Happy Birthday Carl Sagan

Carl Sagan was a towering figure in science. He was born on November 9, 1934, in Brooklyn, New York, and died following a long battle with cancer on December 20, 1996, in Seattle, Washington. In between, in just 62 years, he reshaped public understanding of physics, astronomy, and space exploration. More than this, he was a leader in exploration and discovery, involved in many of the scientific teams behind truly ground-breaking space missions in the 1960s and 1970s, including the Apollo moon landings and the Viking missions to Mars.

I first started to encounter Carl Sagan as a popularizer of science while an undergraduate at University of Guelph, and wrote a couple of columns mentioning him for The Ontarion, the university’s newspaper, in the early 1980s. I briefly thought of pursuing grad work on exobiology but ended up continuing along with evolutionary ecology instead, at Guelph for a few more years. His influences are still all around us.

Visit the Carl Sagan Portal to experience a little of this amazing gentleman’s life and contributions: http://www.carlsagan.com/

Hang Out in the Galaxy Zoo

Would you like to contribute to something bigger than yourself? Have a few minutes every now and then, and access to a computer and the internet? You likely do if you’re reading this. If so, you too can help with research that is changing our understanding of the whole cosmos.

Galaxy Zoo is a new form of citizen science. Founded in 2007, the idea was very simple. Wonderful new telescopes and surveys of the sky were generating more information – more photographs of deep space – than the scientists behind the observing programs could possible classify. It’s not enough to just take a photograph of something to discover something new. You have to be able to “reduce” the observations into data – into a form that can be used to describe the scene statistically, or better, to test specific hypotheses.

Hubble Space Telescope image of deep space

An image of very deep space taken by the Hubble Space Telescope. Everything in this image is a galaxy, from foreground to the most distant dot. Credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team. Source: http://hubblesite.org

Telescopes like the Hubble Space Telescope (http://hubblesite.org/), and observing programs like the Sloan Digital Sky Survey (http://www.sdss.org/) have imaged millions upon millions of very distant galaxies in certain areas of the sky. Some of these are billions of light years away. the challenge is that computers – so good at crunching information – are not yet very good at that “data reduction” step. In other words, you and I can look at a photo and tell right away if we’re looking at a photo of an elliptical galaxy (a little fuzzy blob of a thing), a spiral galaxy (a little fuzzy blob with distinct spiral structure), or something unusual (something that doesn’t fit the basic patterns).

So, in 2007 researchers reached out to the Internet – an early “cloud sourcing” exercise – for help. Now in its fourth iteration, Galaxy Zoo (http://www.galaxyzoo.org) lets users like you and me help with the mountain of galaxy images. In just a few minutes of preparation, you’ll be shown a photo of a galaxy and asked about its basic shape. A few other simple questions about what you see follows. All of your responses are taken by Galaxy Zoo by a simple “click on an icon” format. It’s a lot of fun, it’s real science, and some of the little galaxies you classify may never have been seen by anyone else (on Earth, that is). You can come back over and over, classifying more galaxies over time. You can also take on-line quizzes to test your knowledge about the universe.

As of 2012, the science team behind Galaxy Zoo have produced 25 scientific papers on the results of this effort. You can read all about the program, and also find links to the published results, at the Galaxy Zoo web site: http://www.galaxyzoo.org

Jump in! What are you waiting for?


My Favourite Amateur Astronomy News from 2012: September’s Impact on Jupiter

There were some great astronomy news stories in 2012, but one really stands out for me as a demonstration of why amateur astronomy can still be “more” than a hobby. Dedicated amateur astronomers can make real contributions to science.

Early on the morning of September 10, Mr. Dan Peterson was observing the planet Jupiter with a 12″ telescope in Texas, and saw a bright flash on one side of the planet. The flash lasted perhaps 1.5 to 2 seconds, and was reported to be very bright. Mr. Peterson posted his observation on an astronomy web forum (http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5413921/Main/5413225). A few hours later another amateur, Mr. George Hall, posted a photograph of the flash, confirming the earlier report (http://georgeastro.weebly.com/uploads/1/3/3/4/13344093/jupiterimpact.jpg).

This event – likely the impact of a small, previously unknown comet – into the Solar System’s largest planet – would not have been observed at all unless amateurs had seen it, as was the case. With the large number of planets and other interesting objects in our Solar System (especially comets and asteroids), the professional scientific community and the incredible instrumentation provided by earth-based and space-based telescopes can’t monitor everything all the time. There are no spacecraft in the vicinity of Jupiter, and even if there had been, observing an unpredictable event that lasted 2 seconds would be down to sheer luck even if there was a spacecraft near-by.

