Archive for the ‘astronomy’ category

Eclipses Make People Crazy, Daniel Defoe Edition

August 6, 2017

So:  some folks choked on Annie Dillard’s perhaps overly magniloquent response to her eclipse, so here’s something quite different for the more Augustan among us.

For reasons not relevant to this post, I am this morning nosing around Daniel Defoe’s writing from the late 1710s, and just a few minutes ago I stumbled upon this hoot of a passage from the second volume of The Family Instructor:

It happen’d once, that a Discourse began between the Father and Mother about the Eclipse of the Sun, which fell out in April 22. 1715.

The Eclipse of the Sun was the Subject of all Con|versation at that time, having been, as is well known, so Total, and the Darkness so great, as that the like had not been known in that Age, or some hundreds of Years before.

The Wife had enquired of her Husband, what the Nature of the Thing was, and he was describing it to her and the Children in a familiar way; and, as I said, that a kind of Reflection upon one another was the usual Issue of their common Discourse, so it was there; the Husband tells her, that the Moon was like a cross Wife, that when she was out of Humour, could Thwart and Eclipse her Husband whenever she pleased; and that if an ill Wife stood in the Way, the brightest Husband could not shine.

She flew in a Passion at this, and being of a sharp Wit, you do well, says she, to carry your Emblem to a suitable height; I warrant, you think a Wife, like the Moon, has no Light but what she borrows from her Husband, and that we can only shine by Reflecti|on; it is necessary then you should know, she can Eclipse him when she pleases.

Ay, ay, says the Husband, but you see when she does, she darkens the whole House, she can give no Light without him.

Ʋpon this she came closer to him.
Wife.

I suppose you think you have been Eclips’d lately, we don’t see the House is the darker for it.

Husband.

That’s because of your own Darkness; I think the House has been much the darker.

Wife:

None of the Family are made sensible of it, we don’t miss your Light.

Husb.

It’s strange if they don’t, for I see no Light you give in the room of it.

Wife.

We are but as dark as we were before; for we were none of us the better for all your Hypocri|tical Shining.

Husb.

Well, I have done shining, you see; the Darkness be at your Door.

It’s evident that both meant here, his having left off Family-Worship; and it is apparent, both were come to a dreadful Extremity in their Quarrel.
Wife.

At my Door! am I the Master of the Fami|ly! don’t lay your Sins to my Charge.

Husb.

No, no; but your own I may; It is the Retrograde Motion of the Moon that causes an E|clipse.

Wife.

Where all was dark before, there can be no Eclipse.

Husb.

Your Sin is, that my Light is your Darkness.

Wife.

That won’t excuse you, if you think it a Sin; can you not do what you please without me?

My advice to the husband? Don’t throw shade when your own wit is so poorly lit.

Image: Edmund Halley, A Description of the Passage of the Shadow of the Moon over England In the Total Eclipse of the SUN on the Day of April 1715 in the morning.

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Darkness At Noon (Well, A Little After 10 a.m. From Where I’ll Be Standing)

August 5, 2017

This is a follow up to what I’ve been hearing from some folks about how they plan to take in the eclipse of 2017.  My family’s headed out for Oregon in a couple of weeks, basing ourselves with relatives in Portland before heading a little south and east in the very wee hours of the 21st.

We’re putting ourselves in the hands of the cloud-cover forecast as to how far east we go (or try to), and in those of our cousins for local knowledge of roads and routes. There Will Be Traffic, which is why my hunch is that we’ll be en route not much after midnight.

That’s my plan.  What follows is for those of you in or near the path of the partial eclipse, and plan to stay there.

I’ve got just one thing to say to y’all:

Reconsider.

A total eclipse is a completely different beast from a partial one.  Partial eclipses are weird and cool.

Something comes along and takes a bite out of the soon, and the sheer wrongness of that is emotionally powerful, and produces its own truly odd visual effects:

 

BUT…

Totality is a completely different beast.

Here’s Annie Dillard, testifying:

I had seen a partial eclipse in 1970. A partial eclipse is very interesting. It bears almost no relation to a total eclipse. Seeing a partial eclipse bears the same relation to seeing a total eclipse as kissing a man does to marrying him, or as flying in an airplane does to falling out of an airplane. Although the one experience precedes the other, it in no way prepares you for it….

