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Efemerydy zakryć asteroidalnych – E. Goffin

Efemerydy zawierają zakrycia asteroidalne gwiazd do 12,5 mag. W przypadku zakryc przez obiekty TNO gwiazdy do 15 mag.


Explanation of the graphs

• The top line gives the name of the major or minor planet and the star designation. The latter is only used to identify the star.

• The second line gives the instant of closest geocentric approach (in U.T.).

• Under the heading ”Planet” the following data are given: – a = semi-major axis, e = eccentricity of the orbit – V. mag. = visual magnitude of the planet – Diam. = absolute diameter in km and apparent diameter in seconds of arc. – µ = instantaneous motion at closest approach, in seconds of arc per hour. – π = horizontal equatorial parallax in seconds of arc. – Ref. = source for the orbital elements.

• Under the heading ”Star” are given: – Source cat. = an abbreviation for the source catalogue from which the positional data for the star are taken: ∗ FK6 = FK6 Catalogue (Parts I and III) ∗ HIP-2 = Hipparcos catalogue ∗ TYC2 = Tycho-2 catalogue; the suffix ”p” indicates Tycho data referring to the photocentre of two entries ∗ UCAC4 = Fourth USNO CCD Astrograph Catalog ∗ PPMX = PPMX catalogue – α = right ascension (J2000.0) at the epoch of occultation – δ = declination (J2000.0) at the epoch of occultation – V/Rmag = visual magnitude of the star if given, else the red magnitude if given, else blank – B/Imag = blue magnitude of the star if given, else the infrared magnitude if given, else blank

• The last line contains information about the occultation: 2 – ∆m = drop in magnitude – Max. dur. = maximum duration for an observer on the central line (in seconds of time) – Sun = elongation of the Sun (in degrees) – Moon = elongation (in degrees) and illuminated fraction (in %) of the Moon • The small star chart shows a portion of the sky of about 15 by 15◦ . Only stars of visual magnitude 7.0 and brighter are included. The dashed rectangle indicates the part shown by the larger chart.

• The large star chart is based on the merged catalogue or on both catalogues. The star to be occulted is encircled and is always in the middle. A visual-magnitude scale is added to the right, mostly ranging from 1 to 10; for faint stars the range may be 2–11, 3–12, etc. The star chart also shows the path of the minor planet with crosses indicating the daily position at 0h UT.

• The world map shows the Earth as seen from the star, i.e. the centre of the disk is the point on the Earth’s surface where the star is in the zenith. The night side is the part within the heavy lines. The shadow path is indicated by the central line and the northern and southern limits (including the effect of the Earth’s rotation). The dashed lines show the position of the central line for a shift of 100 perpendicular to the predicted shadow path (i.e. for a difference of ±1 00 in the shortest geocentric distance planet-star) . The times written at the bottom refer to the first and last cross lines; also the interval between two cross lines is given