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By Jupiter!

A blog about the stars, astronomy gifts, and other starry musings by the folks behind Indigo Night.

A favorite passage remembered

by Van Wymelenberg
August 31, 2009
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The Wind In The Willows by Kenneth Grahame has long been treasured friend, one that always delights and comforts me. My copy has the wonderful line drawings by Ernest Shepard. I won it in a book character contest one summer in my 11th year at our neighborhood library. I took top honors with my stunning and subtly nuanced interpretation of Mark Twain. As I recall I was up against quite a few Davie Crocketts and Daniel Boones, coonskin caps being all the rage that year.

I read the book every 5 years or so. The last time I read it I paid particular attention to Mr Grahame’s descriptions of the night sky. I do this with all the fiction I read now, kind of in the ‘fact-checker’ mode. (In the nautical fiction of Patrick O’Brian, especially: he has some exquisite passages about sailing at night under a vast cathedral of stars.)

In Chapter Seven of Wind In The Willows, The Piper At The Gates Of Dawn, Rat and Mole assist their friend Otter in looking for Otter’s son, Portly, who had gone missing, but not to panic or worry, Portly was always straying off and getting lost… except this time was a bit more serious, he had been missing for several days in the Wild Wood. Rat and Mole decided to continue the daytime search through the coming night, concentrating along the river.

Though it was past ten o’clock at night, the sky still clung to and retained some lingering skirts of light from the departed day; and the sullen heats of the torrid afternoon broke up and rolled away at the dispersing touch of the cool fingers of the short midsummer night.

Knowing that the Wild Wood is based, approximately, on the the area surrounding village of Lerryn, in Cornwall. And that Midsummer is the generally the time around the solstice; and (from a later conversation in which Rat mentions the fact) that moonrise was near midnight that night…

I look through the ephemeris for 50° 23’ N and 4° 37’ W on 21 June of various years, searching for a moonrise at midnight. On 20 June, 1900 I found a last quarter moon rising at 11:56 PM. That would work. 20 June of 1903 shows a waning crescent, about 32% illuminated, rising about 1:09 AM. That fits too. There was no Summer Time (or Daylight Savings Time as we say here in the states) when Mr Grahame was writing this book — that didn’t come into effect for another 10 years of so. The book was published in 1908, so I figure this was about the right time frame.

Mr Grahame describes nautical twilight – a time when horizon features are still faintly visible, but the darkening sky will offer up a few bright stars if you know where to look; and some lightness west, perhaps some high whispy clouds lit by the sun, now below the horizon. When Grahame describes his lingering skirts of light perhaps he was referring to noctilucent clouds: a high altitude cloud that is luminous at twilight at higher latitudes, such as Cornwall, near 50° North. (I’ll post on NLCs soon – uncommonly beautiful.) Nautical twilight occurs, technically, when the center of the sun is 12° below the horizon. This is when navigators locked their legs about the lower shrouds, took sextant and chronometer in hand, and determined the altitude of a particular star above the horizon. In order to plot a ship’s position.

So the first general description of night holds true: the sun was about 10.5° below the horizon at 10 PM local time, at Midsummer, in the Wild Wood, by my calculations. The last vestige of twilight would be showing west. And about the rising moon, east, toward midnight:

The line of the horizon was clear and hard against the sky, and in one particular quarter it showed black against a silvery climbing phosphorescence that grew and grew. At last, over the rim of the waiting earth the moon lifted with slow majesty till it swung clear of the horizon and rode off, free of moorings; and once more they began to see surfaces—meadows widespread, and quiet gardens, and the river itself from bank to bank, all softly disclosed, and washed clean of mystery and terror, all radiant again as by day, but with a difference that was tremendous.

I love that moonrise. I see it. It’s so true how the world is ‘softly disclosed’ by moonlight, even the light of a waning crescent moon. That is actually enough light to read by. I’ve done it.

The story continues with Rat and Mole working upstream slowly until sometime near morning twilight. He relates that

… the moon, serene and detached in a cloudless sky, did what she could, though so far off, to help them in their quest; till her hour came and she sank earthwards reluctantly, and left them, and mystery once more held field and river.

He doesn’t say the moon set but that it sank earthward reluctantly, and left them.

I believe Rat and Mole may have been on the south shore of the river, up against a tall stand of English Oak, because this type of moon would not set until well after daylight. But it could have disappeared behind the trees, certainly. (And reluctantly.)

The waning crescent moon, the moon that rises in the east at midnight, would not transit, or cross, the south meridian until the following morning, and would not set until early afternoon. Technically it is rising until it transits. Even at dawn the moon would not be sinking earthward. Except near Toad Hall. I’ll tell you though, in my experience as a walker in the woods at night, it’s all a trick of perspective. You walk down a path and the moon is well above the horizon. You work your way up a small rise, around a bend, and it’s back at the horizon, bigger, brighter, a different moon altogether. Clearly in the Wild Wood, the perspective is perfectly realized in service of a story well told. I’m sure that’s just the way it was that night.

