I had not seen Natalie Angier's article in the Science Times
The Biggest of Puzzles Brought Down to Size before wrapping up April's Moondark. Spooky ... We both must have been influenced by what I consider to one of the most empowering books I have ever read, John Harte's , Consider a Spherical Cow: A Course in Environmental Problem Solving. It's still in print!
Monday, March 30, 2009
Sunday, March 29, 2009
How Many Amateur Astronomers Are There in the US?
Here are two very rough ways to get an answer:
1. There are 300,000,000 people in the US, and maybe 1 in 100 (at most) has a telescope. Thus there are 3 million amateur astronomers in the US.
2. There are 50 states in the US, and each one has, say 4 astronomy clubs, with perhaps 150 members each. That's 30,000 amateurs.
While these numbers seem reasonable, the overall result is pretty poorly constrained. Can we do better?
Another way to estimate the number is from magazine circulation. A bit of web-searching reveals that Sky & Telescope and Astronomy magazines have circulations around 100,000, so double or triple that (since not all amateurs subscribe) to yield 300,000. By the way, that's the geometric mean of the two estimates above. Does 1 in 1000 people owning a telescope seem right to you? Is that close enough?
Probably a more pertinent question at this point is just what is a amateur astronomer? Certainly arm-chair enthusiasts count, as do those joining a club or purchasing a telescope.
How would you recognize a bona fide star-gazer if you saw one? Knowledge of the sky, solar system and constellations? Size of telescope and skill at using it under the starry sky? Total dollar investment in optics electronics and other accessories? Willingness to share what they know with those less familiar with the sky?
1. There are 300,000,000 people in the US, and maybe 1 in 100 (at most) has a telescope. Thus there are 3 million amateur astronomers in the US.
2. There are 50 states in the US, and each one has, say 4 astronomy clubs, with perhaps 150 members each. That's 30,000 amateurs.
While these numbers seem reasonable, the overall result is pretty poorly constrained. Can we do better?
Another way to estimate the number is from magazine circulation. A bit of web-searching reveals that Sky & Telescope and Astronomy magazines have circulations around 100,000, so double or triple that (since not all amateurs subscribe) to yield 300,000. By the way, that's the geometric mean of the two estimates above. Does 1 in 1000 people owning a telescope seem right to you? Is that close enough?
Probably a more pertinent question at this point is just what is a amateur astronomer? Certainly arm-chair enthusiasts count, as do those joining a club or purchasing a telescope.
How would you recognize a bona fide star-gazer if you saw one? Knowledge of the sky, solar system and constellations? Size of telescope and skill at using it under the starry sky? Total dollar investment in optics electronics and other accessories? Willingness to share what they know with those less familiar with the sky?
Sunday, February 22, 2009
Wrong Way Snowball
Comet Lulin and why it's racing the wrong way across the sky at Moondark for March. Here, a fuzzy, greenish Lulin forms the bottom vertex of a triangle with η and 10 Virginis on the morning of 21 February (composite of 10, 15-s untracked exposures with a Canon 350D).
Friday, February 13, 2009
When 13 = 1234567890
Today is Friday the 13th, the first of three this year1. It’s also 12345678902, that is the number of seconds since midnight on New Years 1970 not counting leap seconds, known as Unix time, the internal reckoning of my MacBook (date -r 1234567890) and various Ubuntu boxes. Try this:
perl -e 'print "\n",scalar localtime(1234567890),"\n\n";'
Excel counts days from the beginning of the 20th century, but Windows and Mac versions use different starting points. See for yourself by comparing PC's and Macs by typing: =DATEVALUE("1-Jan-1904"). Astronomers count Julian days from 4713 BCE, but start at noon UT on the first day of the year. Here, 1234567890 = JD 2454876.27188.
Clearly there are many ways to keep time and mark a calendar. Civilizations come and go along with their calendars: someone's, somewhere is rolling over or reaching some magic number all the time. So it is difficult to get too worked up over the Mayan calendar that will roll over in 2012, on 21 December. There is no need to worry, really there isn't.
1The others are in March and November
2Exactly so at: 6:31:30 pm EST
perl -e 'print "\n",scalar localtime(1234567890),"\n\n";'
Excel counts days from the beginning of the 20th century, but Windows and Mac versions use different starting points. See for yourself by comparing PC's and Macs by typing: =DATEVALUE("1-Jan-1904"). Astronomers count Julian days from 4713 BCE, but start at noon UT on the first day of the year. Here, 1234567890 = JD 2454876.27188.
Clearly there are many ways to keep time and mark a calendar. Civilizations come and go along with their calendars: someone's, somewhere is rolling over or reaching some magic number all the time. So it is difficult to get too worked up over the Mayan calendar that will roll over in 2012, on 21 December. There is no need to worry, really there isn't.
1The others are in March and November
2Exactly so at: 6:31:30 pm EST
Thursday, February 12, 2009
Happy 200th Birthday Charles and Abe!