Even the world-wide network of amateur astronomers can’t catch everything that happens, of course, but the chances are that transient events will be picked up by an amateur first. This isn’t a new situation. The Association of Planetary and Lunar Observers (yes, they use the acronym A.L.P.O. – http://www.alpo-astronomy.org/) has been organizing, recording, and helping people to share observations on the planets, comets, asteroids, and just about everything else in the solar system, for decades. With 14 different “observing sections” covering everything from meteors to remote planets, A.L.P.O. is a great example of people contributing to new knowledge – true citizen scientists. A.L.P.O. even publishes its own journal, in production since the 1940s. Membership is open to anyone interested, whether or not you are making regular observations. They are international and welcome all interests.

There are several ways in which amateurs are contributing to astronomy around the world right now. In addition to observations of Solar System events and the discovery of comets, some are making detailed measurements of the brightness of individual stars over time, called stellar photometry. Many stars are variable, changing their brightness over time for several different reasons. For example, the American Association of Variable Star Observers (http://www.aavso.org/) links up and supports people making observations of stars that are changing brightness because of their intrinsic physics, or even because of orbiting companion stars (occulting binaries).

What’s more, even in today’s light-polluted urban environments, like Southern Ontario, amateur observing programs like these can continue. The moon and the planets out to Saturn, at least, are so bright that useful observations can be made even with the ubiquitous background glow in the sky reducing the contrast of what we can see. Getting involved in a meaningful way in these programs is also not dependent on having large, expensive telescopes. There are observing sections in A.L.P.O. for people observing the sky with nothing more sophisticated than a pair of binoculars, or just their eyes. Knowledge of the sky, patience, and making careful, organized notes are the most important tools any astronomer – amateur or not – brings to the science.

© 2012, David Allan Galbraith

Blogging as a Learning Experience

I’ve jumped into presenting the Pine River Observatory blog as a personal project this month. Now that I’ve a few posts under my belt perhaps a little commentary is appropriate.

I want to be upfront with everyone who’s taking a few minutes to read these posts (thank you, by the way). I am not a professional astronomer or physicist, and I don’t consider myself to be very experienced as an amateur astronomer, either.  Those of you who may know me personally will understand this point, but the question may still be in you minds: why, then, am I putting a blog out there for the world to see? What to I bring to the P.R.O. blog that might be worth-while for others to consider?

Hopefully you’ll be interested in the learning trajectory I have set for myself and may feel like following along.  The blog is a challenge to myself, to set up something that demands my attention and concentration, and that provides me with a chance to develop tools and ideas for my own application in astronomy and astrophotography. Critically, it gives me a ready platform to share some of the products of my creativity, in written and visual forms.

DAG_3075 cropped 1024

Looking north along the shore of Lake Huron toward Kincardine and the Bruce Nuclear Power Plant. A 30 second exposure taken 14 August 2012 at 11:30 PM, ISO 5000, f/3.5, Nikon D800 and 24mm wide-angle lens, with white balance set in the camera to a manual cool setting. Captured were a meteor (top left) and the Pleiades (M45; middle right).

I hope you will also enjoy the images I have been posting, and will continue to prepare and post. I am enchanted with viewing the night sky, and in capturing images of such a sweeping and inspiring nature.

What I do bring to the blog is a life-long passion for science, and a special interest in physics and astronomy that are nearly on a par with my professional fascination with biology and evolution. The two go hand in hand in many ways, and a certain synergy between these great branches of natural science will undoubtably creep into future postings. I envision that this blog will have a somewhat broader basis over time than “just” astronomy; it will not be an on-line log book of my own observations (although it might include such a feature at some point). I will be looking to add context to what I see in the sky, and to events as they unfold in science more generally, and I hope this will make the blog a richer experience for it. I also hope that you will feel free to provide me with feedback on the journey. Your thoughts are always appreciated.

© 2012, David Allan Galbraith

Star Stuff? Try “Big Bang Stuff!”

One of the (deservedly) frequently quoted observations by my hero Carl Sagan is that we are all star-stuff. The chemical elements in our bodies – and everything we see around us on Planet Earth – were forged in exploding stars billions of years ago. This is a profound realization. It seems to me that doesn’t go far enough, however.

I started thinking about the origins of the elements in our bodies, and made a connection I haven’t seen elaborated before. To explain myself, I have to explain the origin of the universe first.

The 98 elements that occur in nature are divided up by astronomers into two groups: hydrogen and helium, and “metals:” all the other stuff. Hydrogen and helium were the products of the evolution of matter following the big bang. The “metals” were subsequently produced in a process dubbed nucleosynthesis: nuclear fusion taking place within stars (the process was worked out over half a century ago; the landmark paper is E. M. Burbidge, G. R. Burbidge, W. A. Fowler, F. Hoyle. 1957. Synthesis of the Elements in Stars, Rev. Mod. Phys. 29: 547). The proportions of these things are considered very important. The ration of hydrogen to helium in the observable universe is one of the hallmark tests for cosmology and models of the origins of the universe. Different models predict different ratios, and only the natural ration of about 76% hydrogen to 24% helium gets to decide which models fly.

