Devices, 1: Star Hat

I got a phone call from New York.  Bruce King told me he had arrived from New Zealand, and had an astronomical invention that he wanted to show me.  He hoped to start a small enterprise rather as I had done.

What was his product?  He said it was a sort of portable planetarium; three-dimensional, could show the sky for any place and time, yet could be carried in the hand.  I struggled to visualize it and couldn’t, and he left it that way so that I would be the more impressed when I saw it.

He arrived in South Carolina, opened his box, which was itself a fine piece of his craftsmanship in wood, and took out his device.

It’s a ball made of – I’ll call it rubber, though it may be some other flexible material.  I still have it, and it may have become a little limp.  The ball is eight inches in diameter, like the Sun in my Thousand-Yard Model of the Solar System.  On it are printed the stars and constellation form-lines.  But the ball looks like only half a ball, because inside it is a metal ring, a hoop.  By pushing one half inward, so that the hoop forms a rim, the sphere has been converted to a hemisphere.

That’s the way it came, and I don’t think I could pull the pushed-in half back out (it only begins to come, with reluctance and a warning squelchy sound), because there’s no air inside.  You can see a seam, around the celestial equator, where the two halves of the sphere were joined after the hoop was inserted, and a sealed hole at the north pole where the air was extracted.

So what is shown in the concave half is a celestial hemisphere, seen the right way around, with the stars in the right relative positions.  This is different from an ordinary celestial globe of transparent material, which rests on a stand and has the star map inverted on the outside, so that you have to peer through the nearer side toward the farther in order to see the constellations the right way.  Older non-transparent celestial globes, such as the ancient Farnese one, had to have the constellations drawn on the outside, as on the outer view of the flexible globe, and then the problem was whether to draw them  in their right relations as seen from Earth in the center – which would make their shapes reversed as seen from outside.

The edge made by the internal hoop is the horizon.  And the key quality is that, since the globe is made of pliable rubber, you can manipulate it, roll the rubber around, so as to set the hoop-horizon for any place at any time!

Any latitude, any date of the year, any time of the night.

Even any precessional epoch of the remote past or future, though you would have to imagine the line of the equator, which is the join-seam of the globe’s halves, in its precessionally shifted places.  You could use the hoop-rim to represent, instead of the horizon, the equator of another precessional epoch, so as to visualize the skies of remote ages.

The ecliptic is marked, with the dates where the Sun is on Jan. 1, 5, 10, and so on, which helps in setting the positions if you know how.

In my photos, the globe is set, on the outside for a mid-northern latitude and for the sidereal time when Orion is rising.

The device is really a planisphere, but a three-dimensional one, more ingenious, more complete – more flexible, in a word! – than the traditional planisphere.  Bruce had yet to solve the technical problem of the mass printing of the celestial map onto the flexible sphere.

I found Bruce and his girlfriend a place to sleep in my friend Judy’s house.

This was in the spring when Comet West (C/1975 V1) had come up from the south.  It came only two years after Comet Kohoutek, whose early exaggeration by the media had caused the public to be disappointed, so now the media paid no attention and most of the public missed what could have been the sky-spectacle of their lives – a comet that some call the most beautiful of the twentieth century.

I camped out in a meadow where I had a vegetable garden, behind the Furman campus.  I woke in the pre-dawn to start looking eastward; the comet was in Pegasus.  The sky was cloudless – except, damn it, for one wisp of cloud above the outline of Paris Mountain, in exactly the place to hide the comet!

Then I realized that that wisp of cloud was not a wisp of cloud: it was the many-million-mile tail of the great comet!  The comet’s body was still below the horizon.

Comet West C/1975 V1 rising over Paris Mountain

I hoped that Bruce, Jessica, and Judy would get up and come out in time to see it before the dawn brightened.  They did; I was still lying gazing at it when their gray forms came uncertainly stepping through the damp weeds behind me.

Bruce sought a commercial name for his rubber plani-hemi-sphere.  I already called it Star Hat.  But he named it nothing more original than Night Star.  He set up his Night Star Company at Santa Cruz in California.

He diversified a bit, selling other astronomical goods, and after a few years he told me it was time for a change, and went back to New Zealand, leaving his business, which had moved to Ashland, Oregon, to one of his associates, Richard Moeschl.

Exactly thirty years after Comet West, a column by E.C. Krupp in Sky & Telescope, 2006 March, on Omar Khayyâm’s “Bowl of Night,” mentioned “the Nightstar Company’s vinyl star globes… available in the late 1980s,” with a small photo that didn’t make clear the three-dimensional nature.


4 thoughts on “Devices, 1: Star Hat”

  1. All of the above evokes good memories: Kahoutek, West and Hayakutake were all successes for me. I still have the Night Star “Elephant’s Diaphragm” too, but the inner ring is no longer the correct, circumference, size – so that it rumples up inside. Oh well. I had the pleasure of giving navigational planetarium programs in the 1980s with a 1959 Spitz SC2 projector. Now there was a nice celestial sphere – of course the best view was from the projector itself – when on a ladder setting the planets for the day…
    – oh, and I’m staring at the edge of a Planetica orrery as I write this. Birds of a feather and all.
    btw, have never yet had a smartphone, app, or GPS though.
    Thanks for your rambles.

  2. Thanks for the interesting note about Bruce King’s novel device. I bought one of these, and while it could be tricky to operate (as Larry also noted). With practice, I got the hang of it and found a good tool – not only for immediate observations, but also for planning ahead. For my naked eye observations, rough approximation was plenty good enough. For more precision I would use the Rude Star Finder, but that rarely came into play. Also as Larry notes, the apps in modern mobile phones can be quite handy, but simply do not provide the tangible pleasure of working with manual devices, such as King’s ‘hat’, or planispheres, or astrolabes. Also fun to hear of your early involvement with King. Your reflection on Comet West reminded me of my observations of Hyakutake in 1996 – between humidity, clouds and lights, the terrible viewing conditions in Maryland left me quite frustrated. A family trip to the Sonoran desert perked up my spirits, but more than a week past peak, I figured it would not be impressive. With two toddler children, I had to set camp at nightfall, and couldn’t stop to even take a glimpse at the sky until gear was set and dinner cooked. Once done, I took a deep breath and looked up – nearly knocked over by the quality of viewing in that dry, still desert air with no lights at all. The shock and joy of the viewing was something I will never forget.

  3. I still have mine! Sits next to the Planetica Orrery on my desk. Too bad they are no longer available…

  4. Guy,

    Thanks for the post on the Night Star Company’s product. I remember it well and know that I sold a number of them through my own astronomy materials company (Celestial Products).

    It certainly was a “sexy” product in being novel in feel and operation. Many were bought most likely as gifts, on that basis. I believe it failed to catch on as a utilitarian device due to the fact that it required unattached (losable) accessories to set latitude and date/time input to match one’s observing location. It was difficult to manipulate a rotation of the sky to a new date/time without disturbing the latitude setting (a slipping of flexible vinyl sky over the horizon ring).

    Given the planetarium apps we can now put on portable devices and direct to the point of the sky we want to examine (in a choice of wavelength, no less) we have attained a new, different solution to the observer’s need to have a map of the sky narrow the view to just what is in the sky at a particular moment. Still, I love my simple planisphere with a grommet in the Celestial North Pole. Perhaps it is that my hand powers the rotation of sky in such a smooth, controlled manner and that at a glance I can see what time and date the sky will be positioned exactly there.


Leave a Reply to wtreyn Cancel reply