Not sure I can add anything insightful to what’s already out there about these two individuals. Except my opinion that it’s pointless to try to compare them, and only a little more enlightening to ask “What would they think if they came back today?”
After all, they’re still here, their names are attached to their original accomplishments as well as to ideas, causes and controversies in the forefront today, but ones that they could have known nothing about. Darwin’s head often appears on a monkey’s body, although he didn’t discuss the evolution of man in the 1859 On the Origin of Species. Darwin’s finches put the Galapagos Islands on today’s map as the premiere eco-travel destination.
We put Lincoln’s head on the penny, a coin that scarcely anyone will bother to pick up off the ground. In a far more appropriate setting, you can read some of the grandest of his writings etched in the wall of the Lincoln Monument. In the Gettysburg Address, Lincoln spoke of unfinished work.
It’s fortunate they are still around as we’re not done with them yet, and we have work to do. Natural selection drives evolution, fossils are the evidence and molecular biology explains how it works, but only about half of Americans believe in evolution. And recent political events aside, racism is still here. It manifests itself in social and economic inequality in this country and around the globe.
So it’s a good thing to recognize Charles and Abe, I think.
After all, they’re still here, their names are attached to their original accomplishments as well as to ideas, causes and controversies in the forefront today, but ones that they could have known nothing about. Darwin’s head often appears on a monkey’s body, although he didn’t discuss the evolution of man in the 1859 On the Origin of Species. Darwin’s finches put the Galapagos Islands on today’s map as the premiere eco-travel destination.
We put Lincoln’s head on the penny, a coin that scarcely anyone will bother to pick up off the ground. In a far more appropriate setting, you can read some of the grandest of his writings etched in the wall of the Lincoln Monument. In the Gettysburg Address, Lincoln spoke of unfinished work.
It’s fortunate they are still around as we’re not done with them yet, and we have work to do. Natural selection drives evolution, fossils are the evidence and molecular biology explains how it works, but only about half of Americans believe in evolution. And recent political events aside, racism is still here. It manifests itself in social and economic inequality in this country and around the globe.
So it’s a good thing to recognize Charles and Abe, I think.
Sunday, February 8, 2009
So Long Snow Moon!
The ice on the pond has melted, the songbirds are back and the sunshine is warm! Even though we're still 20 days (and 3 hours, but who's counting) from meteorological spring on 1 March and 40 days from our astronomical vernal equinox: I'm calling it: Spring is here.At right, the tonight's full moon, enroute to a penumbral eclipse in about 12 hours, shows there's no leaves on the tree—not yet.
Monday, January 26, 2009
Happy and Prosperous Lunar New Year!
Or: 新年快乐 and 恭喜发财 (mostly just to see if I could cut and paste these characters—it works!) in the year 4707, 4706, or 4646. So many calendars, so little time ...
Sunday, January 25, 2009
One Down, Only 35 To Go ...
And that's just for the the Sandpipers!Dunlins (Calidris alpina) at Slaughter Beach, feeding on reefs of the sandbuilder worm, Sabellaria vulgaris
Saturday, January 24, 2009
Sunday, January 11, 2009
Running out Winter
Winter's settling in: leaden sky, low, filtered sun, and persistent, penetrating chill. Even so, the days are getting longer, and last night's full moon near-perigee was impressively bright for those who could see it. But it's not astronomical spring until 7:44a EDT on 20 March (11:44 UT (USNO AA Earth's Season's). We switch to daylight time on the 8th, the second Sunday in March.
In the meantime, Venus dominates the evening twilight, we miss two eclipses (an annular eclipse on the 26 Jan and a penumbral on 6 Feb), and in February, we experience the first of the year's three Friday the 13ths.
We're in a comet-dry spell, but our observing luck may be improving. This winter's big event looks to be a relatively bright comet, denoted C/2007 N3 Lulin, which may be visible to the unaided eye around its closest approach to Earth on 24 Feb, well placed for viewing in Leo. ... Watch this space and hope the weather holds!
In the meantime, Venus dominates the evening twilight, we miss two eclipses (an annular eclipse on the 26 Jan and a penumbral on 6 Feb), and in February, we experience the first of the year's three Friday the 13ths.
We're in a comet-dry spell, but our observing luck may be improving. This winter's big event looks to be a relatively bright comet, denoted C/2007 N3 Lulin, which may be visible to the unaided eye around its closest approach to Earth on 24 Feb, well placed for viewing in Leo. ... Watch this space and hope the weather holds!
Leap-Second Update
One GPS (the least expensive unit as it turn out), showed 18:59:59 for two seconds. To be continued.In any case, it's a lot more fun and far more useful to geotag photos with GPS tracks. Uncovering a workflow in OS X (a decided preference) has been a wild-goose chase, but the end is in sight. More track and photos this week.
Wednesday, December 31, 2008
"One-thousand-one ..."
