ASTRO(7) ASTRO(7)
NAME
astro - print astronomical information
SYNOPSIS
astro [ -dlepsatokm ] [ -cn ]
DESCRIPTION
Astro reports upcoming celestial events, by default for 24
hours starting now. The options are:
d Read the starting date. A prompt gives the input for-
mat.
l Read the north latitude, west longitude, and elevation
of the observation point. A prompt gives the input
format. If l is missing, the initial position is read
from the file /lib/sky/here.
c Report for n (default 1) successive days.
e Report fractional overlap during eclipses.
p Print the positions of objects at the given time rather
than searching for interesting conjunctions. For each,
the name is followed by the right ascension (hours,
minutes, seconds), declination (degrees, minutes, sec-
onds), azimuth (degrees), elevation (degrees), and
semidiameter (arc minutes). For the sun and moon, the
magnitude is also printed.
s Print output in English words suitable for speech syn-
thesizers.
a Include a list of artificial earth satellites for
interesting events. (There are no orbital elements for
the satellites, so this option is not usable.)
t Read ΔT from standard input. ΔT is the difference
between ephemeris and universal time (seconds) due to
the slowing of the earth's rotation. ΔT is normally
calculated from an empirical formula. This option is
needed only for very accurate timing of occultations,
eclipses, etc.
o Search for stellar occultations.
k Print times in local time (`kitchen clock') as
described in the timezone environment variable.
m Includes a single comet in the list of objects. This
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ASTRO(7) ASTRO(7)
is modified (in the source) to refer to an approaching
comet but in steady state usually refers to the last
interesting comet (currently Levy, 1990c).
FILES
/lib/sky/estartab ecliptic star data
/lib/sky/here default latitude (N), longitude (W), and
elevation (meters)
SOURCE
/sys/src/cmd/astro
SEE ALSO
scat(7)
BUGS
The k option reverts to GMT outside of 1970-2036.
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