Transit of Venus from Jupiter

A transit of Venus across the Sun as seen from Jupiter takes place when the planet Venus passes directly between the Sun and Jupiter, obscuring a small part of the Sun's disc for an observer on Jupiter. During a transit, Venus can be seen from Jupiter as a small black disc moving across the face of the Sun.

Naturally, no one has ever seen a transit of Venus from Jupiter, nor is this likely to happen in the foreseeable future. Nevertheless, the next one will take place on September 20 2012.

A transit could hypothetically be observed from the surface of one of Jupiter's moons rather than from Jupiter itself. The times and circumstances of the transits would naturally be slightly different.

The Venus-Jupiter synodic period is 236.992 days. It can be calculated using the formula 1/(1/P-1/Q), where P is the sidereal orbital period of Venus (224.695434 days) and Q is the orbital period of Jupiter (4330.595 days).

The inclination of Venus's orbit with respect to Jupiter's ecliptic is 2.26°, which is less than its value of 3.39° with respect to Earth's ecliptic.

Since Jupiter has a very large radius, the parallax of Venus between Jupiter's center and its north or south pole would be about 22", which is about 6 times Venus's apparent angular diameter of 3.6", or about 5.6% of the Sun's angular diameter (about 6.5'). Therefore, some extremely close near-misses might be seen as grazing transits at Jupiter's poles.

ee also

* Astronomical transit

References

* Albert Marth, "Note on the Transit of the Planet Mars and its Satellites across the Sun’s disc, which will occur for the Planet Jupiter and its Satellites on April 13, 1886", Monthly Notices of the Royal Astronomical Society, 46 (1886), 161–164. [http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1886MNRAS..46..161M]