Saturday, December 9, 2017

Flat Earth "Theory?" (1 of 2)

"...the first-ever Flat Earth International Conference drew about 800 people from across — not around — the world to Raleigh, N.C."  (Boston Globe, 11/20/17)

Recent news coverage of modern flat-earthers, noticed in NBA players, a popular rapper, and most recently in a gentle probing of a New England man by the Boston Globe, reminded me of my long-ago days teaching seventh-grade earth science. 


I had heard something of the Flat Earth Society, and its members' insistence that they were not moved by "hearsay evidence" such as the testimony of astronauts, or photos or videos from space (which could be faked).  This seemed to me a laudable spirit, and in one class project I tried to inculcate a little healthy skepticism into students who were accustomed to believing whatever they were told.  (I frequently fielded questions about UFOs from students who had seen a "special" on TV, for example, and also conducted nifty class experiments to debunk astrology.)  Acknowledging that direct evidence was more trustworthy, we therefore worked through a few simple observations available to earth-bound observers, culminating with students writing letters to the Society's then-president Charles K. Johnson, pretty much proving that the earth  is, indeed, round.  

My class focused on observations that did not require trust in others, nor expensive travel.  Students wrote that sailors have, for centuries, judged the distance to another ship by how much is visible above the curve of the ocean's surface with such terms as "hull down" and "topsails down."  They pointed out that in a lunar eclipse, the earth's shadow on the moon is always curved.  Comparison of airline flight routes with a flat earth map would reveal that international flights typically follow "great circle" routes that are only possible on a curved earth.  The stars visible in the night sky not only change though the seasons, but are also different in different latitudes*--which could only occur on a round earth.  (That bends the rule about limiting travel expenses.)  Delighted to discover that Johnson had married an Australian, we urged him to telephone his in-laws and hear that they were experiencing the opposite time of day. 

Neill DeGrasse Tyson posted a similar image, with a caption something like, 'eclipse the like of which no flat-earther has seen, ever.'  (Photo from Oddstuffmagazine.com)

Flat earthers have answers (of a sort) for some of these.  A lunar eclipse is the shadow not of the earth, but of a small, round object orbiting the sun too closely to be visible.  (I suppose it's just a coincidence that the movements of this object coincide perfectly with those of the earth.)**  The apparent sinking of a ship as it nears the horizon is (somehow) the result of perspective.
Unfortunately, we never heard back from Mr. Johnson; I learned a little later that the organization was moribund even then, and Johnson himself fell on hard times, and died a few years after our letter-writing ended.

The curvature of the earth is, in fact, directly observable in some circumstances.  A hero of mine, Darwin friend and natural selection co-discoverer Alfred Russel Wallace took on a flat-earther in his own day.  The field of battle was a British canal that ran straight and true for six miles--adequate for detection of curvature under the right circumstances.  Wallace mounted marks on convenient bridges at fixed heights above the water and found that these marks did not line up visually, showing that the surface of the canal was curved.  (In so doing, Wallace won a wager, but the loser began a campaign of slander and filed a expensive law suit, and Wallace was never able to collect.)  The Bedford Canal is again a battle-ground, with newer flat-earthers declaring that the canal is, actually, flat.

When you look at the image above, other inconsistencies will occur to you!
(from flatgeocentricearth.wordpress.com)

I didn't realize when I was teaching seventh grade that most flat earthers imagined that the sun moved in a circle over a flat earth in which the north pole was in the center while the Antarctic formed the edge.  This would be to easy to disprove: the sun would move closer and farther, but never set below or rise above the horizon.  Their explanations of this simplest observation are the least convincing of a pretty unconvincing bunch: something about the sun's changing distance being exactly countered by some sort of perspective effect.  (Other explanations are simply gobbledygook.)  A non-mainstream site called The Creator's Calendar posits "Three Unanswerable Objections to the Flat Earth Theory."  It does a pretty convincing job, while treating adherents ("The Honest of Heart, as they seek for truth as for buried treasure") with sympathy and respect.

