the g symbols. Solving Einstein's equations means solving for the g symbols. This is the mathematical jungle I staggered through for many years.

People say I'm crazy doing what I'm doing
Well they give me all kinds of warnings to save me from ruin
When I say that I'm o.k. well they look at me kind of strange
Surely you're not happy now you no longer play the game

People say I'm lazy dreaming my life away
Well they give me all kinds of advice designed to enlighten me
When I tell them that I'm doing fine watching shadows on the wall
Don't you miss the big time boy you're no longer on the ball

I'm just sitting here watching the wheels go round and round
I really love to watch them roll
No longer riding on the merry-go-round
I just had to let it go

John Lennon