The Lubbock Thirty Degrees a Second Bench: The Sky and the Arc

THE LUBBOCK THIRTY DEGREES A SECOND BENCH · D154 pp. 6 to 9 × RUPPELT 1956 CH. 8
A formation of lights timed across the sky from a backyard: the one measurement, and every height it allows
a rate across the sky is a speed over a height, so the height is a dial and every speed follows
the professors' 30 degrees per second is measured; the record's heights and speeds are readings of it
the geometry, the magnitudes and the camera are exact; the height, the speed, the formation and the duck are dials
the sources measured no height, no speed and no size; the speaker's 75 to 80 feet is his own arithmetic, printed beside the bench's
watch the pass · read the arc · price the light · load the camera · open the file

Evidence

fact ⇄ what kind of claim · live

The speaker (D154): five professors, the backyard, the stopwatch, the baseline that failed, 12 objects over five or six nights; Hart's Kodak 35 at 1/10 s and f/3.5 on Plus-X, tracked; the office's density test, 'a little bit more than that of a bright planet'; ducks at 60 miles an hour 'about 75 to 80 feet'; 'they say they are not ducks'. Ruppelt 1956: 45° above the north horizon to 45° above the south, 90° in 3 s; Hart's 120° in 4 s; 10,000 feet and 3,600 mph; no stars on the negatives; plover; the mercury-vapour streets; his closing

the record's and the book's own words, with page and chapter; nothing added

REPORTED

30 degrees per second across the sky, the professors' measurement with a stopwatch and the angles of their houses

D154 p. 7: 'the only measurement we've got on these things'; Ruppelt 1956: '90 degrees of sky in three seconds'

MEASURED

2.08 μlx from a star of magnitude 0; the planet magnitudes; the urban and dark naked-eye limits; the lux table; a candle's candela; Lubbock's latitude, longitude and height; the Yale Bright Star Catalogue; the USNO phases of the Moon; the Kodak 35's 50 mm f/3.5 lens on a 24 × 36 mm frame; the ISA sound speed

reference tables named on the File

TABULATED

ω = v/h overhead; the sweep and the time of a symmetric arc; the height each reading gives a speed; magnitudes from intensities and distances; the duck's candela from its area, albedo and the light under it; the frame, the smear and the crossing time; the stars' places by sidereal time

arithmetic on the record's figures and the tables; no constant fitted

EXACT

The height, the speed, the arc's end elevation, the formation's count, width and shape; the city's illuminance, the ground's and the bird's albedo and area; the shutter and the pan; the hour; the backyard, the houses and the boulevard

the sources give none of them; shown as dials and staging

MODELLED

What the lights were, and what the distance between the readings means

the question this bench leaves to you

READING

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