The sky’s blue was deepening, but there was no darkness. The sun was a wide crescent, like a segment of tangerine. The wind freshened and blew steadily over the hill. The eastern hill across the highway grew dusky and sharp. The towns and orchards in the valley to the south were dissolving into the blue light. Only the thin river held a trickle of sun.

Now the sky to the west deepened to indigo, a color never seen. A dark sky usually loses color. This was a saturated, deep indigo, up in the air. Stuck up into that unworldly sky was the cone of Mount Adams, and the alpenglow was upon it. The alpenglow is that red light of sunset which holds out on snowy mountain tops long after the valleys and tablelands are dimmed. “Look at Mount Adams,” I said, and that was the last sane moment I remember.

I turned back to the sun. It was going. The sun was going, and the world was wrong. The grasses were wrong; they were platinum. Their every detail of stem, head, and blade shone lightless and artificially distinct as an art photographer’s platinum print. This color has never been seen on earth. The hues were metallic; their finish was matte. The hillside was a nineteenth-century tinted photograph from which the tints had faded. All the people you see in the photograph, distinct and detailed as their faces look, are now dead. The sky was navy blue. My hands were silver. All the distant hills’ grasses were finespun metal which the wind laid down. I was watching a faded color print of a movie filmed in the Middle Ages; I was standing in it, by some mistake. I was standing in a movie of hillside grasses filmed in the Middle Ages. I missed my own century, the people I knew, and the real light of day…

From all the hills came screams. A piece of sky beside the crescent sun was detaching. It was a loosened circle of evening sky, suddenly lighted from the back. It was an abrupt black body out of nowhere; it was a flat disk; it was almost over the sun. That is when there were screams. At once this disk of sky slid over the sun like a lid. The sky snapped over the sun like a lens cover. The hatch in the brain slammed. Abruptly it was dark night, on the land and in the sky. In the night sky was a tiny ring of light. The hole where the sun belongs is very small. A thin ring of light marked its place. There was no sound. The eyes dried, the arteries drained, the lungs hushed. There was no world. We were the world’s dead people rotating and orbiting around and around, embedded in the planet’s crust, while the earth rolled down. Our minds were light-years distant, forgetful of almost everything. Only an extraordinary act of will could recall to us our former, living selves and our contexts in matter and time. We had, it seems, loved the planet and loved our lives, but could no longer remember the way of them. We got the light wrong. In the sky was something that should not be there. In the black sky was a ring of light. It was a thin ring, an old, thin silver wedding band, an old, worn ring. It was an old wedding band in the sky, or a morsel of bone. There were stars. It was all over.

      — Annie Dillard, “Total Eclipse”, from Teaching a Stone to Talk

My own experience was similarly uncanny, impossible to anticipate.  The first film that was really mine, the first on which I had sole producer and writer credit, was an episode of NOVA broadcast in 1992 called “Eclipse of the Century.”  It documented the 1991 eclipse whose a path of totality tracked directly over the Big Island of Hawaii — and hence over the deep-space telescopes placed atop Mauna Kea.

It was a hell of a first film to attempt — we ended up with a crew of over 20, 12 cameras, insurance from Lloyds of London against the possibility that clouds would doom the film — something like $5,000 against $250,000 on four minutes or so of clear skies — and so on.

I had a ton of help, of course:  a supervising producer, a proper director, a great assistant, and above all, wonderful camera people and their crews, in many ways a who’s-who of the top documentary shooters of the day.  Without them the whole farrago would have collapsed in hideous ignominy.

As it turned out, nature gave us great drama — clouds rising, threatening to cover the sun minutes before totality and then…

Well, take a look at this clip.*

For myself — I was with the crew that was filming the adventures within the control room of the Canada-France-Hawaii Telescope.  That was headed by Jon Else, for those of you who follow documentary stuff, and though I was nominally his director, Jon needed no guidance from a rookie to do his usual brilliant work. About 90 seconds into totality he turned his head and told me to get onto the catwalk to see the matter for myself.

I did.

I’m not going to tell you what I felt.  As the Dillard passage above suggest, it seems to me, words can carry something of the emotional intensity of the moment, but the experience itself is unsayable.  Mimesis ain’t in it here; there’s no representation that captures the reality anyone other than the writer would perceive.