One second is a breath, a heartbeat, a thought, even a relatively slow Google search. It's also what's been tacked-on to 2008, a leap second to go along with the leap day last February 29th, all to keep time in sync with our perception of the proper day. But how do you observe the leap second, capture and make the most of it? In 20th century analog mode, try digging out a short-wave radio, and tuning in at just before 7p Eastern time. A digital experience turns out to be much more complicated, with multiple time protocols and time scales, software glitches and delays. The most commonly used accurate time source is a GPS, and its internal time is actually ahead of UTC (clock time to you and me) and has no leap seconds. The closer you look the more mysterious it all is, and in truth general relativity provides relativistic incantations that allow GPS to keep time accurately if not find your way home. Einstein's time is knotted up with space and mass and "dark" things we know next to nothing about. Our time is a fairytale and much sleight of hand is needed to keep it that way.
It might be more meaningful to take that moment to reflect on one of three laws by a notable author who passed on in 2008, Arthur C. Clarke: "Any sufficiently advanced technology is indistinguishable from magic."
It might be more meaningful to take that moment to reflect on one of three laws by a notable author who passed on in 2008, Arthur C. Clarke: "Any sufficiently advanced technology is indistinguishable from magic."
Saturday, December 27, 2008
On a Lighter Note ...
At this point, we've made it well past the solstice, and the days are certainly, if not perceptibly, getting longer. The posting below and this month's Moondark (under construction at the moment) are a bit dark and too reflective. To brighten things a bit, here are some of my favs from, xkcd.com with somewhat lighter takes on of science, scale, space and time, and our place in the Universe.
Sunday, December 21, 2008
Megalithic 2.0 and the Winter Solstice
There's something disconcerting about watching a live webcast of the winter soltice sunrise from a 5000 year-old megalithic tomb at Newgrange, Ireland. While it's unlikely I'll set an early alarm, I'll probably check out the replay later in the day.
It's cool, but completely lacks context. For some perspective, see Alan Boyle's Hope on a Pale Blue Dot post at the Cosmic Log, a thoughtful reflection on Carl Sagan, which includes a 1977 video (is that lecturer the real Profesor Sagan?). Boyle saves the best for last: a mashup of Sagan readings paired with an Academy Award-like tribute compilation of film clips. All that comedy, romance, drama and conflict, joy and inhumanity indeed happen on the Pale Blue Dot, in just a portion of a pixel.
Sagan's words and set against a myriad of images of mankind, even the simple fact that we could take that image and know our true place and scale in the universe, all demonstrate to me one critical thing. This species can comprehend things bigger than anyone or anything on our home planet. Good thing too, we must now start taking care of it and treating one another the way we would want to be treated.
And that's an appropriate sentiment for the winter solstice.
P.S. Our winter begins at 0704 EST on Sunday the 21st (1204 UT)
It's cool, but completely lacks context. For some perspective, see Alan Boyle's Hope on a Pale Blue Dot post at the Cosmic Log, a thoughtful reflection on Carl Sagan, which includes a 1977 video (is that lecturer the real Profesor Sagan?). Boyle saves the best for last: a mashup of Sagan readings paired with an Academy Award-like tribute compilation of film clips. All that comedy, romance, drama and conflict, joy and inhumanity indeed happen on the Pale Blue Dot, in just a portion of a pixel.
Sagan's words and set against a myriad of images of mankind, even the simple fact that we could take that image and know our true place and scale in the universe, all demonstrate to me one critical thing. This species can comprehend things bigger than anyone or anything on our home planet. Good thing too, we must now start taking care of it and treating one another the way we would want to be treated.
And that's an appropriate sentiment for the winter solstice.
P.S. Our winter begins at 0704 EST on Sunday the 21st (1204 UT)
Tuesday, April 8, 2008
Here’s What I Need to Learn
A laundry list: Insert hyperlinks (check), construct bulleted and numbered lists (for top-ten favorites), add images (I have heaps), blog by mail, and of course, customize this blog’s layout and get it just right by tweaking the CSS. Geo-tagging my photos, and more about Google Earth and Sky View as well as the web version, GIS generally, Python, R and MySQL specifically (mostly for work). Keeping my desktops clean and active folders organized and synced.
How about: how to sort my digital photos? And take better photos (still life, nature, sky, people, high dynamic range, and close-up/macro/micro). And identifying shorebirds.
I’d better get to work. You’ll be able to check my progress here.
How about: how to sort my digital photos? And take better photos (still life, nature, sky, people, high dynamic range, and close-up/macro/micro). And identifying shorebirds.
I’d better get to work. You’ll be able to check my progress here.
Sunday, April 6, 2008
OK, Here’s Another
You teach best what you most need to learn.
--Richard Bach
Between the sentiment of this quote and the wryness of the previous one, you’ll find the boundary conditions of this blog.
Tuesday, April 1, 2008
Subscribe to:
Posts (Atom)