Nor did I realize that flat-earthers invoked Einstein to explain apparent gravity. They explain that, while some objects exert gravity, the earth does not; we feel instead the upward acceleration of the earth at a rate of 9.8 meters per second per second.*** (Einstein, in his theory of general relativity,  showed that acceleration could perfectly mimic gravity.)  A nifty idea, except that, from a dead stop, the earth would exceed the speed of light in less than a year!  

(Image from albertonrecord.co.na)

One of the striking things about flat eartherism is its skepticism of the entire scientific framework.  One of the key questions about any new discovery is how it fits in with established knowledge; a new discovery that requires overturning long-established frameworks warrants enormous resistance: it is much more likely that the new discovery is bogus, than that a much more-established and coherent framework is.  Believers in a flat earth must discard much more than simply recent space travel--the whole of astronomy and cosmology, universal gravitation, and even classical physics all go out the window.

That's because scientific knowledge is not a collection of disconnected facts, but a (mostly) strong framework in which major elements complement and support each other.  (One fundamental “break” in this framework has long concerned physicists: Einstein’s general theory of relativity--whose validity is very well supported by diverse evidence--does not appear to connect with quantum physics--which is also very well supported by diverse evidence.)  

But flat earth "theory" is not only inconsistent with this framework--it is also inconsistent with itself.  Objects have gravity (which explains their orbits), but the earth does not.  The sun and moon have gravity, but move in circles over the surface of the earth in a way gravity could not explain.  Acceleration mimics gravity for the earth in accordance with Einstein, but Einstein shows that no physical object can reach the speed of light (and even approaching that speed is very difficult).  The sun and moon either approach and recede without changing their apparent size, OR they behave like spotlights shining first in one place and then another--but without the visual appearance such a light would show.  And so on.


Why my quotation marks on flat earth "theory?"  Common usage notwithstanding, THEORY is the highest level of scientific knowledge.  Any theory must not only be supported by a LOT of evidence, but that evidence must converge from different disciplines.  (Evolution by natural selection, for example, fits this bill very well, since it is solidly supported by fossils, the anatomy of modern species, genetics, molecular biology, and modern field research.)  Finally, the theory must be in accord with established knowledge. (On the very rare occasions they aren't in accord, a scientific revolution is in order!  Such a revolution occurred in geology when the theory of plate tectonics overturned some of the underpinnings of geological thought a half-century ago.)


Scientific theories fit all three criteria: a lot of evidence, from diverse directions, converging toward an explanation that accords well with the established framework.  Flat earth "theory" plainly fits none of them.  

Why, then, do some people take it seriously?

*I remember seeing the Southern Cross (never visible from nearly all the continental US), as well as the Large and Small Magellanic Clouds (really only clear from the southern hemisphere) when I was a Peace Corps Volunteer in Samoa many years ago.  But you don't need to travel at all: as the stars appear to move with the rotation of the earth, they do not "recede" out of our sight as they would if they hovered low over a flat earth--otherwise the constellations would appear to shrink; another simple disproof of a flat earth.

**If that isn't enough, orbiting objects move faster--not slower--the nearer they are to their "primary," so the earth could not possibly keep pace with a small object orbiting nearer the sun.

***propelled by dark energy, no less!

Saturday, November 4, 2017

Nippenicket November


Consumed by planning my abortive attempt at the Wampanoag Canoe Passage, I actually only kayaked a few times this season.  Today I woke to a bright, cool morning and determined to go to my favorite pond for the first time this year.  My only plan was to enjoy whatever fall color remained.  

Bridgewater's Nippenicket pond is a mile long with a crinkly shoreline and a few small islands.  Waterfront houses both modest and palatial dot the southern shoreline, displaying the variety of ways people enjoy the water.  I have habitually wandered these shallows in my kayak and shamelessly gazed into people's backyards.  Today, though, I went another way, along the straighter eastern shore and soon reached the northern half, which snugs into the edge of the fabled Hockomock Swamp.  I hadn't been this way in over a year, and had forgotten how pretty these wilder parts are.