In purely descriptive terms, the shift in colors that Dillard describes is the overture, the phenomenon that alerts you to the strangeness under way.  But when the moon’s disc fully covers the sun you get something else altogether, a darkness that isn’t quite the darkness of night (especially if you’re high up, with a truly distant horizon, because you can then detect a kind of lightening all around you at the edges of your viewable frame).

And most of all, you get the corona, the solar atmosphere. The human eye can see it out to a distance of at least 10 solar diameters, maybe more.  But because the brightness falls off so sharply from near the limb of the sun to hte diffuse, outer corona, most  most photographs, and certainly in the video linked above, don’t begin to do justice to what you’ll see for yourselves.

Luc Viatour / https://Lucnix.be

All of which is (a) to prove the point that words are poor guides to what happens during totality and (b) if you have a chance, check it out.

*I can’t find the whole film on the web anywhere.  That’s no surprise — in 1992 we weren’t clearing rights for an internet that wouldn’t properly exist for years to come.  One cool thing about that eclipse that you’ll see if you do look at the clip were those two giant solar prominences.  Don’t see that every time.

Images: George Stubbs, Eclipse at Newmarket with Groombefore 1789.

Photos of a partial eclipse of the sun taken in Yunnan province, China, 1999

Luc Viatour, Total Solar Eclipse, 1999

Lunacy

November 12, 2016

I’ve got some brewing thoughts about what comes next, in line with and in some cases following on from what others, made of stronger stuff and able to drag words out rage and despair more quickly than I, have already written.

But we do not live by politics alone, however much we may have to over the next months and years. So here’s advance warning of a little bit of wonder, ours for the having:

But this month’s Supermoon is special. The eccentricity above is calculated based upon the Earth-Moon system, but other celestial bodies also influence the Moon’s orbit through gravity. The Sun plays the largest role, but so too does Jupiter and even some of the smaller planets. When factoring in these other influences, the eccentricity of the Moon’s orbit can actually vary by as little as 0.026 and as much as 0.077.

A more eccentric lunar orbit brings the perigee [its closest approach] nearer the Earth, and when this perigee occurs during a full Moon, we get an extra-Supermoon. That is what will happen on Nov. 14, when the Moon will come to within just 356,509km of Earth, which is the Moon’s closest approach since Jan. 26, 1948. The Solar System won’t line up this well again for a lunar approach until Nov. 25, 2034.

joseph_wright_of_derby_-_a_view_of_vesuvius_from_posillipo_naples_-_google_art_project

That sucker is going to be big, really big –a “normal” Supermoon is 14 % larger and 30% brighter than a full moon at apogee — the point on an elliptical orbit farthest away the focal body.  It’s actually hard to perceive the effect as a casual observer, but it is naked-eye detectable.  The absolute peak of the phenomenon comes at 8:25 a.m. ET this coming Monday, but if you’re up early and/or catch the rising moon Monday evening, you’ll get a fine approximation.  As they say:  check local listings.

One of the consolations/delights I take from nature is the sense of connection to something larger than myself. That’s the same feeling I get from the acts we take to make the world better, from the kindness we show to one person at a time to the actions we’re stumbling to figure out right now, here on this blog and at every turn.

I’m going to stare at that moon Monday (sky permitting) and think of the world I want the next time this particular geometry rolls around, twenty eight years from now.  My son will be thirty four then.  If I’m fortunate enough to be here with him, I’ll be seventy six.  It will be a better world then, if we make it so.

And if it makes me a lunatic to think so, I’ll take that label gladly. Beats the alternative.

Image: Joseph Wright of Derby, A view of Vesuvius from Posillipo, Naplesbetween 1788 and 1790.

For a Good Time In Radioland (Short Notice Self Aggrandizement)

October 6, 2016

ETA: So, we lost the connection to Blog Talk radio.  Jay and I continued the conversation to tape; he’s editing it now and will post the audio as a podcast tomorrow.  I’ll let y’all know when it’s up.  Sorry…

dou_astronomer-by-candlelight

Don’t know if anyone reading this has had their fill of The Hunt For Vulcan, but just in case you haven’t, I’ll be talking soon about that book, missing planets, error in science (and life, perhaps) and more with Jay Ackroyd on his internet radio program, Virtually Speaking.