Rat and Mole did eventually find Portly,by the way, with the help of Pan, the Piper At The Gates Of Dawn.

The Sky Tonight — Week of August 23

by Van Wymelenberg
August 20, 2009
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The moon was new on the 20th so this week we’ll begin to see the barely visible waxing crescent moon low in the west after sundown. On Sunday, the 23rd, look for the crescent moon, about 17% illuminated, and the bright star Spica, lucida (brightest star in a given constellation) of Virgo. Look toward the horizon, and a little west and you may see Saturn, and possibly Mercury, especially if you are viewing with binoculars.

After moonset, in the deepening twilight, brilliant Jupiter will show rising southeast in faint Capricornus. At the meridian, majestic Scorpius, the celestial Scorpion. Each day this week the moon rises later, and of course sets later, and more of the illuminated portion of the disk is revealed. First quarter is on the 26th. By Thursday, the 27th, the moon with be in Scorpius. Antares, the bright heart of Scorpius – a ruddy colored star, often mistaken for Mars – will show close, just to the right of the moon, now in it’s gibbous phase (gibbous: more than half illuminated, still waxing toward full.)

Next week the moon has a close encounter with Jupiter.

I love looking at the moon. Most star-gazers disdain the inconstant moon… yes, of course, it’s light steals the beauty of the night sky, of the indigo night, quoting the poem that gave us a name. But it’s just so beautiful. We forget. When I take the time to really look at the moon I still get that childish delight and amazement, that quickening, especially when I see the rise or set against a landscape or seascape. A brief meditation, and the flat disk, pie plate in the sky moon emerges as a sphere, it’s beautiful roundness an affirmation in satellite of our own world.

This is especially true with Earthshine. This is when the dark portion of a thin crescent moon is dimly lit by light reflected from earth — primarily clouds. This happens mostly when the moon is new, or near new, and stands between the earth and the sun. Here, the full face of the earth reflects light onto the moon – much more so than if the moon is off to the side or opposite the sun, at first quarter, full and or last quarter. All this reflected light falls on the dark side of the moon, filling the inky black shadow with soft light, a low level luminous haze. Texture emerges. The dark outer edge gains in definition, and it’s easier to see the moon as a sphere. The reflected light adds to the direct light that falls on the crescent arc as well, and in photographs you’ll see this as a beautiful radiant glow, just off the scale.

Earthshine, or the new moon in the old moon’s arms usually visible in twilight when the moon is in it’s crescent phase.

[This photograph is by Ilmari Karoned. It was taken in Helsinki on 21 July 2006. Used with permission under a Creative Commons license]. And I’ll leave you with this, for no particular reason: They dined on mince, and slices of quince, which they ate with a runcible spoon; and hand in hand, on the edge of the sand, they danced by the light of the moon, the moon, they danced by the light of the moon. E Lear.

FAQ 5 — Will there be a moon in my print?

by Van Wymelenberg
August 20, 2009
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It seems like an easy question, and the short answer is this: probably yes. As the moon orbits the earth it moves from new to full over the course of about 14.4 days (waxing towards full, each night it gets fuller, moving from slender crescent to bright gibbous to full) and then from full back to new (waning towards new, each night, rising about 45 minutes later, the brilliant full moon slips back to its slender crescent arc, and then again to new).

On the day of a new moon, once a month when the moon rises and sets with the sun, and perhaps for a day on either side, the print will not show a moon — it’s simply not visible in the sky at any time.
Prints produced for days when the moon is just past new, through about last quarter, will show the evening sky with the moon. Prints from last quarter through new will show the sky just before dawn, as the crescent moon sets in the west.

You can use the U.S. Naval Observatory’s moon-phase calculator to see what the moon was doing on any given date. The interface is bare-bones simple. Just key in a date and location (anything close will do for our purposes, for example any large city within a few hundred miles of the location of your event) and it will return a small chart with moonrise, transit, and set, with the phase and illumination. Any illumination above about 3% will show in the print. This will give you a chance to finesse your headline message too, when you fold the time of day into the mix.

This shows us that on this particular day the moon rose a little after 10PM and was 81% illuminated. The view in this graphic would probably be southeast around midnight, with the moon well above the horizon.

And you’re welcome to give us a call if that seems like too much work. We’ll run a quick calculation and let you know what was going on in the night sky for any given date, at any named place. 866-565-4500

And then there is this resource, at Neave.com This is a flash planetarium that returns a graphic view of the night sky when you key in a date and place. The view returned, unlike most internet night sky applications, is an elegant and informative rendering. A bit tricky to navigate at first, perhaps a touch slow, but way, way cool. Neave has some other brilliant flash apps at his site. It’s the best.