 I would have LOVED to have a treehouse like this overhanging the water.  Heck, I'd still love it.


 At this point, the road comes close enough to the pond to leave no room for a house lot.
I like to imagine neighborhood kids take advantage of this "unusable" waterfront.


 Little fall color remains.  Here is, I think, highbush blueberry (above) and black oak (below).






I think this is the last house but one before the Swamp.  Quite an estate; a bit out of my price range.
I'm betting nice views from the giant windows and lower and upper decks.

 Birch glows in the sun.



A kitchen stool, in good condition, upright, in the middle of nowhere.  (This photo
beside entry for "middle of nowhere" in the dictionary.)  Evidence for the recent
operation nearby of an Infinite Improbability Drive?  Probably not.  But still...


Nearing the northern end.

Ponds generally get shallower and smaller over time.  This was likely
once an island in the larger pond.  Now it is an island in the marsh.  



 It's hard to see here, but a track through the marsh continuing into a path ashore
tells of regular visitors to this island.

I wish I'd realized where I was when I took the videos below.  I was near the northernmost part of the pond--a place usually choked with water plants and nearly impassable, but accessible at the high water level after all the rain we've had.  The pond is there the source of a stream that flows into the Swamp, and eventually becomes a major tributary of the Taunton River.  In years past I despaired of ever reaching that stream, but it would have been much easier today.  I think I see a return trip this season.





Headed home.


Friday, November 3, 2017

Blue Hills Reservation: Natural Gem of the Boston Area (7) Indian Pass Path and Crags Foot Path

Preamble  On the way to my intended hike late in September, I stopped at Chickatawbut Overlook, where a patch of low ground is cut over at intervals to maintain a meadow that gives a view of Boston.  I like meadows, and wasted little time in getting down into it.

Chickatawbut Overlook, and the view from the wall at the top of the meadow on a hazy day.

The meadow, and a steeplebush (Spirea tomentosa) I collected seeds from: I want to grow some.

Back of the overlook is a fairly civilized and well-traveled walk up Chickatawbut Hill.


Views from the top of Chickatawbut Hill.


The main event   The northeastern end of Blue Hills Reservation stretches beyond the Blue Hill Reservoir and Chickatawbut Road into Quincy.  I parked in the small lot just west of the reservoir, and crossed the street and headed into the woods on Brook Path.


I planned to take a connecting path from Brook Path to Fox Hill Path
and thence to Indian Camp Path--until I saw how steep it was.
Going farther brought me to another connector without the need to scramble.


Higher and drier ground made for more open woodland.

Silverrod (Solidago bicolor) growing amongst grasses and chestnut oak (Quercus prinus) seedlings.


A little fall color in huckleberry (Gaylussacia) and a lowbush blueberry (Vaccinium pallidum).


Panicled hawkweed (Hieracium paniculatum).

A rare sign marks this as a green dot trail--a forest track.


I think these distinctive little dingles or hollows--perhaps six fee
deep at the deep end--are natural, but I have no idea how they form.

Perhaps the largest chestnut oak I've seen.

Yellow birch (Betula allegheniensis).

Sassafras.

The only water I saw on the walk.

I've seen a lot of fallen trees, but none with a root spread so big!  It still had some dead leaves,
but the stones unearthed by its fall were clean, so the tree probably fell months ago.

Red maple (Acer rubrum.)


The returning connector from Crags Foot Path joins a gas pipeline route for a distance.

The sunny pipeline route was perfumed by sweetfern (Comptonia peregrine)--a relative of bayberry.

Goldenrod and aster on the pipeline.

Yellow birch.

Spicebush (Lindera benzoin) is a shrub I associate with rich woods.

Rattlesnake plantain (Goodyera pubescens), with its variegated leaves,
is an easy-to-recognize native orchid.


Gently up, then steeply down Fox Hill.
The slope looks a little less forbidding than it did from the bottom, at the start of the walk.

This brings to an end my forays into parts of Blue Hills Reservation new to me.  But I have already been back to several of them--for some things bear repeating.