Transit of Venus
2012 Jun 06
Local Circumstances
World visibility map (clickable)
General Information
Transiting Planet = Venus
Greatest Transit = 2012 Jun 06 01:30:43 TT
Gr. Longitude = 157° 13.6' E
Gr. Latitude = 22° 49.4' N
Transit Series = 7
Series Member = 7 of 47
Local Circumstances
Longitude = 25° 20' 00" E
Latitude = 42° 12' 00" N
Elevation = 169m.
Temperature = 10°C
Pressure = 1010 hPA
ΔT = 67.75s
Calendar Date and Time Azi Alt PA Sep S.D.
Rise 2012-Jun-06 02:43:34.2 57.8° 0.0° 317.3° 606.2" 29.4"
Contact III 2012-Jun-06 04:37:40.7 75.9° 18.9° 291.4° 916.3" 29.4"
Contact IV 2012-Jun-06 04:55:24.6 78.6° 22.1° 289.0° 975.1" 29.4"
Explaination of prediction
Greatest Transit The instant of minimum geocentric angular separation between centers of Venus and Sun,
in Terrestrial Time.
Gr. Longitude/Latitude WGS 84 coordinates of location at which Venus is directly overhead at Greatest Transit.
Transit Series Transits of Venus, separated by roughly 243 years are said to form transit series.
All transits that belong to one such series occur near either planet's ascending or
descending node.
Series Member Number of consecutive transit from the specified transit series.
Longitude/Latitude The observer's WGS 84 geographical coordinates. Default: Chirpan, Bulgaria.
Elevation Elevation of observer with respect to the WGS 84 oblate spheroid, in meters.
Temperature/Pressure Atmospheric conditions at observer's location. Affect rise/set times and apparent
altitudes of Sun and Venus. Default: 10° C & 1010 hPA.
ΔT The estimated arithmetic difference between Terrestrial Time and Universal Time.
Calendar Date and Time Calendar Date and Time of specific event, in Gregorian calendar and Universal Time,
assuming specified value of ΔT.
Contact I Apparent discs of Venus and Sun are externally tangent, a.k.a exterior ingress.
Contact II Apparent discs of Venus and Sun are internally tangent, a.k.a interior ingress.
Contact III Apparent discs of Venus and Sun are internally tangent, a.k.a interior egress.
Contact IV Apparent discs of Venus and Sun are externally tangent, a.k.a exterior egress.
Rise/Set If transit is in progress at rise or set, estimated times of rise or set are
displayed. Affected by Temperature and Pressure settings.
Azi Planetary Azimuth at specified time (0 = North; 90 = East; 180 = South; 270 = West).
Alt Planetary Altitude at specified time, including refraction (0 = horizon; 90 = zenith).
PA Position angle of Venus's center with respect to the center of Sun (0 = North;
90 = East; 180 = South; 270 = West).
Sep Separation between centers of Sun and Venus, in arcseconds.
S.D. Apparent angular semi-diameter of Venus, in arcseconds.
Duration Time interval between transit's first and fourth contacts.
About Predictions
Local Circumstances Generator makes use of JPL DE421 ephemerides and numerical integration software SOLEX. Geocentric positions of Sun and Venus through one minute intervals were generated, which were then converted to topocentric. Local circumstances were then computed on the assumption of linear motion during these intervals, which should be accurate enough for most purposes. Rise and set times are typically accurate to about a minute, due to impossibility to predict exact atmospheric refraction. Rise and set times are computed for the instant at which center of planetary disc would be at apparent horizon, using Saemundsson's formula for computing refraction near horizon. By default, air temperature of 10 degrees celsius and atmospheric pressure of 1010 hectopascals are assumed. These can be changed over a certain range in order to get more accurate times and see what effect could temperature and air pressure have on apparent positions.
Planetary transits catalogs