Moon Occults the Pleiades August 14

by Van Wymelenberg
August 14, 2009
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Astronomers use the word ‘occult’ to describe an event where one (larger) astronomical body passes in front of another, smaller body, momentarily blocking the view of the smaller object by observers on a third body (that would be us, on the home planet, earth). This Friday morning the waning crescent moon will occult, or pass in front of, the Pleiades. Eclipse is another word one could use, but I believe an eclipse, strictly speaking, is about the shadow it casts (upon earth, for example) rather than just blocking the view. But you’ll hear both terms used. (Occult from the Latin word occultus, “hidden.”)

Gabriella Possum Nungurrayi / Seven Sisters Dreaming

What is it about the Pleiades? An open star cluster in Taurus. A child’s box of precious jewels. Known and celebrated across so many cultures, distant and ancient, and there she is, in our own night sky, especially those clear, dark winter nights, a kind of spiritual time machine. It was common among the indigenous peoples of the Americas to measure keenness of vision by the number of stars the viewer could see in the Pleiades. I think about that.

The image above shows the seven sisters, the Pleiades, and is from a creation story that belongs to Gabriella Possum Nungurrayi, a contemporary artist living and working in the Western Desert of Australia. (The Kluge-Rhue aboriginal art museum is here in Charlottesville, by the way, and probably holds the most important and complete aboriginal art collection in the world, outside of Australia, but this piece is not part of their collection.) In her dreaming the seven Napaltjarri sisters were chased by a Tjakamarra man. Quoting with from the gallery that represents the artist:

This painting depicts the ancient myth of the Milky Way and the Seven Sisters (Pleiades). This dreaming was inherited by Gabriella from her mother and grandmother and given to Gabriella.

This story takes place at “twenty mile” located near Napperby Creek in the Northern Territory. The Seven Sisters traveled over a vast expanse of country, until they realized that they were being followed by a man called Wati-Nyiru (who was a Tjakamarra man). He was a evil person who wanted to seduce the sisters and have ownership of them, and so the women were frightened of him. They tried to hide from the man in caves, however he began disguising himself as many different things to deceive them. With little hope of relief from the man, the seven sisters escaped through a fire at Kurlunyalimpa to the Milky Way where they became the stars of the Plaeiadies in the Constellation Taurus. There they are safe, and at rest and watch out over all the women on earth. Wati-Nyiru followed them to the heavens, and become the star Orion, unable to get near them as they move across the night sky. Gabriella depicts the cloud formations in front of the Milky Way in the night sky. The seven concentric circles represent the seven sisters while the lone star represents Orion (the Tjakamarra man) which can be seen on the extreme left of this painting shown with concentric circles.

Look for the moon early on Friday, about 4 AM to see the occultation. This is a good primer on observing occultations, at Sky&Telescope

And then there’s this: Subaru is Pleiades in Japanese. Wouldn’t you rather drive around with seven sisters than, say, or a ringed gas giant?

Bellatrix

by Van Wymelenberg
August 14, 2009
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And then there’s Bellatrix one of the four bright corner stars of Orion, with Betelgeuse, Rigel and Saiph. Bellatrix, the Female Warrior. The Amazon Star. Bellatrix, riding on the shoulders of the giant, majestic Orion. Bellatrix, the 27th brightest star in the night sky. Bella, Italian, of course, for beauty; tri, for trimaran, and X just because. And then there is the whole “Trix” suffix thing to consider. Trix are for kids. Bellatrix, a serious contender.

Orion will soon come into view in the pre-dawn sky, and is easily seen if you have a clear view of the east horizon. Bellatrix will appear first — some of the ancient astronomers, Ulugh-Beg and al-Sufi, have named her al-Murzim and al-Razam, respectively, and this translates, roughly, as ‘One Who Roars.’ Some believe this is a reference to the lion skin that Orion has draped across his arm. Others speculate that the ‘roar’ is an announcement of the rising of the more brilliant Rigel, or indeed, of Orion. 3 July

from Bayer’s Uranometria. 1603

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Just Because

The night sky print which arrives for no particular reason, other than to celebrate the gift of love that is your beloved, is cherished like no other.

Birthdays

Each of us has a story that begins in a single moment. Poets and philosophers from Shakespeare to Tennyson, from Moore to Jung, share a common fascination with the night sky at the moment of birth, and the idea that the moon and stars stand in timeless, silent witness to this moment.

Wedding Anniversaries

The night sky print, showing the moon and stars just as they appeared on the night you met, the moment of your first kiss, or your wedding night, is an exceptional anniversary gift. Appropriate for any year, especially so for the 1st anniversary, the year of the ‘paper’ gift.

New Baby

The night sky print, showing the moon and stars just as they appeared on the child’s first starry night, with your words – funny, wise, sweet, hopeful, perhaps a favorite quote from a story or song – makes a beautiful keepsake.

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