The other stuff is used to characterize stars, with a measure called metallicity – the proportion of the stuff of the star that is not hydrogen or helium. For example, the metallicity of the sun is approximately 1.8% by weight. Put the other way, the sun is 98.2% hydrogen+helium by weight. This quantity is very helpful to astronomers as it’s a measure of the age of stars, among other things. The older the star, the higher the expected metallicity, as the metals are added by the very process of fusion. Looked at one way, it’s stellar pollution.

This started me thinking about human metallicity. There’s a nice summary on Wikipedia on the elemental composition of the human body (http://en.wikipedia.org/wiki/Composition_of_the_human_body). Here are the top ten elements and the percentage of the body, by weight and atomic proportion, that they represent:

  • Oxygen – 65% by weight but 24% by atomic proportion
  • Carbon – 18% by weight but 12% by atomic proportion
  • Hydrogen – 10% by weight but 63% by atomic proportion (!!)
  • Nitrogen – 3% by weight but 0.58% by atomic proportion
  • Calcium – 1.4% by weight but 0.24% by atomic proportion
  • Phosphorus – 0.78% by weight but 0.14% by atomic proportion
  • Potassium – 0.25% by weight but 0.033% by atomic proportion
  • Sulfur – 0.25% by weight but 0.038% by atomic proportion
  • Sodium – 0.15% by weight but 0.037% by atomic proportion
  • Chlorine – 0.15% by weight but 0.024% by atomic proportion

Ok, so what, I hear you say. Well, look at #3 in this list – hydrogen. Ten percent of our body mass is hydrogen, in chemical compounds like water, sugars, and all sorts of other things. However, two facts about hydrogen are important. First, it’s the lightest element there is, so 10% by weight is a big number by atoms. Second, hydrogen was not made by nucleosynthesis. It was made by the Big Bang itself – and sixty-three percent of the atoms in our bodies are hydrogen.

If we shift our attention away from overall proportions by mass and re-list things by number of atoms, we see a different picture of our own composition. Yes, we are star-stuff – but 63% of the atoms in our bodies have their origins in the Big Bang itself. These humble hydrogen atoms that are the majority population in our bodies – and are the most abundant stuff in the visible universe –  went through stars that exploded, but they came from the Big Bang. In a real sense, so did we.

© 2012, David Allan Galbraith

Enjoy Winter Solstice 2012!

It’s the moment of the Winter Solstice, an event that has both cultural relevance around the world and is an element of a real science (Astronomy). Read something meaningful today, like Ann Druyan and Carl Sagan’s “The Demon-Haunted World: Science as a Candle in the Dark.” (http://books.google.ca/books/about/Demon_Haunted_World.html?id=5QpLlsPPM_YC&redir_esc=y)

Today (21 December 2012) was hyped onto a cottage industry of world-wide catastrophe by a few self-interested charlatans who prayed on the gullible. It’s a very, very old story. Carl Sagan has been quoted as saying that extraordinary claims require extraordinary evidence. The whole proposition that an ancient Mayan calendar foretold that today would be the end of the world was based on less than evidence – just a misinterpretation of an ancient document. This was not the first time, or the last time, that whole industries will be built on taking ancient texts and cooling up some baloney about their inferred meaning for the future.

There is only one knowledge system that can make evidence-based predictions about the future, and that’s science. Furthermore, the method of science is dependent on putting out predictions and then testing them against nature. In science, a failed prediction just means that the hypothesis upon which it was based was falsified – it didn’t work, and we try again. In chicanery a failed prediction has no consequences, except that it’s further evidence that, as is attributed (without evidence that he said it) to P. T. Barnum, “There’s a sucker born every minute.” It’s sad. The universe is beautiful, mysterious, and rich beyond the imaginings of any of us, modern or ancient. Get to know it for itself. Look for yourself, ask questions for yourself. Get to understand. Reject what doesn’t work. And – surprise – you will be applying the scientific method yourself. It’s not about believing in anything except that the evidence you can trust is evidence that has passed the test of being put up against the touchstone of nature.

© 2012, David Allan Galbraith

Pine River Observatory is Up and Running!

I hope you enjoy your visit to Pine River Observatory. This blog will be used to post observations, photographs, and, generally, things astronomical. Over the coming weeks I will be updated and adding to the blog, including adding lots of photos and notes from months and years past.

The basic idea of Pine River Observatory is to put together a “virtual” and “mobile” observatory. Pine River, located on the west coast of Ontario south of Kincardine, is a lovely area with fairly good skies given that it’s along the shores of a major lake. Our family cottage is in the area. I can be found many summer nights with tripods, cameras, and telescopes, or sometimes just a lawn chair and binoculars, soaking up the sky.

In the future I am planning on organizing some sky watching events in the Kincardine area during the summer, or taking part in ones that might already be planned.

© 2012, David Allan Galbraith