Time: 9 p.m. Eastern, 6 Pacific (one hour from now!)

Here’s the link.

Tune in, if you’re not absorbed in more down-to-earth matters. (I.e….Go Sox!)

Image:  Gerrit Dou, Astronomer by candlelight1665

Brave New Worlds

May 2, 2016

You may have caught this news, but today Nature published a report on the discovery of three earth-scale planets in orbit around just about the least impressive star it’s possible to be.

Edvard_Munch_-_Starry_Night_(1922–24)

What’s most intriguing is that the dimness of that parent star — now known as TRAPPIST-1, after the instrument at the heart of this discovery — makes it just possible (if you squint just right) to glimpse a possible opening for life on its planets.

It’s tricky, because the two better-characterized planets are terribly close to their sun, with orbits of 1.5 and 2.4 days.  But TRAPPIST-1 is what’s called an “ultracool dwarf” — and even at that distances, the two planets would have equilibrium temperatures that are pretty damn hot.  But — if everything broke just right, there would be some locations that could be cool enough to support liquid water on the surface.

That’s one of the big pre-conditions exobiology researchers/dreamers imagine would be valuable/necessary for the emergence of life beyond earth.  Given how many ways we can imagine (and all the ways we can’t) that those circumstances might not pan out, I wouldn’t hold my breath waiting for a signal from our new friends on a distant world.

But the real juice behind this finding comes from the fact that these planets are decent candidates for transmission spectroscopic analysis of their atmospheres (if they have them) during their transits across the face of their star.  All it will take is the next generation of large, infrared-capable telescopes:  the James Webb Space Telescope, scheduled to launch in 2018, and instruments like the Giant Magellan Telescope, the European Extremely Large Telescope, both now starting construction in Chile, and the Thirty-Meter-Telescope, now stalled in Hawaii.

I write more about this over at The Atlantic. It’s a fun tale — a small team pursuing a hunch that has led to a significant (or at least enticing and delicious) advance in our grasp of the possible out there.

So — if you’re tired of terrestrial politics, have some fun contemplating possible home worlds for the Lectroid going by the name of Cruz.

Image:  Edvard Munch, Starry Night, 1922-24

A Big Effing Einstein Deal

February 11, 2016

Just a quick note here as I’m on deadline for a piece on this stuff, but today we got the official announcement of the worst kept recent secret in physics.  Here, via the Guardian, is the TL:DR version of what was said:

On 14 September 2015 at 9:50 GMT, the two detectors of the newly upgraded Laser Interferometer Gravitational Wave Observatory (LIGO) detected a signal.

It was unambiguously a gravitational wave signal because it matched the predictions from Einstein’s general theory of relativity almost precisely.

J.M.W._Turner,_R.A._(1775-1851),_Storm_at_Sea.Christie's

This is huge news, as it is, among other things, the latest and most elusive (so far) direct confirmation of Einstein’s General Theory of Relativity, a theory of gravity that describes what we feel as a force holding our feet to the floor is in fact the local warping of spacetime by matterenergy. (In the case of our feet and our floor — that warping is the dent in spacetime created by the mass of the earth.)

It is as well a triumph of virtuosity in observation and measurement.  The detection of a gravity wave is a simply wondrous an act of human hands and mind.  It is a joy to witness, at least for me.

More after I get the paying work done….

Image:  J. W. M. Turner Storm at Sea 1851 or before.

Programming Note/Self Aggrandizement — Vulcan/Planet Nine Edition

January 29, 2016

Hey, all:  if you’ve got a moment this afternoon, I’ll be talking with Ira Flatow on Science Friday about The Hunt for Vulcan in the context of last week’s announcement about Planet Nine.

Radio_King_poster

I’ll be on in the second hour, starting at around 3:20 ET, maybe a couple of ticks before, and rabbiting on with Ira until about 3:38.  Some NPR stations fecklessly omit the second hour of Science Friday, so check local listings.  You can always catch it live or later at the Science Friday site.

While there may be better ways to spend 18 minutes of your life…there are surely worse ones too.  Come on down if you’ve time and the inclination.

Image: Poster for the film, The Radio King, 1922.